ALBERT

Description: 〈p〉Publication date: November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 235〈/p〉 〈p〉Author(s): Sanober Kahkashan, Xinhong Wang, Jianfang Chen, Youcheng Bai, Miaolei Ya, Yuling Wu, Yizhi Cai, Siquan Wang, Monawwar Saleem, Javed Aftab, Asif Inam〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Perfluoroalkyl substances (PFAS) and organochlorine pesticides (OCPs) in surface sediments were investigated from the Bering Sea, the Chukchi Sea and adjacent Arctic Ocean in 2010. Total concentrations (dry weight) of Σ〈sub〉14〈/sub〉PFAS in surface sediments (0.85 ± 0.22 ng g〈sup〉−1〈/sup〉) of the Bering Sea were lower than that in the Chukchi Sea and adjacent Arctic Ocean (1.27 ± 0.53 ng g〈sup〉−1〈/sup〉). Perfluoro-butanoic acid (PFBS) and perfluoro-octanoic acid (PFOA) were the dominant PFAS in these areas. The concentrations of Σ〈sub〉15〈/sub〉OCPs in the sediment of the Bering Sea (13.00 ± 6.17 ng g〈sup〉−1〈/sup〉) was slightly higher than that in the Chukchi and Arctic Ocean (12.05 ± 2.27 ng g〈sup〉−1〈/sup〉). The most abundant OCPs were hexachlorocyclohexane isomers (HCHs) and dichlorodiphenyltrichloroethane (DDT) and its metabolites. The composition patterns of HCHs and DDTs indicated that they were mainly derived from the early residues via river runoff. Increasing trends of PFAS, HCHs and DDTs in surface sediments from the Bering Sea to the Arctic Ocean were found, indicating oceanic transport. In summary, the concentrations of OCPs were orders of magnitude greater than the observed PFAS concentrations, and the concentrations of PFAS and OCPs in surface sediments from the Bering Sea to the Chukchi Sea and adjacent Arctic Ocean are at the low to moderate levels by comparing with other coastal and marine sediments worldwide.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 235〈/p〉 〈p〉Author(s): Misganaw Alemu Zeleke, Dong-Hau Kuo〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Methylene blue dye is among the toxic, mutagenic, and carcinogenic pollutants. Hence, its treatment via photocatalytic degradation is an important remediation method for the sake of a healthy environment. Herein, the V〈sub〉2〈/sub〉O〈sub〉5〈/sub〉-CeO〈sub〉2〈/sub〉 nanocomposite catalysts were synthesized via a simple precipitation-thermal decomposition approach and used for the photodegradation of methylene blue in the presence of H〈sub〉2〈/sub〉O〈sub〉2〈/sub〉 as an effective electron scavenger under visible light illumination. The nanocomposite catalysts were systematically characterized to investigate the effects of V〈sub〉2〈/sub〉O〈sub〉5〈/sub〉 with the aids of X-ray, morphology, light absorption, catalytic activity, and charge transfer properties of the nanocomposite catalysts. The VC-2 nanocomposite prepared with NH〈sub〉4〈/sub〉VO〈sub〉3〈/sub〉:CeO〈sub〉2〈/sub〉 molar ratios at 0.15:1 was found to be the best efficient catalyst where ≥98% of methylene blue was degraded within 25 min irradiation time. From the kinetics analysis, its rate constant was found to be higher than those of the pure V〈sub〉2〈/sub〉O〈sub〉5〈/sub〉 and CeO〈sub〉2〈/sub〉 catalysts by a factor of 12.0 and 13.5, respectively. The plausibly mechanistic elucidation of charge transfer and utilization of reactive species are conspicuous allegations of the combined effects of the nanocomposite catalyst, H〈sub〉2〈/sub〉O〈sub〉2〈/sub〉 sacrificial agent, and visible light for the photodegradation of the dye.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519314717-fx1.jpg" width="294" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 235〈/p〉 〈p〉Author(s): Noreen Khalid, Atifa Masood, Ali Noman, Muhammad Aqeel, Muhammad Qasim〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Various physiological and biochemical responses of two good biomonitor plant species i.e. 〈em〉Datura alba〈/em〉 and 〈em〉Ricinus communis〈/em〉 were studied along two roads in the Punjab, Pakistan. Chlorophyll 〈em〉a〈/em〉, 〈em〉b〈/em〉, total chlorophylls, carotenoids, total free amino acids, total soluble proteins, total antioxidant activity, stomatal conductance, photosynthetic rate, internal CO〈sub〉2〈/sub〉 concentration, transpiration rate, and water use efficiency of 〈em〉D. alba〈/em〉 and 〈em〉R. communis〈/em〉 were examined at different sites along both roads. Photosynthetic rate of both plant species was found to be affected. Reduced transpiration rate and stomatal conductance were also noted. However, elevated internal CO〈sub〉2〈/sub〉 concentration and water use efficiency were recorded. Total soluble proteins got reduced, but, we found a tremendous increase in total antioxidant activity and total free amino acids in both plant species. 〈em〉D. alba〈/em〉 was found to be more affected by the adverse effects of roadside air borne pollutants. Although 〈em〉R. communis〈/em〉 was also affected but it showed minimal variation in all parameters compared to the control. Hence, our results suggest that 〈em〉R. communis〈/em〉 is more resistant to urban roadside air pollution compared to 〈em〉D. alba〈/em〉 and would be a good choice as phytoremediator of traffic borne pollutants, whereas, 〈em〉D. alba〈/em〉 could be a better biomonitoring plant.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 235〈/p〉 〈p〉Author(s): Houjuan Xing, Muqiao Peng, Zhuo Li, Jianqing Chen, Hongfu Zhang, Xiaohua Teng〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Ammonia is a known environmental pollutant around the world. It leads to the deterioration of air quality and has adverse effects on human health. Although previous studies have demonstrated that ammonia caused some health problems to chickens, it is still unclear whether ammonia causes cardiac toxicity. The functional autophagy is very important for cardiac homeostasis. Therefore, the role of autophagy was investigated in the mechanism of chicken heart damage induced by environmental contaminant ammonia in our present study. The results from the oxidative stress index (SOD, GPx, H〈sub〉2〈/sub〉O〈sub〉2〈/sub〉, and MDA), NO content, iNOS activity, and transmission electron microscopy indicated that excess ammonia induced oxidative stress and autophagy in the chicken heart. The expression results from miR-202-5p and PTEN/AKT/mTOR (PTEN, LC3-I, LC3-II, p-AKT, AKT, Beclin1, Dynein, ATG5, p-mTOR and mTOR) signaling pathway-related genes further confirmed that excess ammonia induced cardiac autophagy. In conclusion, these results demonstrated that excess ammonia can cause cardiac damage and mediate mir-202-5p to regulate autophagy through PTEN/AKT/mTOR pathway in the chicken heart injury. Our findings will provide a new insight for better assessing the toxicity mechanism of environmental pollutants ammonia on the heart.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519314766-fx1.jpg" width="304" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: November 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 235〈/p〉 〈p〉Author(s): Can Chen, Xu Wang, Jianlong Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this paper, the growth of 〈em〉S. bicolor〈/em〉 in Cd-polluted sandy clay loam soil in north China, Cd accumulation in plant and the corresponding soil microbial community were characterized when the plant matured (140 d of growth). Cadmium promoted the growth of mature 〈em〉S. bicolor〈/em〉 with higher height and heavier dry mass, especially at the spiked level of 1 mg kg〈sup〉−1〈/sup〉 soil (P 〈 0.05). The higher microbial diversity was found under Cd stress at the spiked level of 15 mg kg〈sup〉−1〈/sup〉, which basically corresponded with its influence on the plant growth. High-throughput sequencing data demonstrated that the predominant bacterial phyla include 〈em〉Proteobacteria〈/em〉 (35.99% for Cd-polluted soil and 35.22% for the control soil), 〈em〉Chloroflexi〈/em〉 (21.33% and 20.58%), 〈em〉Actinobacteria〈/em〉 (12.00% and 12.89%), 〈em〉Acidobacteria〈/em〉 (7.47% and 11.14%), 〈em〉Bacteroidetes〈/em〉 (7.37% and 6.96%), 〈em〉Gemmatimonadetes〈/em〉 (5.60% and 6.65%), 〈em〉Firmicutes〈/em〉 (2.82% and 1.86%), 〈em〉Planctomycetes〈/em〉 (2.47% and 0.95%), 〈em〉Saccharibacteria〈/em〉 (1.26% and 1.11%). The predominant fungal phyla was 〈em〉Ascomycota〈/em〉, with the relative abundance of 89.96% for the control soil and 86.2% for the Cd-polluted soil. 〈em〉S. bicolor〈/em〉 could grow well in sandy clay loam soil in northern China at low Cd lvel, but it could not accumulate cadmium at higher cadmium level. 〈em〉S. bicolor〈/em〉 could be used for phytoextraction of cadmium from the lightly Cd-polluted soil.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Liheng Liu, Dongwei He, Fei Pan, Rong Huang, Hua Lin, Xuehong Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this study, Fe/Cu, Fe/Al/Cu, Fe/Cu/C and Fe/Al/Cu/C internal electrolysis systems (IESs) were constructed and used to treat methylene blue dye (MB) wastewater. The effects of filler mass ratio, filler dosage, solution pH, reaction time and reaction temperature on COD removal were discussed, while the kinetics, thermodynamics and mechanism of COD removal were also investigated. The results showed that when the COD removal rates were basically the same, the reaction times of Fe/Al/Cu, Fe/Cu/C and Fe/Al/Cu/C IESs were shorter, and the filler dosages were lower. For the four systems, the appropriate pH was around 5, while the suitable reaction temperature was in the range of 20–25 °C. The COD removals of these four IESs were generally greater than 90%. The COD removal processes of the four systems could be better described by the improved pseudo-second-kinetic model, and the liquid film diffusion was the rate-controlling step. Moreover, the COD removal was a spontaneous and endothermic process. MB was degraded into inorganic substances in four steps. In addition, the FTIR characterization of the fillers before and after reaction suggests the four IESs have good stability.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Yong-Tao Li, Dan Li, Lian-Jue Lai, Yu-Hang Li〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This study investigates the degradation of petroleum hydrocarbon in contaminated soil using activated persulfate (PS) with ultrasound (US) and US/Fe. Various controlling factors including different PS dosage, ultrasonic power, pH, soil water ratio and soil particle size were considered. It was found that petroleum hydrocarbon degradation efficiency achieved up to 56.41% and 82.23% in US/PS and US/Fe/PS system, respectively. Based on the experimental results, the reaction rate of US/Fe/PS system was faster than US/PS system and the degradation efficiency enhanced significantly with the increasing ultrasonic power. Changing initial solution pH influenced the petroleum hydrocarbon reaction rate and the best performance would be achieved at pH of 5. The present work identified the main components of petroleum hydrocarbon pollutants in shale gas sites. The mechanism of petroleum hydrocarbon degradation on US/Fe/PS system were analyzed.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Muhammad Adrees, Zahra Saeed Khan, Shafaqat Ali, Muhammad Hafeez, Sofia Khalid, Muhammad Zia ur Rehman, Afzal Hussain, Khalid Hussain, Shahzad Ali Shahid Chatha, Muhammad Rizwan〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Excess amount of cadmium (Cd) in arable soils and shortage of good quality water are the major abiotic factors affecting the crop yield which needs immediate solution to feed the increasing population worldwide. Recently, nanoparticles (NPs) are widely used in various industries including agriculture which is due to the unique properties of NPs. Among NPs, iron (Fe) NPs might be used to alleviate the abiotic stresses in crops but limited informations are available in the literature about the role of Fe-NPs in crops under metal stress. The present study was designed to highlight the efficiency of Fe-NPs on Cd accumulation in Cd and drought-stressed wheat. Wheat plants were grown in Cd-contaminated soil after the supply of different levels of Fe-NPs and two water regimes were introduced in the soil in latter growth stages of the plants. Cadmium and drought stress negatively affected the wheat photosynthesis, yield and caused oxidative stress in leaves with excess accumulation of Cd in grains and other plant tissues. The NPs improved the photosynthesis, yield, Fe concentrations and diminished the Cd concentrations in tissues. The NPs alleviated the oxidative stress in leaves and the efficiency depends on the NPs concentrations applied in the soil. The results obtained indicated that Fe-NPs may be employed aiming to get wheat grains with excess Fe and decreased Cd contents. However, field investigations with various sizes, shapes and levels of NPs are needed before final recommendations to the farmers.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Hidehiro Ishizawa, Yuka Ogata, Yoshiyuki Hachiya, Ko-ichiro Tokura, Masashi Kuroda, Daisuke Inoue, Tadashi Toyama, Yasuhiro Tanaka, Kazuhiro Mori, Masaaki Morikawa, Michihiko Ike〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Plant growth-promoting bacteria (PGPB) are considered a promising tool to improve biomass production and water remediation by the aquatic plant, duckweed; however, no effective methodology is available to utilize PGPB in large hydroponic systems. In this study, we proposed a two-step cultivation process, which comprised of a “colonization step” and a “mass cultivation step,” and examined its efficacy in both bucket-scale and flask-scale cultivation experiments. We showed that in the outdoor bucket-scale experiments using three kinds of environmental water, plants cultured through the two-step cultivation method with the PGPB strain, 〈em〉Acinetobacter calcoaceticus〈/em〉 P23, yielded 1.9 to 2.3 times more biomass than the control (without PGPB inoculation). The greater nitrogen and phosphorus removals compared to control were also attained, indicating that this strategy is useful for accelerating nutrient removal by duckweed. Flask-scale experiments using non-sterile pond water revealed that inoculation of strain P23 altered duckweed surface microbial community structures, and the beneficial effects of the inoculated strain P23 could last for 5–10 d. The loss of the duckweed growth-promoting effect was noticeable when the colonization of strain P23 decreased in the plant. These observations suggest that the stable colonization of the plant with PGPB is the key for maintaining the accelerated duckweed growth and nutrient removal in this cultivation method. Overall, our results suggest the possibility of an improved duckweed production using a two-step cultivation process with PGPB.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Isaac Sánchez-Montes, José F. Pérez, Cristina Sáez, Manuel A. Rodrigo, Pablo Cañizares, José M. Aquino〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Significance of surface and ground water contamination by synthetic organic compounds has been pointed out in a very high number of papers worldwide, as well as the need of application of treatment technologies capable to assure their complete removal. Among these processes, the electrochemical advanced oxidation is an interesting option, especially when irradiated with UVC light (photo-electrochemical, P-EC) to promote homolysis of electrogenerated oxidants. In this work, the herbicide glyphosate (GLP) was used as model compound and it was electrochemically treated under UVC irradiation in the presence of NaCl and using a DSA® and BDD anodes. Total organic carbon concentration was measured throughout the electrolysis, as well as the concentration of short chain carboxylic acids and inorganic ions (NO〈sub〉3〈/sub〉〈sup〉−〈/sup〉, PO〈sub〉4〈/sub〉〈sup〉3−〈/sup〉,ClO〈sup〉−〈/sup〉, ClO〈sub〉3〈/sub〉〈sup〉−〈/sup〉 and ClO〈sub〉4〈/sub〉〈sup〉−〈/sup〉). The synergism of the P-EC was more pronounced when using a DSA® electrode, which led to complete GLP mineralization in 1 h (0.52 A h L〈sup〉−1〈/sup〉), as also confirmed by the stoichiometric formation of NO〈sub〉3〈/sub〉〈sup〉−〈/sup〉 and PO〈sub〉4〈/sub〉〈sup〉3−〈/sup〉 ions, with an energy consumption as low as 1.25 kW h g〈sup〉−1〈/sup〉. Unexpectedly, the concentration evolution of oxyhalides for the P-EC process using both anodes, especially for DSA® at 10 mA cm〈sup〉−2〈/sup〉, showed the production of ClO〈sub〉3〈/sub〉〈sup〉−〈/sup〉, whereas detection of ClO〈sub〉4〈/sub〉〈sup〉−〈/sup〉 species was only found when using BDD at 100 mA cm〈sup〉−2〈/sup〉 for the electrochemical process. Finally, small amounts of carboxylic acids were detected, including dichloroacetic acid, especially when using a BDD electrode.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Zhao Jiang, Jianing Chen, Jiaojiao Li, Bo Cao, Yukun Chen, Di Liu, Xinxin Wang, Ying Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Enhancing the biodegradation efficiency of atrazine, a kind of commonly applied herbicide, has been attracted much more concern. Here, Zn〈sup〉2+〈/sup〉 which has long been considered essential in adjusting cell physiological status was selected to investigate its role on the biodegradation of atrazine by 〈em〉Arthrobacter〈/em〉 sp. DNS10 as well as the transmembrane transport of atrazine during the biodegradation period. The results of gas chromatography showed that the atrazine removal percentages (initial concentration was 100 mg L〈sup〉−1〈/sup〉) in 0.05 mM Zn〈sup〉2+〈/sup〉 and 1.0 mM Zn〈sup〉2+〈/sup〉 treatments were 94.42% and 86.02% respectively at 48 h, while there was also 66.43% of atrazine left in the treatment without exogenous Zn〈sup〉2+〈/sup〉 existence. The expression of atrazine chlorohydrolase gene 〈em〉trz〈/em〉N in the strain DNS10 cultured with 0.05 mM and 1.0 mM Zn〈sup〉2+〈/sup〉 was 7.30- and 4.67- times respectively compared with that of the non-zinc treatment. In addition, the flow cytometry test suggests that 0.05 mM of Zn〈sup〉2+〈/sup〉 could better adjust the membrane permeability of strain DNS10, meanwhile, the amount of atrazine accumulation in the strain DNS10 co-cultured with this level Zn〈sup〉2+〈/sup〉 was 2.21 times of that of the strain without Zn〈sup〉2+〈/sup〉. This study may facilitate a better understanding of the mechanisms that exogenous Zn〈sup〉2+〈/sup〉 enhances the biodegradation of atrazine by 〈em〉Arthrobacter〈/em〉 sp. DNS10.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519318181-egi10JM2SCGSQ7.jpg" width="281" alt="Image 1027" title="Image 1027"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Daisuke Inoue, Tsubasa Tsunoda, Kazuko Sawada, Norifumi Yamamoto, Kazunari Sei, Michihiko Ike〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This study evaluates the effects of various metals on 1,4-dioxane degradation by the following four bacteria: 〈em〉Pseudonocardia〈/em〉 sp. D17; 〈em〉Pseudonocardia〈/em〉 sp. N23; 〈em〉Mycobacterium〈/em〉 sp. D6; and 〈em〉Rhodococcus aetherivorans〈/em〉 JCM 14343. Eight transition metals [Co(II), Cu(II), Fe(II), Fe(III), Mn(II), Mo(VI), Ni(II), and Zn(II)] were used as the test metals. Results revealed, for the first time, that metals had not only inhibitory but also stimulatory effects on 1,4-dioxane biodegradation. Cu(II) had the most severe inhibitory effects on 1,4-dioxane degradation by all of the test strains, with significant inhibition at concentrations as low as 0.01–0.1 mg/L. This inhibition was probably caused by cellular toxicity at higher concentrations, and by inhibition of degradative enzymes at lower concentrations. In contrast, Fe(III) enhanced 1,4-dioxane degradation by 〈em〉Mycobacterium〈/em〉 sp. D6 and 〈em〉R. aetherivorans〈/em〉 JCM 14343 the most, while degradation by the two 〈em〉Pseudonocardia〈/em〉 strains was stimulated most notably in the presence of Mn(II), even at concentrations as low as 0.001 mg/L. Enhanced degradation is likely caused by the stimulation of soluble di-iron monooxygenases (SDIMOs) involved in the initial oxidation of 1,4-dioxane. Differences in the stimulatory effects of the tested metals were likely associated with the particular SDIMO types in the test strains.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 22 August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere〈/p〉 〈p〉Author(s): Yunfeng Ma, Xiaoqing Lin, Zhiliang Chen, Xiaodong Li, Shengyong Lu, Jianhua Yan〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Studies are carried out in two wet scrubbing systems (WSSs) subordinated to two similar full-scale (30 t h〈sup〉−1〈/sup〉) municipal solid waste (MSW) incinerators to explore the influence factors and mass balance of memory effect on polychlorinated-ρ-dibenzodioxins and dibenzofurans (PCDD/Fs) emissions. The results show that the memory effect on two WSSs notably increases the TEQ concentrations by 13.6 and 3 times, respectively, through increase in the total mass concentration and the proportions of low-chlorinated PCDD/Fs, directly resulting in the PCDD/F emissions of 1# MSW incinerator over the national standard. PCDD/F adsorption/desorption in WSSs is the reasonable acting mechanisms of memory effect. In addition, memory effect mainly influences gaseous PCDD/F emissions by elevating the percentage of PCDFs, while slightly affects PCDD/Fs in residuals. A mass balance of PCDD/Fs is established to further analyze the influence factors of memory effect on WSSs, indicating filling as the largest potential source discharging PCDD/Fs into outlet flue gas. The results pave the way for further industrial optimization of WSSs design, such as the filling materials with less adsorption capacity on PCDD/Fs and more reasonable operation.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: Available online 22 August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere〈/p〉 〈p〉Author(s): Hana Stiborova, Michal Strejcek, Lucie Musilova, Katerina Demnerova, Ondrej Uhlik〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉Despite wastewater treatment, sewage sludge is often contaminated with multiple pollutants. Their impact on the phylogenetic composition and diversity of prokaryotic communities in sludge samples remains largely unknown. In this study, we analyzed the phylogenetic structure of bacterial communities and diversity in sludge from six waste water treatment plants (WWTPs) and linked this information with the pollutants identified in these samples: eight potentially toxic metals (PTMs) and four groups of organic pollutants [polychlorinated biphenyls (PCBs), polyromantic hydrocarbons (PAHs), brominated flame retardants (BFRs) and organic halogenated compounds (OCPs)].〈/p〉 〈p〉Alpha diversity measures and the distribution of dominant phyla varied among the samples, with the community from the thermophilic anaerobic digestion (TAD)-stabilized sample from Prague being the least rich and the least diverse and containing on average 36% of 16S rRNA gene sequence reads of the thermotolerant genus 〈em〉Coprothermobacter〈/em〉 of the class Clostridia (phylum Firmicutes). Using weighted UniFrac distance-based redundancy analysis (dbRDA), we found that a collection of 5 PTMs: Cr, Cu, Ni, Pb, Zn, and a pair of BFRs: hexabromocyclododecane (HBCD) and tribromodiphenyl ethers (triBDEs) were significantly associated with the bacterial community structure in mesophilic anaerobic digestion (MAD)-stabilized samples, whereas PCBs were observed to be marginally significant. Altogether, 85% of the variance in bacterial community structure could be ascribed to these pollutants. The data presented here contribute to a greater understanding of the ecological effects of combined pollution on the composition and diversity of bacterial communities, hence have the potential to aid in predicting ecosystem functions and/or disruptions associated with pollution.〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Sang-Ho Lee, Yoshio Takahashi〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The present study provides the starch-mediated carbothermal preparation of magnetic-responsible ferrihydrite (MFHP) based on Fe-rich precipitates which is recovered by mine drainage for immobilization of arsenate and antimonate in water. Fe K-edge X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) represented partial transformation from ferrihydrite to magnetite in MFHP due to the carbothermal reduction process, resulting in an effective saturation magnetism (= 19.2 emu/g). As and Sb K-edge EXAFS revealed that arsenate ion combines onto the surface of MFHP as inner-sphere binuclear bidentate surface complex, and antimonate forms inner-sphere mononuclear bidentate complex. In addition, the leachability by toxicity characteristic leaching procedure (TCLP) implies the environmental friendly preparation method for preparing magnetic-responsible adsorbents using mining waste.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519317138-fx1.jpg" width="499" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Masao Togao, Shouta M.M. Nakayama, Yoshinori Ikenaka, Hazuki Mizukawa, Yoshiki Makino, Ayano Kubota, Takehisa Matsukawa, Kazuhito Yokoyama, Takafumi Hirata, Mayumi Ishizuka〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Lead (Pb) pollution is one of the most serious environmental problems and has attracted worldwide attention. Pb causes hematological, central nervous system, as well as renal toxicity, and so on. Although many investigations about Pb in blood to evaluate pollution status and toxic effects have been reported, there are open question about biological behavior of Pb. In order to reveal any toxicological mechanisms or influences, we focused on the local distribution of Pb in mice organs. Lead acetate (100 mg/L and 1000 mg/L) in drinking water were given to the BALB/c mice (male, seven weeks of age, N = 24) for three weeks. Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) analysis revealed a homogenous distribution of Pb in the liver and inhomogeneous distribution in the kidney and brain. The hippocampus, thalamus, and hypothalamus had higher concentrations than other areas such as the white matter. Surprisingly, in the kidney, Pb tended to accumulate in the medulla rather than the cortex, strongly suggesting that high sensitivity areas and high accumulation areas differ. Moreover, distribution of stromal interacting protein 1 (STIM1) which is candidate gene of Pb pathway to the cells was homogenous in the liver and kidney whereas inhomogeneous in the brain. In contrast to our hypothesis, interestingly, Pb exposure under the current condition did not induce mRNA expressions for any candidate channel or transporter genes. Thus, further study should be conducted to elucidate the local distribution of Pb and other toxic metals, and pathway that Pb takes to the cells.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519318053-fx1.jpg" width="293" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): P. Finkbeiner, G. Moore, R. Pereira, B. Jefferson, P. Jarvis〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Three different source waters were investigated using virgin and pre-used anion exchange resins, coagulation, and ion exchange combined with coagulation (IEX&Coagulation). The hydrophobicity, size distribution and charge of natural organic matter (NOM) were used to evaluate its removal. Dissolved organic carbon (DOC) removal by pre-used IEX resin was 67–79%. A consistent ratio of different hydrophobicity fractions was found in the removed DOC, while the proportion and quantity of the molecular weight fraction around 1 kDa was important in understanding the treatability of water. For pre-used resin, organic compounds were hypothesised to be restricted to easily accessible exchange sites. Comparatively, virgin resin achieved higher DOC removals (86–89%) as resin fouling was absent. Charge density and the proportion of the hydrophobic fraction were found to be important indicators for the specific disinfection byproduct formation potential (DBP-FP). Treatment of raw water with pre-used resin decreased the specific DBP-FP by between 2 and 43%, while the use of virgin resin resulted in a reduction of between 31 and 63%. The highest water quality was achieved when the combination of IEX and coagulation was used, reducing DOC and the specific DBP-FP well below that seen for either process alone.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519318570-fx1.jpg" width="500" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Nathalie Lécrivain, Antoine Duparc, Bernard Clément, Emmanuel Naffrechoux, Victor Frossard〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Point pollution sources may differently impact lakes littoral, possibly leading to local ecological risks. The concomitant chemical analysis of littoral-benthic organisms and sediment can provide insights into the bioavailability and thus the ecological risk of contaminants. In this study, the autochthonous Corbicula fluminea was used to assess the sources and transfer of six trace metals (TMs) and fourteen Polycyclic Aromatic Hydrocarbons (PAHs) to the littoral-benthic biota of a large lake. The contaminant concentrations spatially varied with a value scale from 1 to 280 000 times along the lake littoral in both the sediment and clams. Multiple linear regressions were performed to explain the spatial variability of 〈em〉Corbicula fluminea〈/em〉 contamination by considering both watershed and in-lake sources. The concentration of the sum of PAHs in clams was significantly correlated with sediment contamination, suggesting that PAHs contamination of the benthic biota mainly occur from the sediment. Most of the internal TM concentrations of clams were significantly correlated with stormwater drainage areas in the lake watershed, highlighting the importance of stormwater runoffs in the littoral biota contamination. The transfer of TMs and PAHs was assessed through the bioconcentration factor defined as the ratio of internal and sediment concentrations. As, Cd, Cu, Zn and light molecular weight PAHs were more bioconcentrated in 〈em〉C. fluminea〈/em〉 than Pb, Sn and heavy molecular weight PAHs, suggesting differences in their bioavailability. This study underlines the relevance of using autochthonous organisms as bioindicators of lake littoral biota contamination concomitantly with sediment matrices, and illustrates the challenge of tracking pollution sources in lakes.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Divina A. Navarro, Mélanie Kah, Dusan Losic, Rai S. Kookana, Mike J. McLaughlin〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Graphene-based nanomaterials (GNMs) have been touted as miracle materials due to their extraordinary properties that can benefit many industries, including in agriculture and for environmental remediation. While improvement in nutrient delivery and the ability to adsorb environmental contaminants have been demonstrated, what happens to GNMs in soil is a question that has not been addressed. The main aim of this study was to investigate their degradation in soil to have a better understanding of their environmental fate. Using radioisotope techniques, this study assessed the potential mineralisation and release of graphene oxide (GO), one of the most commonly used forms of graphene. Results revealed that the conversion of GO to carbon dioxide was negligible (〈2%) in microbially-active soils. GO remaining in soil was also not readily released by water extractions. The lack of mineralisation and release is indicative of GO's high (bio)degradation stability which is likely due to its limited availability resulting from its rapid homo/hetero-aggregation. Over-all, the results provide new and important information on the environmental fate of graphene nanomaterials applied to soils.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519317825-fx1.jpg" width="495" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Silvia Casabianca, Samuela Capellacci, Antonella Penna, Michela Cangiotti, Alberto Fattori, Ilaria Corsi, Maria Francesca Ottaviani, Riccardo Carloni〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Plastics are the most abundant marine debris globally dispersed in the oceans and its production is rising with documented negative impacts in marine ecosystems. However, the chemical-physical and biological interactions occurring between plastic and planktonic communities of different types of microorganisms are poorly understood. In these respects, it is of paramount importance to understand, on a molecular level on the surface, what happens to plastic fragments when dispersed in the ocean and directly interacting with phytoplankton assemblages. This study presents a computer-aided analysis of electron paramagnetic resonance (EPR) spectra of selected spin probes able to enter the phyoplanktonic cell interface and interact with the plastic surface. Two different marine phytoplankton species were analyzed, such as the diatom 〈em〉Skeletonema marinoi〈/em〉 and dinoflagellate 〈em〉Lingulodinium polyedrum〈/em〉, in absence and presence of polyethylene terephthalate (PET) fragments in synthetic seawater (ASPM), in order to 〈em〉in-situ〈/em〉 characterize the interactions occurring between the microalgal cells and plastic surfaces. The analysis was performed at increasing incubation times. The cellular growth and adhesion rates of microalgae in batch culture medium and on the plastic fragments were also evaluated. The data agreed with the EPR results, which showed a significant difference in terms of surface properties between the diatom and dinoflagellate species. Low-polar interactions of lipid aggregates with the plastic surface sites were mainly responsible for the cell-plastic adhesion by 〈em〉S. marinoi〈/em〉, which is exponentially growing on the plastic surface over the incubation time.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519317849-fx1.jpg" width="337" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: Available online 20 August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere〈/p〉 〈p〉Author(s): Junyuan Guo, Yuling Zhou〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This work investigated the improvement performances and mechanisms of waste activated sludge (WAS) dewaterability and the transformation behavior of heavy metals (HMs, including Cu, Zn, Pb, Cd and Cr) by jointly conditioning of Fe〈sup〉2+〈/sup〉-activated peroxymonosulfate (PMS) oxidation and rice straw biochar (RS-BC). Experimental results showed that at original WAS pH of 6.5, the joint conditioning was the most effective when PMS dosage was 0.6 mmol·(g-volatile solids (VS))〈sup〉−1〈/sup〉, Fe〈sup〉2+〈/sup〉/PMS molar ratio was 0.6 and RS-BC dosage was 120 mg·(g-VS)〈sup〉−1〈/sup〉. Under this condition, the lowest moisture content (MC) was 38.5% and the standardized-capillary suction time (SCST) was as high as 8.74. For the improvement mechanism, Fe〈sup〉2+〈/sup〉-activated PMS oxidation can significantly disintegrate the extracellular polymeric substances (EPS) composing WAS to release EPS-bound water, and the RS-BC was helpful to form porous structures to improve WAS compressibility, facilitating the subsequent dewatering. In addition, Fe〈sup〉2+〈/sup〉-activated PMS oxidation can obviously improve the solubilization and reduce the leaching toxicity of Cu, Zn, Pb, Cd and Cr, which was further enhanced by RS-BC. Therefore, the joint application of Fe〈sup〉2+〈/sup〉-activated PMS oxidation and RS-BC can be a feasible way to improve WAS dewaterability and reduce HMs risk during WAS dewatering.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519318521-fx1.jpg" width="438" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: Available online 19 August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere〈/p〉 〈p〉Author(s): Fuzhen Liu, Yin Xu, Baisong Zhang, Yalu Liu, Hui Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract:〈/h5〉 〈div〉〈p〉An eco-friendly material, activated carbon cloth (ACC) was used as the heterogeneous catalyst in activation of peroxydisulfate (PDS) for the efficient degradation of organic pollutant in water. Besides, the effects of several parameters in the ACC/PDS process including initial pH, PDS concentration, reaction temperature, stirring speed and co-existing anions were investigated. Under optimum conditions, almost complete removal (98.6%) of AO7 in 60 min and 67.4% of total organic carbon (TOC) removal within 180 min were obtained, accompanied by the remarkable destruction of azo band and naphthalene ring on AO7. The electron paramagnetic resonance and radical quenching experiments were carried out to identify the reactive radicals in the ACC/PDS process. Surface characteristic techniques such as XRD, BET, SEM, FTIR, XPS were applied to analysis the change of crystal structure, surface area, surface morphology, functional groups on the surface of fresh and spent ACC samples. Hydroxyl groups (C‒OH) and π-π transitions significantly affected the catalytic activity of ACC. The intermediate products of AO7 oxidation were identified by LC-MS and the corresponding degradation pathway was proposed.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519318351-fx1.jpg" width="365" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Carla Patrícia Silva, Cindy Oliveira, Ana Ribeiro, Nádia Osório, Marta Otero, Valdemar I. Esteves, Diana L.D. Lima〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉Among pharmaceuticals, the occurrence of antibiotics in the environment is a subject of special concern due to their environmental impact, namely the development of bacterial resistance. Sulfamethoxazole (SMX) is one of the most commonly used antibiotics and it is regularly found, not only in effluents from sewage treatment plants (STPs), but also in the aquatic environment. Photodegradation appears as an alternative process for the removal of this type of pollutants from contaminated waters. In order to be used for a remediation purpose, its evaluation under continuous flow mode is essential, as well as the determination of the final effluent antibacterial activity, which were assessed in this work.〈/p〉 〈p〉As compared with batch operation, the irradiation time needed for SMX elimination under continuous flow mode sharply decreased, which is very advantageous for the target application. Moreover, the interrelation between SMX removal, mineralization and antibacterial activity was evaluated before and during photodegradation in ultrapure water. Although mineralization was slower than SMX removal, bacterial activity increased after SMX photodegradation. Such increase was also verified in environmental water matrices. Thus, this study has proven that photodegradation is an efficient and sustainable process for both (i) the remediation of waters contaminated with antibiotics, and (ii) the minimization of the bacterial resistance.〈/p〉 〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519318375-fx1.jpg" width="500" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Mohammad Behzadi Tayemeh, Milad Esmailbeigi, Iman Shirdel, Hamid Salari Joo, Seyed Ali Johari, Ashkan Banan, Hossein Nourani, Hamed Mashhadi, Mohammad Javad Jami, Mona Tabarrok〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This study assesses and compares the influence of silver nanoparticles (AgNPs) and silver nitrate (AgNO〈sub〉3〈/sub〉) on the fatty acid composition, pigments, and growth indices of 〈em〉Chlorella vulgaris〈/em〉. Toxicity testing was carried at the estimated and/or above predicted environmental concentrations of AgNPs and AgNO〈sub〉3〈/sub〉. AgNO〈sub〉3〈/sub〉 treatments impaired the population growth of 〈em〉C〈/em〉. 〈em〉vulgaris〈/em〉 about 2–183 times more than the respective AgNPs ones. The pigments displayed a concentration-dependent decrease in response to both forms of silver; however, AgNO〈sub〉3〈/sub〉 displayed higher severity to the pigments than AgNPs. In exposure to 10 μg L〈sup〉−1〈/sup〉 AgNO〈sub〉3〈/sub〉, the contents of chlorophyll 〈em〉a〈/em〉, chlorophyll 〈em〉b〈/em〉, total chlorophyll, and carotenoid, respectively, demonstrated a reduction of about 5, 3, 4, and 4 times when compared with the same respective concentration of AgNPs. Total amounts of saturated (∑SFA), monounsaturated (∑MUFA), and polyunsaturated (∑PUFA) fatty acids as well as the ratio of unsaturated to saturated ones (Unsat./Sat.) displayed somewhat similar-concentration responses. ∑SFA exhibited a hormesis response, and ∑MUFA, ∑PUFA, and Unsat./Sat. did a decreasing trend with increasing concentration of AgNPs and AgNO〈sub〉3〈/sub〉. Myristoleic acid, nervonic acid, and eicosadienoic acid revealed the highest sensitivity. Pearson analysis illustrated the highest correlation among myristoleic acid, eicosenoic acid, and nervonic acid as well as among palmitic acid, stearic acid, palmitoleic acid, and oleic acid. Taken together, AgNPs and the released ions could disrupt physiological health state of microalgae through perturbation in the fatty acid composition (especially MUFAs and PUFAs) and other macromolecules. These types of bioperturbations could change the good health state of aquatic ecosystems.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519318004-fx1.jpg" width="246" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Ashour M. Ahmed, Fatma Mohamed, Abdallah M. Ashraf, Mohamed Shaban, Aftab Aslam Parwaz Khan, Abdullah M. Asiri〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Hydrogen production from water splitting by a photocatalytic process is one way that can be used to solve global problems related to energy depletion and environmental pollution. This work aims to design and characterize a novel photocatalyst nanohybrid carbon nanotubes@TiO〈sub〉2〈/sub〉 nanoribbons (CNTs@TNRs) for enhanced photoelectrochemical (PEC) water splitting in different electrolytes under visible light irradiance. Here, hydrothermal and chemical vapor deposition (HT-CVD) were combined to grow CNTs @ the nanopits of TNRs producing network of nanohybrid CNTs@TNRs. The structural, morphological, optical, and photocatylatic properties of the TNRs and CNTs@TNRs nanohybrid were characterized by different techniques. The crystallite size is increased from 14.86 nm for TNRs to 21.61 nm for CNTs@TNRs nanohybrid. The CNTs@TNRs nanohybrid has well-resolved nanopits on the surface of the TNRs with an average diameter of 10 nm. The absorption edge of CNTs@TNRs relative to TNRs was strongly shifted to the visible light region. The band gap values are 3.78 and 2.07 eV for TNRs and CNTs@TNRs, respectively. The TNRs and CNTs@TNRs were used for the photocatalytic water splitting under visible light irradiance in Na〈sub〉2〈/sub〉S〈sub〉2〈/sub〉O〈sub〉3〈/sub〉, HCl and KOH electrolytes of different concentrations. The calculated incident photon-to-current conversion efficiency (IPCE) was 97% at 510 nm. These values are higher than those previously reported for different photoelectrodes. The number of hydrogen moles was calculated to be 300 μmol h〈sup〉−1〈/sup〉 cm〈sup〉−2〈/sup〉. Therefore, our work demonstrates a feasible route for efficient PEC water splitting under sunlight irradiation utilizing the novel CNTs@TNRs photocatalyst.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Boyuan Zhu, Hao Cheng, Jianfeng Ma, Yong Kong, Sridhar Komarneni〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract:〈/h5〉 〈div〉〈p〉Novel ZnS–ZnFe〈sub〉2〈/sub〉O〈sub〉4〈/sub〉 composites were successfully synthesized via a simple and green hydrothermal route. X-ray diffraction (XRD) patterns of the synthesized composite proved the presence of both ZnS and ZnFe〈sub〉2〈/sub〉O〈sub〉4〈/sub〉. The other characteristics of the composites were further characterized in detail using Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), UV–vis diffuse reflectance spectroscopy (UV–vis DRS) and vibrating sample magnetometry (VSM). The performance of ZnS–ZnFe〈sub〉2〈/sub〉O〈sub〉4〈/sub〉 in the presence of persulfate (PS, K〈sub〉2〈/sub〉S〈sub〉2〈/sub〉O〈sub〉8〈/sub〉) as a co-catalyst was tested for degrading rhodamine B (RhB) under UV light illumination. ZnS–ZnFe〈sub〉2〈/sub〉O〈sub〉4〈/sub〉 composites could remove about 97.67% of RhB in 90 min, which was much higher removal than either ZnS or ZnFe〈sub〉2〈/sub〉O〈sub〉4〈/sub〉 alone. Moreover, the recovery of catalyst and its recycling performance were found to be good after testing three times. A feasible mechanism analysis of RhB degradation was validated by simple classical quenching experiments. The enhanced performance was attributed to the high-efficiency separation rate of photo induced electron-hole pairs and highly active free radicals of O〈sub〉2〈/sub〉〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/rad"〉〈sup〉−〈/sup〉, OH〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/rad"〉 and SO〈sub〉4〈/sub〉〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/rad"〉〈sup〉−〈/sup〉.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519317710-egi107D9V20FFZ.jpg" width="342" alt="Image 107920" title="Image 107920"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Jingjing Zhao, Yu Yang, Chen Li, Jing Liang, Li-an Hou〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This study evaluated the effects of co-existing cations (Na〈sup〉+〈/sup〉 or Ca〈sup〉2+〈/sup〉) on the lamellar structure of cross-linked graphene oxide (GO) layers and GO modified membrane performance in terms of their fouling behaviours and retention for single-model organic matter, namely, bull serum albumin (BSA), sodium alginate (SA), humic acid (HA) and tannic acid (TA). In the absence of co-existing cations, the GO layers mitigated membrane fouling for large molecules (SA, BSA, and HA) but led to severer pore blocking for small molecules (TA) compared with pristine membrane. Na〈sup〉+〈/sup〉 and Ca〈sup〉2+〈/sup〉 altered the performance impacts of the GO modified membrane due to different interactions with the cross-linked GO layers. Low concentrations of Na〈sup〉+〈/sup〉 (〈0.4 mM) enlarged interlayer spacing of the GO layers and caused a decrease in flux after physical cleaning, but the GO layers maintained the uniform lamellar structure. High concentrations of Na〈sup〉+〈/sup〉 (〉0.4 mM) promoted the aggregation of cross-linked GO layers through charge shielding and reduced the uniformity of lamellar structure, which weakened the antifouling performance for large molecules and promoted the passage of small molecules through the membrane. However, Ca〈sup〉2+〈/sup〉 complexed with GO sheets and reinforced the uniform lamellar structure of the GO layers, leading to a better antifouling performance for the filtration of large molecules than the pristine membrane but aggravated TA fouling.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519317680-fx1.jpg" width="308" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Yuk Hang Chan, Ka Hou Chu, King Ming Chan〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉To characterize the potential endocrine-disrupting chemicals (EDCs) in the environment that interact with the crustacean ecdysone receptor (EcR), we established a method involving 〈em〉in silico〈/em〉 modeling/molecular docking and 〈em〉in vitro〈/em〉 reporter gene assay. Cherry shrimp (〈em〉Neocaridina davidi〈/em〉) EcR (NdEcR) and retinoid X receptor (NdRxR) were identified and cloned for use in this method. A theoretical 3D model of NdEcR ligand-binding domain (LBD) was built 〈em〉in silico〈/em〉 based on sequence homology with the established X-ray structure of insect EcR. The interaction of the NdEcR LBD with ecdysteroids, diacylhydrazine (DAH) pesticides, and other potential EDCs was evaluated using molecular docking programs. The results revealed that the ligand-binding pocket in the NdEcR LBD was flexible and adaptive for accommodating ligands of different shapes. The agonistic and antagonistic activities of the candidate compounds were further assessed by 〈em〉in vitro〈/em〉 reporter gene assay using human cell lines transiently transfected with NdEcR and NdRxR expression plasmids and a reporter plasmid containing synthesized ecdysone response element. The assay was validated by the dose-dependent responses of EcR-mediated gene transcription after treating the transfected cell lines with ecdysteroids, 20-hydroxyecdysone, and ponasterone A. Examination of the candidate compounds using the reporter gene assay revealed restricted functional specificity to ecdysteroids and DAHs. Three of the tested DAH pesticides originally targeting the insect EcR were found to be weak agonists and strong antagonists of NdEcR. These results suggest that DAHs are potential EDCs for crustaceans that disrupt their ecdysteroid signals by functioning as EcR agonists or antagonists.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519317758-fx1.jpg" width="272" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Mathieu Gosselin, Gerald J. Zagury〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Field-collected chromated copper arsenate (CCA)-contaminated soils and associated particulate matter (PM) were characterized for their total metal(loid)s content (As, Cr, Cu, Fe, Mn, Ni, Pb and Zn) and physicochemical properties. Copper, Ni, Pb and Zn fractionation (using sequential extraction) and inhalation bioaccessibility (using two lung fluids) of trace elements were assessed in PM samples. In Gamble's solution (GS), low average bioaccessibility (up to 12%) was observed for As, Cu, Mn, and Ni. A strong correlation (〈em〉r〈/em〉 = 0.92, p 〈 0.005, n = 9) between the soluble and exchangeable fraction (F1) and bioaccessibility in GS was observed for Cu. Inhalation bioaccessibility in artificial lysosomal fluid (ALF) was higher for Cu (avg. 78.5 ± 4.2%), Mn (avg. 56.8 ± 12.1%), Zn (avg. 54.8 ± 24.5%) and As (avg. 45.4 ± 18.8%). Strong correlations between inhalation bioaccessibility in ALF and the mobile (i.e. F1+F2) metal fraction were observed for all tested metals (i.e. (Cu (〈em〉r〈/em〉 = 0.95, p 〈 0.005), Ni (〈em〉r〈/em〉 = 0.79, p 〈 0.05), Pb (〈em〉r〈/em〉 = 0.92, p 〈 0.005) and Zn (〈em〉r〈/em〉 = 0.98, p 〈 0.005)), n = 9). The oxidative potential (OP) of PM was also assessed using an ascorbate (AA) depletion assay (OP〈sub〉AA〈/sub〉). Mobile Cu fractions were deemed to be the main factor influencing OP〈sub〉AA〈/sub〉 ((F1 (〈em〉r〈/em〉 = 0.99, p 〈 0.005), F2 (〈em〉r〈/em〉 = 0.97, p 〈 0.005)), n = 9) in PM samples. A strong correlation (〈em〉r〈/em〉 = 0.94, p 〈 0.005, n = 10) was also observed between Cu bioaccessibility in GS and OP〈sub〉AA〈/sub〉.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519317813-fx1.jpg" width="357" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Raougina-Laouisa Bachour, Oksana Golovko, Martin Kellner, Johannes Pohl〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Pharmaceuticals are emerging as environmentally problematic compounds. As they are often not appropriately removed by sewage treatment plants, pharmaceutical compounds end up in surface water environments worldwide at concentrations in the ng to μg L〈sup〉−1〈/sup〉 range. There is a need to further explore single compound and mixture effects using e.g. 〈em〉in vivo〈/em〉 test model systems. We have investigated, for the first time, behavioral effects in larval zebrafish (〈em〉Danio rerio〈/em〉) exposed to a binary mixture of an antidepressant drug (citalopram) and a synthetic opioid (tramadol). Citalopram and tramadol have a similar mode of action (serotonin reuptake inhibition) and are known to produce drug-drug interactional effects resulting in serotonin syndrome (SS) in humans. Zebrafish embryo-larvae were exposed to citalopram, tramadol and 1:1 binary mixture from fertilization until 144 h post-fertilization. No effects on heart rate, spontaneous tail coiling, or death/malformations were observed in any treatment at tested concentrations. Behavior (hypoactivity in dark periods) was on the other hand affected, with lowest observed effect concentrations (LOECs) of 373 μg L〈sup〉−1〈/sup〉 for citalopram, 320 μg L〈sup〉−1〈/sup〉 for tramadol, and 473 μg L〈sup〉−1〈/sup〉 for the 1:1 mixture. Behavioral EC〈sub〉50〈/sub〉 was calculated to be 471 μg L〈sup〉−1〈/sup〉 for citalopram, 411 μg L〈sup〉−1〈/sup〉 for tramadol, and 713 μg L〈sup〉−1〈/sup〉 for the 1:1 mixture. The results of this study conclude that tramadol and citalopram produce hypoactivity in 144 hpf zebrafish larvae. Further, a 1:1 binary mixture of the two caused the same response, albeit at a higher concentration, possibly due to SS.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Jae Kwan Kim, Adnan Khan, Seongha Cho, Jinhyuk Na, Yeseung Lee, Geul Bang, Wook-Joon Yu, Ji-Seong Jeong, Sun Ha Jee, Youngja H. Park〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉High exposure to bisphenol A (BPA) in children has been associated with the outcomes of several diseases, including those related to developmental problems. To elucidate the mechanism of BPA mediated developmental toxicity, plasma and urine from rats exposed to BPA was analyzed with high resolution metabolomics, beginning from post-natal day 9, for 91 days. Female and male rats were orally administered 5 different BPA doses to elucidate dose- and sex-specific BPA effects. Regarding dose-specific effects, multivariate statistical analysis showed that metabolic shifts were considerably altered between 5, 50 and 250 mg BPA/kg bw/day in treated rats. A nonmonotonicity and monotonicity between BPA dose and metabolic response were major trajectories, showing overall metabolic changes in plasma and urine, respectively. Metabolic perturbation in the steroid hormone biosynthesis pathway was significantly associated with dose- and sex-specific BPA effects. Intermediate metabolites in the rate-limiting step of steroid hormone biosynthesis down-regulated steroid hormones in the 250 mg treatment. Further, our study identified that BPA increased urinary excretion of vitamin D〈sub〉3〈/sub〉 and decreased its concentration in blood, suggesting that perturbation of vitamin D〈sub〉3〈/sub〉 metabolism may be mechanistically associated with neurodevelopmental disorders caused by BPA. Three metabolites showed a decrease in sex difference with high BPA dose because female rats were more affected than males, which can be related with early puberty onset in female. In brief, the results demonstrated that BPA induces dose- and sex-specific metabolic shifts and that perturbation of metabolism can explain developmental problems.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519316935-fx1.jpg" width="500" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Jinyue Liu, Xiaoqin Li, Xing Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The abuse of ciprofloxacin (CIP) may cause serious side effects and the mechanisms underlying these effects remain unclear. Here, we determinate the 48 h, 72 h and 96 h 〈em〉LC〈/em〉〈sub〉〈em〉50〈/em〉〈/sub〉 values of CIP to 〈em〉Drosophila melanogaster〈/em〉 and demonstrate a series of adverse effects after 〈em〉D. melanogaster〈/em〉 was exposed to CIP at a sublethal concentration (3.2 mg mL〈sup〉−1〈/sup〉). Treated individuals showed shorter lifespan, delayed development and many of the treated larvae failed to pupate or hatch. Smaller body size was observed at every life stage when exposed to CIP and the size of pupae, the weight of third-instar larvae exhibited a perfectly dose-response relationship that the larger concentration exposed to, the smaller body size or lighter weight is. Moreover, reduction in fat body cell viability, elevated oxidative stress markers (SOD and CAT) and down-regulation of 〈em〉diap1〈/em〉, 〈em〉ex〈/em〉, two target genes of Yorkie (Yki), was observed in response to CIP exposure. Most importantly, we found two types of black spot in 〈em〉Drosophila〈/em〉 and the proportion of larvae with a black spot was positively related to the treatment dose, which is new in the field. This study provides a scientific basis for the potential harm caused by abuse of quinolones with the goal of urging cautious use of antibiotics.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519317667-egi10LJ69F2H02.jpg" width="500" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Abdullah M. Al-Salem, Quaiser Saquib, Maqsood A. Siddiqui, Javed Ahmad, Rizwan Wahab, Abdulaziz A. Al-Khedhairy〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Tricresyl phosphate (TCP) is one of the organophosphorus flame retardants (OPFRs) used as plasticizer in consumer products and mixed as a lubricant in commercial jet engine oil, reportedly induce neurotoxicity and aerodynamic syndrome. No studies have been attempted so far on TCP to induce hepatotoxicity in human cells. This study for the first time confirms the hepatotoxic potential and activation of cancer pathways in TCP treated human hepatocellular cells (HepG2). MTT and NRU data showed 39.3% and 49.85% decline in HepG2 survival when exposed to the highest concentration of TCP (400 μM) for 3 days. Comet assay showed 27.1-fold greater DNA damage in cells treated with TCP (400 μM). Flow cytometric analysis revealed an upsurge in the intracellular reactive oxygen species (ROS) and nitric oxide (NO) production in cells, affirming oxidative stress. TCP (400 μM) exposure resulted in 27% reduction in Rh123 fluorescence, indicating dysfunction of mitochondrial membrane potential (〈em〉ΔΨm〈/em〉). Cell cycle analysis exhibited 62.53% cells in the subG1 apoptotic phase after TCP (400 μM) treatment, also a massive increase in Ca〈sup〉2+〈/sup〉 influx validate the on-set of apoptosis in cells. Immunofluorescence of TCP exposed cells showed activation of p53, caspase3, caspase9 reaffirming the involvement of mitochondrial-dependent intrinsic apoptotic signaling. qPCR array of 84 genes unravel the transcriptomic alterations in HepG2 cells after TCP treatment. mRNA transcripts of 〈em〉ATP5A1〈/em〉, 〈em〉GADD45A, IGFBP5, SOD1, STMN1〈/em〉 genes were prominently upregulated providing candid evidence on TCP mediated activation of human cancer pathways to orchestrate the apoptotic death of HepG2 cells, specifying hepatotoxic potential of TCP.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519317436-fx1.jpg" width="461" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Na Chen, Shuangyi Tao, Keke Xiao, Sha Liang, Jiakuan Yang, Lizhi Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Sewage sludge dewatering is an efficient approach to reduce the volume of sludge for the subsequent disposal. In this study, a novel one-step acidification sludge dewatering method was developed with using oxalic acid as a conditioner. In laboratory-scale experiments with the dosage of 200 mg/g dry solid (DS), the normalized capillary suction time and the specific resistance to filtration were respectively decreased by 78.7% and 60.0% after 30 min of oxalic acid conditioning, much more efficient than those conditioned with sulfuric acid and hydrochloric acid at the same pH value. This superior dewatering performance was attributed to two factors. One was that oxalic acid could more efficiently promote the hydrolysis of polysaccharide, especially pectins, to release bound water. The other was that OA could dissolve more Fe〈sup〉3+〈/sup〉 and Al〈sup〉3+〈/sup〉, as well as form precipitate with Ca〈sup〉2+〈/sup〉 in sludge, which may act as flocculants or co-precipitator for the subsequent sludge particles coagulation. In pilot-scale experiments, the water content of oxalic acid conditioned sludge cake was reduced to 60% under the optimum conditions, while the reagent cost was as low as 110.0 USD/t DS. This work provides a cost-effective and easy-operated sewage sludge disposal technique, and also sheds light on the potential of oxalic acid in environmental waste treatment.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519318223-fx1.jpg" width="279" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Manuel Sierra Aragón, Yasuo Mitsui Nakamaru, Minerva García-Carmona, Francisco Javier Martínez Garzón, Francisco José Martín Peinado〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The addition of organic amendment in soils affected by residual pollution of potentially harmful elements (PHEs) is evaluated. The area was polluted twenty years ago and remediation actions were intensively applied, but evidence of pollution are still detected in some sectors. The amendment application produces significant changes in the main soil properties and modifies the mobility and availability of the pollutants. In general, Cu, Zn, Cd and Pb, showed a significant reduction in soluble and exchangeable forms after the vermicompost addition (percentage of reduction ranging from 59% for soluble Pb to 95% for exchangeable Zn), both in highly (UVS) as in moderately (VS1) polluted soils. This reduction is strongly related to the rise in OC content and pH. Arsenic presented no significant reduction or even an increase in soluble forms in moderately polluted soils (VS1), where the competing effects of OC and phosphorous could be responsible for this increase. Pb also showed an increase in availability after vermicompost application, probably related to the competing effect of Mg〈sup〉2+〈/sup〉 coming from the organic amendment. The less mobile forms (those extracted with oxalic-oxalate, pyrophosphate and EDTA), indicate that vermicompost application reduce medium-long term mobility to similar values of those found in less polluted soils (VS2); anyway, an increase in available forms of Pb and As was detected in some cases, indicating a potential risk of toxicity that should be monitored over time.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Yingjie Dai, Jingjing Li, Dexin Shan〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This study investigated the adsorption of tetracycline (TC) on biochar (BC) derived from waste 〈em〉Auricularia auricula〈/em〉 dregs obtained at different pyrolysis temperatures. The characterization of BC and batch experiment results showed that BC prepared at a higher temperature was more suitable for removing TC, where the maximum adsorption capacities of BC samples prepared at 300 °C, 500 °C, and 700 °C were 7.22 mg/g, 9.90 mg/g, and 11.90 mg/g, respectively. A pseudo-first order kinetics model and Freundlich, Temkin, and Dubinin–Radushkevich isotherm models fitted well to the adsorption data. Liquid film diffusion was the rate-controlling step. In addition, π–π electron donor–acceptor interactions may have played a dominant role in the adsorption mechanism between the enone structure of TC and aromatic C of BC. These results may facilitate further investigations of the adsorption mechanism and optimization of the process.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Joana M.C. Fernandes, Rose Marie O.F. Sousa, Irene Fraga, Ana Sampaio, Carla Amaral, Rui M.F. Bezerra, Albino A. Dias〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The wastewaters from distilleries of winemaking by-products, a scarcely studied type of vinasse, were treated by white-rot fungal strains from species 〈em〉Irpex lacteus〈/em〉, 〈em〉Ganoderma resinaceum〈/em〉, 〈em〉Trametes versicolor〈/em〉, 〈em〉Phlebia rufa〈/em〉 and 〈em〉Bjerkandera adusta〈/em〉. The main objectives of this study were to evaluate fungal performance during vinasse biodegradation, their enzyme patterns and ecotoxicity evolution throughout treatment. Despite all strains were able to promote strong (〉80%) dephenolization and reduction of total organic carbon (TOC), 〈em〉P. rufa〈/em〉 was less affected by vinasse toxicity and exhibit better decolorization. In batch cultures at 28 °C and pH 4.0, the first phase of 〈em〉P. rufa〈/em〉 biodegradation kinetics was characterized by strong metabolic activity with simultaneous depletion of TOC, phenolics and sugars. The main events of second phase are the increase of peroxidases production after the peak of laccase activity, and strong color removal. At the end of treatment, it was observed highly significant (p 〈 0.001) abatement of pollution parameters (83–100% removal). Since water reclamation and reuse for e.g. crop irrigation is a priority issue, vinasse ecotoxicity was assessed with bioindicators representing three different phylogenetic and trophic levels: a marine bacterium (〈em〉Aliivibrio fischeri〈/em〉), a freshwater microcrustacean (〈em〉Daphnia magna〈/em〉) and a dicotyledonous macrophyte (〈em〉Lepidium sativum〈/em〉). It was observed significant (p 〈 0.05) reduction of initial vinasse toxicity, as evaluated by these bioindicators, deserving special mention an almost complete phytotoxicity elimination.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): David Nos, Joan Navarro, Enric Saiz, Juan C. Sanchez-Hernandez, Montserrat Solé〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Tetrabromobisphenol A (TBBPA), a brominated flame retardant used in synthetic polymers and electronics, is present in the aquatic environment and recent evidence suggests it can be potentially biomagnified in the marine ecosystem. However, the toxicity of TBBPA in the marine biota has not been investigated in detail. In this study we aimed to understand the role of carboxylesterases (CEs) in xenobiotic metabolism under the exposure of marine organisms to a chemical of environmental concern, TBBPA. Specifically, we tested for 〈em〉in vitro〈/em〉 inhibition of CE activity in a range of marine organisms covering different ecological niches, from species from low (mussels and copepods), medium (sardines and anchovies) and high trophic levels (tuna). The results revealed that the highest inhibition of CE activity to 100 μM TBBPA was recorded in mussels (66.5% inhibition) and tunids (36.3–76.4%), whereas copepods and small pelagic fish showed comparatively lower effects (respectively, 30% and 36.5–55.6%). Our results suggest that CE-mediated detoxification and physiological processes could be compromised in TBBPA-exposed organisms and could ultimately affect humans as many of them are market species.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519318168-fx1.jpg" width="381" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Mohammad Hosein Sinkakarimi, Eisa Solgi, Abasalt Hosseinzadeh Colagar〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Earthworms are often used as test subjects in toxicological studies, due to their ubiquitousness and sensitivity to contaminant exposure. Such testing is typically conducted using 〈em〉Eisenia fetida〈/em〉 as the test subject, but continued use of 〈em〉E. fetida〈/em〉 (eco) toxicology is questionable. Therefore, in this study three earthworm species, 〈em〉Aporrectodea rosea, Aporrectodea trapezoides〈/em〉 and 〈em〉E. fetida〈/em〉, were exposed to lethal and sublethal concentrations of cadmium (Cd) and lead (Pb) nitrate in artificial soil for 7, 14 and 28 days. A biomarker of genotoxicity (TUNEL assay), biochemical markers [malondialdehyde (MDA) and total antioxidant capacity (TAC)], weight loss, lethal toxicity (LC〈sub〉50〈/sub〉) and subcellular partitioning were assessed. Cadmium and Pb caused significant inhibition in TAC and growth and significant increases in DNA damage and lipid peroxidation in the earthworms. Acute toxicity rank (14 days) for both Cd and Pb were 〈em〉E. fetida〈/em〉 〉 〈em〉A. trapezoides〈/em〉 〉 〈em〉A. rosea〈/em〉. Subcellular partitioning of Cd and Pb in the earthworms were cytosol 〉 debris 〉 granules and debris 〉 granules 〉 cytosol, respectively. Comparison of biomarker responses between study species showed that 〈em〉E. fetida〈/em〉 proved to be less susceptible to Cd and Pb exposure than 〈em〉A. rosea〈/em〉 and 〈em〉A. trapezoides〈/em〉. Therefore, this study confirms that 〈em〉A. rosea〈/em〉 and 〈em〉A. trapezoides〈/em〉 are more suitable as subjects than 〈em〉E. fetida〈/em〉 for the soil toxicity tests, because of both their greater susceptibility to toxicants and in their abundance in the field.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519318193-fx1.jpg" width="500" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Yahya Jani, Juris Burlakovs, Anna Augustsson, Marcia Marques, William Hogland〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉More than 34 old glasswork sites in the southeastern part of Sweden pose a permanent threat to human and environmental health due to the presence of toxic trace elements in open dumps with glass waste. The possibility of leaching of trace elements from different fractions of the disposed waste needed to be assessed. In the present investigation, leachate from a mixture of soil and waste glass of particle sizes of less than 2 mm (given the name fine fraction) was characterized by analyzing the pH (7.3), total organic content (TOC 〈 2%), organic matter content (4.4%), moisture content (9.7%), chemical oxygen demand (COD, 163 mg/kg) and trace elements content, being the values in accordance to the Swedish guidelines for landfilling of inert materials. However, very high trace elements content was found in the fine fraction as well as in all colors of waste glass, whose values were compatible to hazardous waste landfill class. Tests with 〈em〉Lepidium sativum〈/em〉 growing in the fine fraction as substrate revealed chronic toxicity expressed as inhibition of root biomass growth in 11 out of 15 samples. Additionally, leachate from fine fractions posed acute toxicity to genetically modified 〈em〉E. coli〈/em〉 (Toxi-Chromotest). This study highlights the importance of combining physicochemical characterization with toxicity tests for both solid waste and leachate obtained from different waste fractions for proper hazardousness assessment supporting decision making on remediation demands.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Chi-Hang Chow, Kelvin Sze-Yin Leung〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Permanganate/bisulfite (PM/BS) is a relatively new advanced oxidation process that can degrade organic micropollutants at extraordinary high rates. In this study, the degradability of PM/BS process towards different representative types of compounds was studied by investigating the kinetics, reaction site specificity and transformation chemistry. Acesulfame (ACE) and carbamazepine (CBZ) were two typical compounds containing olefinic moieties. Sucralose (SUC) was selected as a reference compound, and it is without aromatic and olefinic moieties. The kinetics results indicated that ACE and CBZ were effectively degraded while SUC was not. Preferred reaction sites of Mn〈sup〉3+〈/sup〉 species was elucidated by identification of the ACE-transformation products (TPs) and CBZ-TPs with UHPLC-QTOF-MS. Seventeen ACE-TPs including two new compounds and eleven CBZ-TPs produced during the PM/BS process were identified and characterized. Transformation pathways revealed that cleavage of olefinic double bonds was the main reaction mechanism. Chemical structures containing electron-donating groups preferentially reacted with electrophilic Mn〈sup〉3+〈/sup〉 species during the process. In addition, transformation products of ACE and CBZ during PM/BS process did not induce higher toxicity. This study provides a preliminary interpretation on the selectivity of PM/BS process according to the micropollutants’ chemical structures, which hope to shed light on the future development of PM/BS treatment.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Da Li, Linlin Huang, Tongtong Liu, Jia Liu, Liang Zhen, Jing Wu, Yujie Feng〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Electrochemical reduction of CO〈sub〉2〈/sub〉 has been demonstrated as one of the promising technologies to reduce the greenhouse effect. In this study, nano-prism assembled hierarchical CuO microspheres (Prism-CuO) were designed and used for CO〈sub〉2〈/sub〉 electroreduction. The Prism-CuO coated gas diffusion electrode showed high activity for CO〈sub〉2〈/sub〉-to-formate conversion with overpotential as low as ∼200 mV, and achieved maximum faradaic efficiency of 65.1% at −1.6 V 〈em〉vs〈/em〉. Ag/AgCl. Moreover, it maintained the stable performance for continuous 20 h of electrolysis. The better performance was mainly attributed to the unique prism feature as it provided abundant corner- and edge-based low-coordinated active reaction sites. These sites could further arouse strong local-electric field to lower the barrier of CO〈sub〉2〈/sub〉 adsorption and motivate CO〈sub〉2〈/sub〉 activation by accelerating charges transfer process. The result implied designing the nano-prism constructed hierarchical framework would be an efficient strategy to develop the advanced electrocatalyst for efficient CO〈sub〉2〈/sub〉 reduction in aqueous solution.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519317515-fx1.jpg" width="301" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Mario Ančić, Ana Huđek, Iva Rihtarić, Mario Cazar, Višnja Bačun-Družina, Nevenka Kopjar, Ksenija Durgo〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Waste landfills represent a global problem, which is more pronounced in developing countries because of the lack of resources to implement procedures that include separation and waste processing. The aim of this research was to analyze leachate and ground waters samples at the site, upstream and downstream from the landfill during different year seasons on a registered non-hazardous waste dump and to conduct physico-chemical and biological assays to determine potential risk for the ecosystem. Potential cytotoxic, prooxidative and mutagenic effects of leachates and water samples were evaluated on human laryngeal cell line (HEp2). Leachates collected at landfill site caused genotoxic effect and had a higher pH, chemical oxygen demand (COD), biochemical oxygen demand (BOD) and elevated concentrations of phosphorus, chloride, nitrogen compounds and sulphate. Genotoxicity of the leachate was increased in samples collected in dry and warm period of the year. These results are in accordance to the physico-chemical analysis which revealed that during summer period, because of intense degradation process at high temperatures increased concentrations of different chemicals can be found in leachate. Groundwater collected downstream and upstream from landfill did not show statistically significant (geno)toxic effect, irrespective of the sampling season. Chemical analysis revealed that all compounds in groundwater were below permitted values. Purification process at landfill is effective and compounds that reach groundwater do not represent a toxicological threat.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Cong Liu, Fangfang Ma, Jonas Elm, Zihao Fu, Weihao Tang, Jingwen Chen, Hong-Bin Xie〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Atmospheric oxidation of NH〈sub〉〈em〉x〈/em〉〈/sub〉-containing (〈em〉x〈/em〉 = 1, 2) compounds can produce N-center radicals, a precursor of toxic nitrosamines. The reaction rate constant (〈em〉k〈/em〉〈sub〉O2〈/sub〉) with O〈sub〉2〈/sub〉 has been considered as an important parameter to determine the nitrosamines yield in the subsequent reactions of N-center radicals. However, available 〈em〉k〈/em〉〈sub〉O2〈/sub〉 values of N-center radicals are limited. Here, a three-step scheme including mechanistic analysis and kinetics calculation of the reactions of 28 various N-center radicals with O〈sub〉2〈/sub〉, and model development was taken to solve the 〈em〉k〈/em〉〈sub〉O2〈/sub〉 data shortage. Mainly employed tools include highly cost-expensive coupled-cluster theory (CCSD(T)), kinetic model and statistics. The results indicate that the direct H-abstraction pathway is the most favorable for the reactions of all considered N-center radicals with O〈sub〉2〈/sub〉. The specific molecular conformation and the C–H bond energy of the N-center radicals are two important factors to determine 〈em〉k〈/em〉〈sub〉O2〈/sub〉 values. Based on the mechanistic understanding of 〈em〉k〈/em〉〈sub〉O2〈/sub〉 values, a quantitative structure-activity relationship (QSAR) model of 〈em〉k〈/em〉〈sub〉O2〈/sub〉 values was developed. The model has satisfactory goodness-of-fit, robustness and predictive ability. The determined 〈em〉k〈/em〉〈sub〉O2〈/sub〉 values and the 〈em〉in silico〈/em〉 methods provide a scientific base for assessing formation risk of toxic nitrosamines in the atmosphere.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519316327-fx1.jpg" width="457" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Joseph T. Buchman, Thomas Pho, Rebeca S. Rodriguez, Z. Vivian Feng, Christy L. Haynes〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Here, we investigate the impact of iron oxide nanoparticles (IONPs) and mesoporous silica-coated iron oxide nanoparticles (msIONPs) on 〈em〉Shewanella oneidensis〈/em〉 in an aerobic environment, which is likely the main environment where such nanoparticles will end up after use in consumer products or biomedical applications. Monitoring the viability of 〈em〉S. oneidensis〈/em〉, a model environmental organism, after exposure to the nanoparticles reveals that IONPs promote bacterial survival, while msIONPs do not impact survival. These apparent impacts are correlated with association of the nanoparticles with the bacterial membrane, as revealed by TEM and ICP-MS studies, and upregulation of membrane-associated genes. However, similar survival in bacteria was observed when exposed to equivalent concentrations of released ions from each nanomaterial, indicating that aqueous nanoparticle transformations are responsible for the observed changes in bacterial viability. Therefore, this work demonstrates that a simple mesoporous silica coating can control the dissolution of the IONP core by greatly reducing the amount of released iron ions, making msIONPs a more sustainable option to reduce perturbations to the ecosystem upon release of nanoparticles into the environment.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519317357-fx1.jpg" width="354" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Siqi Liu, Ruiqian Liu, Yonghao Zhang, Weiqing Han, Jiansheng Li, Xiuyun Sun, Jinyou Shen, Lianjun Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Inability to remove biologically toxic and persistent contaminants is a critical issue in traditional water treatment processes. In this study, a novel 3D macroporous RuO〈sub〉2〈/sub〉 (3D-RuO〈sub〉2〈/sub〉) electrode with uniform and interconnected cavities has been fabricated via templated electrodeposition approach for treatment of persistent pyrazole. The physicochemical properties of the electrodes are characterized by means of SEM, BET, XRD, LSV and CV measurements. The results show that structural features of the 3D-RuO〈sub〉2〈/sub〉 play important roles in the electrocatalysis performance. Thanks to the abundant crystal defect sites, 3D-RuO〈sub〉2〈/sub〉 electrode possesses more mesopores within the skeleton, resulting in 17.9 and 2.2 times larger specific surface area compared to traditional flat thermal-deposited (TF-RuO〈sub〉2〈/sub〉) and electrodeposited RuO〈sub〉2〈/sub〉 (EF-RuO〈sub〉2〈/sub〉) respectively. At a current density of 5 mA cm〈sup〉−2〈/sup〉, the pyrazole removal rate on 3D-RuO〈sub〉2〈/sub〉 is 1.7 times and 1.3 times that of TF-RuO〈sub〉2〈/sub〉 and EF-RuO〈sub〉2〈/sub〉. The energy consumption for 50% of pyrazole removal on 3D-RuO〈sub〉2〈/sub〉 is 0.05 kWh g〈sup〉−1〈/sup〉pyrazole, much lower than that of TF-RuO〈sub〉2〈/sub〉 (0.11 kWh g〈sup〉−1〈/sup〉pyrazole) and EF-RuO〈sub〉2〈/sub〉 (0.075 kWh g〈sup〉−1〈/sup〉pyrazole). The improved removal performance of 3D-RuO〈sub〉2〈/sub〉 electrode is attributed to its strong electro-adsorption capacity (270.3 μg cm〈sup〉−2〈/sup〉), leading to enhanced mass transfer of pollutants to the electrode surface. The mass transfer coefficient (κ〈sub〉m〈/sub〉) is estimated as 2.4 × 10〈sup〉−6〈/sup〉 m s〈sup〉−1〈/sup〉 for 3D-RuO〈sub〉2〈/sub〉, which is 3.9 and 2.3 times as much as that of TF-RuO〈sub〉2〈/sub〉 and EF-RuO〈sub〉2〈/sub〉. Finally, contribution of different electron transfer approaches to pyrazole degradation under anodic polarization was investigated by ROS scavenging experiments.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519316959-fx1.jpg" width="500" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Ruichang Zhang, Haibo Zhang, Chen Tu, Yongming Luo〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The complexity of natural dissolved organic matter (DOM) motivates the determination of how DOM from diverse sources affects the environmental behaviors of engineered nanoparticles. Here, three types of DOM, DOM extracted from swine manure (SWDOM), sludge (SLDOM) and sediment (SEDOM), were characterized, and their effects on the transport of titanium dioxide nanoparticles (TiO〈sub〉2〈/sub〉 NPs, 30 nm in diameter) were evaluated and compared with those of humic acid (HA). Characterization tests showed differences in the aromaticity and weight-average molecular weight (M〈sub〉w〈/sub〉) properties among the three extracted DOM solutions, and greater distinctions were found between the extracted DOM and HA. All the extracted DOM facilitated TiO〈sub〉2〈/sub〉 NPs transport in acidic porous media. Nevertheless, the enhancing effects varied among the different extracted DOM types. SWDOM had a promoting effect on TiO〈sub〉2〈/sub〉 NPs mobility that was equivalent to that of SEDOM and much higher than that of SLDOM. However, the facilitating effects of all three extracted DOM types were limited compared to that of HA. Based on the combined analysis of DOM properties and TiO〈sub〉2〈/sub〉 NPs transport behaviors, it could be concluded that aromaticity and M〈sub〉w〈/sub〉 were the key properties determining the limited promoting effects of DOM on TiO〈sub〉2〈/sub〉 NPs mobility, and the specific UV absorbance at 280 nm (normalized by concentration, SUVA〈sub〉280〈/sub〉) was a facile and useful indicator of the DOM-promoted transport of TiO〈sub〉2〈/sub〉 NPs. These findings revealed that transport potential in the presence of DOM would be overestimated if either HA or fulvic acid were chosen as the DOM model in studies.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Dipti Karmakar, Pratap Kumar Padhy〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The present study was performed on 〈em〉Shorea robusta〈/em〉 Gaertn., 〈em〉Acacia auriculiformis〈/em〉 Benth., 〈em〉Eucalyptus globulus〈/em〉 Labill., 〈em〉Azadirachta indica〈/em〉 A. Juss in two tropical forests [including one (Barjora), situated adjacent to heavy pollution sources and the other, as control, Ballavpur Wildlife Sanctuary (BWLS)] of West Bengal, India, to measure the heavy metals accumulation capacity in their leaves and their levels of tolerance in a polluted environment. Site wise and seasonal variations in air pollution tolerance index (APTI) and anticipated performance index (API) were assessed in the aforesaid four plants. Highest APTI value was observed in 〈em〉S. robusta〈/em〉 (34.62 ± 1.47) at polluted site during winter. 〈em〉S. robusta〈/em〉 anticipated as an excellent performer on the basis of API score in all the three seasons in BWLS. The metal accumulation index (MAI) values ranged from 3.06 to 7.68 and 9.48–9.82; 2.65–4.96 and 4.29–6.08; 3.35–8.14 and 5.04–11.65; 3.59–4.64 and 5.21–7.98 at BWLS and Barjora forest for 〈em〉S. robusta〈/em〉, 〈em〉A. auriculiformis〈/em〉, 〈em〉E. globulus〈/em〉 and 〈em〉A. indica〈/em〉 respectively. Two-way ANOVA test showed a site and season wise significant difference in the biochemical and physiological parameters between the two forests. The results indicated that air pollution played an important role, which affected the biochemical and physiological parameters of plants in tropical forest located at a polluted site. The species with highest MAI and APTI value could be used in sound green space management for reducing the levels of atmospheric pollution. Higher levels of ascorbic acid content, at polluted site as compared to control site, were an indication of stress condition.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Jia-cheng Xu, Li-min Huang, Chengyu Chen, Jing Wang, Xin-xian Long〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Lead can be immobilized in contaminated soils by phosphate rock (PR) amendment, but its efficiency is generally limited by low solubility of PR. Our study aimed to elucidate whether phosphate solubilizing bacteria (PSB) can promote Pb immobilization through PR solubilization. Results showed that 〈em〉P. ananatis〈/em〉 HCR2 and 〈em〉B. thuringiensis〈/em〉 GL-1 could effectively solubilize PR by producing citric, glucose, and 〈em〉α〈/em〉-Ketoglutaric acids. In broth assay, phosphate solubilized from PR by PSB rapidly reacted with Pb〈sup〉2+〈/sup〉 and formed insoluble lead compounds, as confirmed by scanning electron microscope, energy dispersive X-ray, and X-ray photoelectron spectroscopy. Pot experiment using lettuce (〈em〉Lactuca sativa〈/em〉 L.) and diffusive gradients in thin films (DGT) verified the effectiveness of soil remediation using PR amendment and PSB inoculation, as plant shoot biomass and net photosynthetic rate as well as soil bioavailable phosphate concentration have significantly increased, while the phytoavailability of Pb, Cd, and Zn greatly reduced. This study suggested that PR amendment combined with PSB inoculation could be applied for remediation of agricultural fields contaminated with multiple heavy metals.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519317643-fx1.jpg" width="500" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Peng Xu, Hao Xu, Dayang Zheng, Jingwei Ma, Baolin Hou〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A novel system combined with photocatalytic fuel cell and electrochemical system assisted by reverse electrodialysis (PREC) is proposed for H〈sub〉2〈/sub〉O〈sub〉2〈/sub〉 production and electricity generation. Results demonstrated the H〈sub〉2〈/sub〉O〈sub〉2〈/sub〉 concentration increased gradually with time and reached around 940 mg/L at 24 h. The optimum air flow rate was 15 L/min. The current efficiency was 31.3%. The maximum short-circuit current density, maximum open-circuit voltage and maximum power density were 0.95 mA/cm〈sup〉2〈/sup〉, 1.52 V and 68 W/m〈sup〉2〈/sup〉. The salinity-driven potential, created with the five pairs of the HC and LC cells in the PREC, was calculated to be 0.72 V. Additionally, the energy efficiency (η〈sub〉E〈/sub〉) was 40.5%. The integrated system is confirmed to be serviced as an efficient technology for H〈sub〉2〈/sub〉O〈sub〉2〈/sub〉 electro-genneration and salinity-gradient energy utilization simultaneously.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519317333-egi10QJ9KXF1H8.jpg" width="311" alt="Image 10918" title="Image 10918"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Yuzhi Liu, Yu Gao, Bing Yao, Donglei Zou〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Nano micro-electrolysis materials (nMETs) have been used to degrade refractory pollutants in batch experiments. The reasonable formation mechanism of nMETs was given through DMXY digital biomicroscopy. Based on the kinetic data of Chlortetracycline (CTC) removal by nMETs in batch experiments, combined with the binomial distribution equation of CTC reduction by nano materials an experimental-scale fluidized bed (ESFB) was designed. The effects of CTC removal performance, pH and iron ion concentration were investigated. Under pure CTC solution environment, the experimental data showed that the average removal rates of CTC by nMET and nano micro-electrolysis material with loading copper (Cu-nMET) are 90.0% and 95.7% in ESFB, respectively. In the presence of nitrate, although the consumption of two kinds of nano-materials increased, their removal efficiencies of pollutants have 2.2%, 0.2% increase compared with the nitrate-free ESFB. At the same time, the CTC degradation pathway and the enhanced removal mechanism by Cu-nMET was proposed. Through microelectrolysis reaction, complexation reaction and the active substances produced, the intermediate products can be degraded completely to NH〈sub〉4〈/sub〉〈sup〉+〈/sup〉, CO〈sub〉2〈/sub〉, H〈sub〉2〈/sub〉O and so on. This study aims to provide a theoretical basis for the environmental application of nMETs.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519317679-fx1.jpg" width="395" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Marianna Pinzone, France Damseaux, Loïc N. Michel, Krishna Das〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉The Mediterranean Sea remains a complex system for mercury (Hg) cycling and accumulation in marine vertebrates. The extremely high levels these animals present demand for an urgent understanding of such processes and the development of new analytical techniques that go beyond the simple contamination monitoring. It was often proposed that prey selection or habitat use may affect Hg contamination in animals; however, it was never possible to measure which factor influences more rates and pathways of contamination. In this paper, we directly integrate toxicological information (Hg levels) and ecological tracers (stable isotopes of C, N and S) into a common data analysis framework (isotopic niches), with the aim of quantifying the influence of species’ trophic behaviour on Hg contamination. The analysis was conducted on skin biopsies of fin whales 〈em〉Balaenoptera physalus〈/em〉, long-finned pilot whales 〈em〉Globicephala melas〈/em〉 and sperm whales 〈em〉Physeter microcephalus.〈/em〉 Their different trophic modes and residency in the area make them model species for the analysis of Hg accumulation along NWMS food webs. We measured Total Hg (T-Hg) concentrations through absorbance spectrometry with the DMA80 Milestone. Carbon, nitrogen and sulphur isotope compositions were measured via mass spectrometry in an IRMS coupled to an Elemental Analyser (EA) Isoprime.〈/p〉 〈p〉Comparison of ecological and contamination niches allowed to explain Hg accumulation in Mediterranean marine predators. Factors such as food web complexity, trophic position, hunting distribution or habitat use (e.g., foraging depth) did not influence Hg exposure. It is rather the selection of prey type, which determines the range of potential Hg sources and as a consequence the rates of accumulation in whales’ tissues. A generalist piscivorous species such as the pilot whales will bioaccumulate more Hg than specialised sperm whales feeding mostly on cephalopods.〈/p〉 〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519316728-fx1.jpg" width="353" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Bingqing Zuo, Cong Liu, Renjie Chen, Haidong Kan, Jian Sun, Jing Zhao, Can Wang, Qian Sun, Hongjian Bai〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Scarce evidence existed on the association between short-term exposure to fine particulate matter (PM〈sub〉2.5〈/sub〉) and asthma in China. In this study, we aimed to explore the relationship of PM〈sub〉2.5〈/sub〉 with acute asthma exacerbation in a coastal city of China. Cases of acute asthma exacerbation were identified from hospital outpatient visits in Yancheng, China, from 2015 to 2018. We utilized the generalized additive model linked by a quasi-Poisson distribution to assess the association between PM〈sub〉2.5〈/sub〉 and daily acute asthma exacerbation. Different lag structures were built, and we conducted stratification analyses by gender, age, and season. Two-pollutant models were fitted, and concentration-response (C-R) curves were pooled. A total of 3,520 cases of acute asthma exacerbation were recorded, with a daily average of 3. We observed positive and significant associations of PM〈sub〉2.5〈/sub〉 on lag 1, 2, lag 02, and lag 03 day. For each 10-μg/m〈sup〉3〈/sup〉 increase in PM〈sub〉2.5〈/sub〉 (lag 02), the associated increment in asthma was 3.15% (95% CI: 0.99%, 5.31%). The association remained after adjusting for gaseous co-pollutants. We observed significant PM〈sub〉2.5〈/sub〉-asthma associations in males, patients ≤64 years, and during cold seasons. The C-R curves were positive and almost linear for total and strata-specific associations. In conclusion, this study provided robust evidence on the association of PM〈sub〉2.5〈/sub〉 with acute asthma exacerbation, which may benefit future prevention strategy and policy making.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519317217-fx1.jpg" width="270" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Josilene de Jesus Menk, Ashiley Ingrid Soares do Nascimento, Fernanda Gomes Leite, Renan Angrizani de Oliveira, Angela Faustino Jozala, José Martins de Oliveira Junior, Marco Vinícius Chaud, Denise Grotto〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Residues from pharmaceutical products are found in effluents and in other environmental matrices such as soil and surface waters. Chitin and chitosan are highly adsorptive substances present in mushrooms such as champignon (〈em〉Agaricus bisporus〈/em〉) and shiitake (〈em〉Lentinula edodes〈/em〉). This study evaluated the adsorption efficiency of shiitake and champignon stalks, and shiitake substrate in water contaminated with paracetamol and 17 α-ethynyl estradiol (EE2). Stalks and substrate were dried and ground. Particles were physically evaluated and chemically characterized. Adsorption kinetic and isotherms were carried out for EE2 and paracetamol. Shiitake and champignon stalks had high percentage of porosity, closed and open pores. All bioproducts from mushroom had chemical groups similar to chitosan standard. However, the degree of deacetylation of chitosan was higher in shiitake (28.3%). In EE2 adsorption kinetics, shiitake and champignon stalks showed 100% removal in 20 and 30 min, respectively. Shiitake substrate showed 80% removal. In paracetamol adsorption kinetics, all bioproducts presented more than 95% removal. In EE2 adsorption isotherm, the maximum adsorption capacities (q〈sub〉max〈/sub〉) to shiitake and champignon stalks and shiitake substrate were 5.62, 18.95 and 0.31 mg〈sub〉EE2〈/sub〉/g, respectively. For paracetamol adsorption isotherm, q〈sub〉max〈/sub〉 to shiitake and champignon stalks were 34.20 and 338.08 mg〈sub〉paracetamol〈/sub〉/g, respectively. In conclusion, shiitake and champignon stalks (specially champignon) had the best results regarding the adsorption of EE2 and paracetamol. Reuse of discarded mushroom waste reduces the environmental impact and can add value to the product.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Leo W.Y. Yeung, Nobuyoshi Yamashita, Jerzy Falandysz〈/p〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Isaac A. Adedara, Michael A. Abiola, Adedayo N. Adegbosin, Ajibola A. Odunewu, Ebenezer O. Farombi〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Several evidences from the literature showed that the coexistence of nickel and zinc in polluted waters is related to the similarity in their geogenic and anthropogenic factors. Although most environmental exposures to metals do not occur singly, there is a paucity of scientific knowledge on the effects of zinc and nickel co-exposure on mammalian reproductive health. The present study investigated the influence of co-exposure to nickel and zinc on male reproductive function in rats. Experimental rats were co-exposed to environmentally relevant concentrations of waterborne nickel (75 and 150 μg NiCl〈sub〉2〈/sub〉 L〈sup〉−1〈/sup〉) and zinc (100 and 200 μg ZnCl〈sub〉2〈/sub〉 L〈sup〉−1〈/sup〉) for 45 successive days. Subsequently, reproductive hormones were assayed whereas the hypothalamus, epididymis and testes of the rats were processed for the assessment of oxidative stress and inflammation indices, caspase-3 activity and histology. Results indicated that co-exposure to nickel and zinc significantly (p 〈 0.05) abolished nickel-mediated diminution of antioxidant defense mechanisms while diminishing levels of reactive oxygen and nitrogen species and lipid peroxidation in the hypothalamus, epididymis and testes of the exposed rats. Additionally, co-exposure to zinc abated nickel-mediated diminutions in luteinizing hormone, follicle-stimulating hormone, serum and intra-testicular testosterone with concomitant enhancement of sperm production and quality. Further, zinc abrogated nickel-mediated elevation in inflammatory biomarkers including nitric oxide, tumor necrosis factor alpha, interleukin-1 beta as well as caspase-3 activity. The protective influence of zinc on nicked-induced reproductive toxicity was well supported by histological data. Overall, zinc ameliorated nickel-induced reproductive dysfunction 〈em〉via〈/em〉 its anti-oxidant, anti-inflammatory, anti-apoptotic and spermato-protective activities in rats.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Gang Wen, Qiqi Wan, Xiaoli Deng, Ruihua Cao, Xiangqian Xu, Zhuhao Chen, Jingyi Wang, Tinglin Huang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The occurrence of fungi in water supply systems causes many environmental problems (e.g., odor, taste, turbidity, formation of mycotoxins); it has been an area of increasing concern in recent years. Ultraviolet irradiation can inactivate fungi efficiently. However, its reactivation poses further challenges in water purification. The reactivation characteristics of waterborne fungi under different environmental conditions have rarely been reported. In this study, the effects of temperatures and dark delay on the reactivation of three genera of fungal spores (〈em〉Trichoderma harzianum〈/em〉, 〈em〉Aspergillus niger〈/em〉, 〈em〉Penicillium polonicum〈/em〉) were evaluated. The reactivation levels among these fungal spores were compared in phosphate buffer solution (PBS) and in real groundwater. It was found that lower temperature can inhibit the photoreactivation of fungi, whereas higher temperatures would promote the process. A long-term dark delay can inhibit the photoreactivation of fungi effectively. The dark repair of fungal spores almost do not occur neither in PBS nor in real groundwater. Finally, the photoreactivation percentage in real groundwater was higher than that in PBS. This study will provide a basis for controlling the reactivation of fungi in water.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S004565351931714X-fx1.jpg" width="316" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Kai Wang, Yonghong Liu, Zhengguo Song, Di Wang, Weiwen Qiu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The use of degradable chelating agent to enhance phytoextraction is a promising and low-cost method for remediation of heavy metals-polluted soil. However, very limited information is available regarding the effect of chelating agent combinations on plant growth and its capacity to extract metals. In this study, a pot experiment was conducted to evaluate the applicability of [N, N]-bis glutamic acid (GLDA), nitrilotriacetic acid (NTA), [S, S]- ethylenediamine disuccinic acid (EDDS), and citric acid (CA) alone and in combination to enhance the phytoextraction efficiency of amaranth (〈em〉Amaranthus hypochondriacus〈/em〉 L.) in two Cd-contaminated agricultural soils (S〈sub〉1〈/sub〉 soil 2.12 mg/kg and S〈sub〉2〈/sub〉 soil 2.89 mg/kg; the environmental standard value of Cd in agricultural soils in China is lower than 0.8 mg/kg). The results showed that, except for EDDS, other treatments had no obvious effect on plant biomass, and even promoted biomass increase to reach 1.06 (S1), 2.07 (S2) g/pot. The increase in total Cd extraction amount by 5 mM of single chelators GLDA and NTA reached 3.87 and 2.81 (S1), and 3.28 and 2.50 (S2) times that of the control group, respectively. For complexed chelating agents, G-N (GLDA + NTA) combinations (GLDA = 3 mM, NTA = 2 mM) extracted the highest amount of Cd compared with other treatments, reaching 0.36 and 0.52 mg/pot (4.50 and 3.71 times that of the control group), respectively. The order of extraction amount was G-N 〉 GLDA 〉 NTA 〉 G-E (GLDA + EDDS) 〉 G-C (GLDA + CA) 〉 CA (5 mM total Cd concentration). Moreover, soil enzyme activity of G-N treatment increased significantly compared to that of the control group, indicating the great application potential of a composite chelating agent relative to a single chelating agent. Therefore, degradable chelators, especially the G-N combination, can effectively increase the available Cd content and greatly enhance the ability of plants to absorb and transport Cd in soils.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Jing Liu, Airong Liu, Wei Wang, Ruofan Li, Wei-xian Zhang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Biodegradation of recalcitrant organic contaminants such as organic dyes is a fundamental challenge in wastewater treatment. We report herein the integration of nanoscale zero-valent iron (nZVI) with membrane bioreactors (nZVI-bio system) to achieve enhanced degradation of Congo red (CR) in wastewater. nZVI pretreatment converts the large and bio-recalcitrant CR molecules into smaller and more biodegradable organic compounds in continuous flow stirred tank reactors (CFSTR). A nZVI-bio system was experimented continuously for 52 d with a color removal efficiency of 99% and a reduction of chemical oxygen demand (COD) from 167 mg L〈sup〉−1〈/sup〉 to less than 70 mg L〈sup〉−1〈/sup〉. However, a conventional biotreatment system treating identical wastewater achieved color removal efficiency of just 30–70% and the COD reduction to 116 mg L〈sup〉−1〈/sup〉. This suggests that integrated nZVI-bio system has potential for the treatment of recalcitrant organic dyes. On-line measurements of pH and redox potential in the CSFTR can be conveniently used to monitor and regulate treatment performance.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519316947-fx1.jpg" width="469" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): A.N. Masliy, A.M. Kuznetsov, G.V. Korshin〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Arsenite is a highly toxic compound present in many water sources around the world. The removal of arsenite from water requires its oxidation to arsenate which is much more amenable to treatment using well attested technologies. Prior research has shown that the oxidation of arsenite by hydroxyl radicals is significantly accelerated in the presence of carbonate ions but the intrinsic mechanisms of the acceleration have not yet been established. The main goal of the present work was to examine the oxidation of arsenite in the framework of the density functional theory, to establish a detailed microscopic level mechanism of interactions between arsenite and hydroxyl radicals and to elucidate the nature of the catalytic effect of carbonate ions. Results of this study demonstrate that the [As(OH)〈sub〉2〈/sub〉CO〈sub〉3〈/sub〉]〈sup〉-〈/sup〉 complex is the thermodynamically most stable species formed in the system H〈sub〉3〈/sub〉AsO〈sub〉3〈/sub〉–CO〈sub〉3〈/sub〉〈sup〉2–〈/sup〉/HCO〈sub〉3〈/sub〉〈sup〉−〈/sup〉–H〈sub〉2〈/sub〉O. Interactions of the hydroxyl radical with the [As(OH)〈sub〉2〈/sub〉CO〈sub〉3〈/sub〉]〈sup〉-〈/sup〉 complex yield the pre-reaction complex [As(OH)〈sub〉3〈/sub〉CO〈sub〉3〈/sub〉]〈sup〉-∗〈/sup〉 in the reaction of subsequent oxidation of arsenite. The structures of the reactants, products and transition states, as well as pre- and post-reaction complexes corresponding to several possible mechanisms of the first stage of As(III) oxidation to As(IV) intermediate using hydroxyl radicals in the absence and in the presence of [As(OH)〈sub〉2〈/sub〉CO〈sub〉3〈/sub〉]〈sup〉-〈/sup〉, were determined in this study. The data demonstrate that the arsenite-carbonate complexes [As(OH)〈sub〉2〈/sub〉CO〈sub〉3〈/sub〉]〈sup〉-〈/sup〉 are characterized by a significantly lower activation energy of the first oxidation stage under the action of a hydroxyl radical (2.8 kcal/mol) compared to that for the free arsenite H〈sub〉3〈/sub〉AsO〈sub〉3〈/sub〉 (13.6 kcal/mol).〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S004565351931690X-fx1.jpg" width="339" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Yumeng Qi, Ruijuan Qu, Jiaoqin Liu, Jing Chen, Gadah Al-Basher, Nouf Alsultan, Zunyao Wang, Zongli Huo〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The degradation of flumequine (FLU) in aqueous solution by ultraviolet (UV)-activated peroxymonosulfate (PMS) was investigated in this work. Under the conditions of [PMS]〈sub〉0〈/sub〉:[FLU]〈sub〉0〈/sub〉 = 1:1, T = 25 ± 2 °C, pH = 7.0 ± 0.1, nearly complete removal of FLU was achieved after 60 min. The effects of various operating parameters, including oxidant doses, pH, the presence of typical ions (NH〈sub〉4〈/sub〉〈sup〉+〈/sup〉、Mg〈sup〉2+〈/sup〉、Fe〈sup〉3+〈/sup〉、Cl〈sup〉−〈/sup〉、NO〈sub〉3〈/sub〉〈sup〉−〈/sup〉、HCO〈sub〉3〈/sub〉〈sup〉−〈/sup〉) and humic acid were evaluated. It was found that the pseudo-first-order rate constants of FLU degradation increased with increasing PMS dosage and decreasing solution pH. The presence of Mg〈sup〉2+〈/sup〉 could accelerate FLU removal, while Fe〈sup〉3+〈/sup〉, HCO〈sub〉3〈/sub〉〈sup〉−〈/sup〉, NO〈sub〉3〈/sub〉〈sup〉−〈/sup〉 and HA inhibited the reaction. Moreover, the degradation of FLU in different water matrices were also explored, and the removal followed the order of Tap water 〉 Ultrapure water 〉 River water 〉 Secondary clarifier effluent. According to the control and radical quenching experiment results, direct photolysis and reactive radicals (SO〈sub〉4〈/sub〉〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/rad"〉〈sup〉-〈/sup〉 and HO〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/rad"〉) contributed mainly to FLU degradation in the UV/PMS system. Initial FLU molecule underwent reactions such as hydroxylation, hydroxyl substitution, demethylation, decarboxylation/decarbonylation and ring opening, leading to the formation of nineteen oxidation products. The effective degradation by UV/PMS suggests a feasible technology for treating FLU in waters and wastewaters.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Shihui Yang, Baoyu Gao, Am Jang, Ho kyong Shon, Qinyan Yue〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Forward osmosis (FO) has been used in the wastewater treatment due to its advantages including low energy consumption and low membrane fouling. In this study, real municipal wastewater was concentrated by FO process using seawater concentrate as draw solution (DS). The influences of operating conditions such as temperature, flow velocity and sewage pre-filtration on water flux were investigated. Chemical oxygen demand, total nitrogen, ammonia nitrogen and total phosphorus could not be enriched by 4 times while sewage was reduced to 1/4 volume. Excitation and emission matrix fluorescence spectrum showed that a fraction of dissolved organic compounds in sewage transported across membrane into DS. Membrane fouling was evaluated by scanning electronic microscope analysis that a dense cake layer was formed on the membrane surface after sewage filtration. However, water flux of the fouled membrane was highly recovered after 1 h of physical cleaning.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Jingxin Yang, Zijun Dong, Chengchun Jiang, Chuan Wang, Hong Liu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Chemical oxidation processes have been extensively utilized in disinfection and removal of emerging organic contaminants in recent decades. Some undesired byproducts, however, are produced in these processes. Of them, bromate has attracted the most intensive attention. It was previously regarded as a byproduct that typically occurred in ozone-based oxidation processes. However, for the past decade, bromate formation has been detected in other oxidation processes such as CuO-catalyzed chlorination, SO〈sub〉4〈/sub〉〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/rad"〉〈sup〉-〈/sup〉-based oxidation, and ferrate oxidation processes. This review summarizes the occurrences, mechanisms, influencing factors, risk assessment, and control strategies of bromate formation in the four oxidation processes, i.e., ozone-based oxidation, chlorine-based oxidation, SO〈sub〉4〈/sub〉〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/rad"〉〈sup〉-〈/sup〉-based oxidation, and ferrate oxidation. Besides, some unresolved issues for future studies are provided: (1) Clarification of the relative contributions of SO〈sub〉4〈/sub〉〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/rad"〉〈sup〉-〈/sup〉 and Br〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/rad"〉 to the oxidation of bromine for bromate formation in SO〈sub〉4〈/sub〉〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/rad"〉〈sup〉-〈/sup〉-based oxidation processes; (2) evaluation of the role of different reactive species in the bromate formation in the process of UV/HOCl; (3) quantification of the dual role of alkalinity in bromate formation during ozonation; (4) assessment of the risks of bromate formation in SO〈sub〉4〈/sub〉〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/rad"〉〈sup〉-〈/sup〉-based oxidation processes for practical applications; and (5) exploration of strategies for inhibiting bromate formation in SO〈sub〉4〈/sub〉〈img src="https://sdfestaticassets-eu-west-1.sciencedirectassets.com/shared-assets/16/entities/rad"〉〈sup〉-〈/sup〉-based oxidation, UV/chlorine, and metal oxide-catalyzed chlorination processes.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S004565351931745X-egi1005JHC4BR7.jpg" width="373" alt="Image 100547" title="Image 100547"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Andrzej R. Reindl, Lucyna Falkowska, Agnieszka Grajewska〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Diet is the major route of exposure to environmental contaminants in biota and, after penetration into an organism, xenobiotics continue to accumulate in the body. In birds the egg-laying process acts as a transfer mechanism for the accumulated pollutants and results in the burdening of the next generation at an early stage of development. This transfer has a strong influence on developmental disorders and even breeding success. With this in mind polybrominated diphenyl ethers (PBDE), polychlorinated dibenzo-p-dioxins and polychlorinated dibenzo furans (PCDD/Fs), as well as polychlorinated biphenyls (PCBs), were analyzed in the eggs of aquatic birds from different habitats and with different diet preferences. The highest concentration of PBDE was noted in gull eggs (198.31 ng g〈sup〉−1〈/sup〉 dw.) and the lowest in tern eggs (sandwich tern: 76.96 ng g〈sup〉−1〈/sup〉 dw.; common tern: 113.73 ng g〈sup〉−1〈/sup〉 dw). Deca-BDE was detected only in herring gull eggs from the Wloclawek reservoir. PCDDF/s were found in the eggs of terns from the southern coast of the Baltic Sea and gulls from an inland reservoir (dam) on the River Vistula close to the town of Wloclawek. The highest toxicity (birds Toxic Equivalent Factor) was found in the eggs of terns (sandwich tern – 93.97 pg g〈sup〉−1〈/sup〉 dw., common tern – 68.35 pg g〈sup〉−1〈/sup〉 dw.), and this was found to be several times higher than in herring gull eggs (18.80 pg g〈sup〉−1〈/sup〉 dw.). Non-dioxin like PCBs were ten times higher than other analyzed PCB congeners, but the congener pattern was similar to other studies.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Jiaqing Xiong, Sihui Ren, Yifan He, Xiaochang C. Wang, Xuechen Bai, Jiaxuan Wang, Mawuli Dzakpasu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Nitrogen (N) and phosphorus (P) removal in conventional bioretention systems is highly variable. Therefore, five novel experimental columns with different media configurations and constituents, and incorporating a saturated zone were developed and assessed to optimize the removal of N, P and other nutrients. Three types of media composed of the conventional mixed sand and soil media (T〈sub〉1〈/sub〉), biochar-amended media (T〈sub〉2〈/sub〉), and iron-coated biochar (ICB)-amended media (T〈sub〉3〈/sub〉) were evaluated. Two of the experimental columns were designed with double-layer configurations, while the other three were of a single-layer structure. Removal efficiencies of nutrients in the experimental columns were evaluated and compared using simulated runoff. Also, the effect of media depth on the retention of P and denitrifying enzyme activity (DEA) in the bioretention columns were evaluated. The experimental column only filled with T〈sub〉3〈/sub〉 showed the best performance for COD, ammonia (NH〈sub〉4〈/sub〉〈sup〉+〈/sup〉-N) and total phosphorus (TP) removal (94.6%, 98.3% and 93.70%, respectively), whereas columns filled with T〈sub〉2〈/sub〉 performed poorly for TP removal (57.36%). For the removal of nitrate (NO〈sub〉3〈/sub〉〈sup〉−〈/sup〉-N) and total nitrogen (TN), the columns using a single-layer and only filled with either T〈sub〉3〈/sub〉 or T〈sub〉2〈/sub〉 exhibited the best performance (93% and 97% TN removal, respectively). Overall, this study demonstrates that our proposed single-layered bioretention cell only filled with T〈sub〉3〈/sub〉 and incorporating a saturated zone effectively improves the runoff quality, and can provide a new bioretention cell configuration for efficient stormwater treatment.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Xiao-He Liu, Zhong-Hang Xing, Qing-Yun Chen, Yun-Hai Wang〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉It is of significant importance to realize the efficient wastewater treatment and energy recovery. This study presents a multi-functional photocatalytic fuel cell (PFC), which could reductively treat Cr(VI) contaminant and oxidatively degrade organic pollutant simultaneously along with electricity production in an economical strategy. TiO〈sub〉2〈/sub〉 nanotube arrays (TNA) and graphite were used as photoanode and cathode in two separated chambers, respectively. The optimized PFC with open circuit voltage of 1.06 V, maximum power density of 1 W m〈sup〉−2〈/sup〉 and short circuit current density of 3.7 A m〈sup〉−2〈/sup〉 can be obtained by increasing Cr(VI) concentration and decreasing pH values in catholyte. Under optimized PFC conditions, more photogenerated electrons will be transferred to cathode for Cr(VI) reduction, and accelerating electron-hole separation in the photoanode, then facilitating the oxidation of organic pollutants on anode. More than 96.8% removal efficiency for 6.8 mM Cr(VI) with a cathodic efficiency of 95.1% can be achieved within 6 h. Methylene blue (MB), an organic model pollutant, is totally decolorized on photoanode, which is significantly improved compare to photocatalysis (61.5% removal efficiency). The stable cycle operation of this economical PFC has obtained owing to the stable and low cost materials of both photoanode and cathode. This work may provide an efficient and economical method to simultaneously remove two types of pollutants with electricity harvested in one cell.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519316819-fx1.jpg" width="256" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Kai Yang, Xuejun Jiang, Shuqun Cheng, LuLu Bai, Yinyin Xia, Chengzhi Chen, Pan Meng, Jing Wang, Chunlin Li, Qianghu Tang, Xianqing Cao, Baijie Tu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Benzo[a]pyrene (B[a]P) is a ubiquitous neurotoxic pollutant that widely distributes in the natural environment. However, the exact mechanism of B[a]P-induced neurotoxicity has not been well established. As one key synaptic protein, SNAP-25 plays an important role in the regulation of neurotransmitter release, including synaptic dopamine release. In this study, we demonstrated that, after intragastric administration of B[a]P in rats aged postnatal day 5 for 7 weeks, B[a]P significantly increased the level of dopamine and the expression of SNAP-25, dopamine receptor 1 (DRD1) and DRD 3. Moreover, treatment of B[a]P also caused the ultra-structural pathological changes in the cerebral cortex of rats. To further reveal the potential role of SNAP-25 in the regulation of DRDs, we treated the dopaminergic PC-12 cells with 20 μM B[a]P for 24 h. A significant cytotoxicity and apoptosis were observed, and more importantly, we found that SNAP-25, DRD 1 and DRD 3 co-localized in the cells, and down-regulation of SNAP-25 by CRISPR-Cas9 plasmid remarkably reduced the expression of DRD1 and DRD3. Together, our findings suggest that, synaptic dopamine release may be positively regulated by SNAP-25 via its receptors, and thus affecting the neurotoxicity induced by B[a]P.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519315991-egi10GW826ST6K.jpg" width="380" alt="Image 108266" title="Image 108266"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): María I. Troncozo, Marija Lješević, Vladimir P. Beškoski, Boban Anđelković, Pedro A. Balatti, Mario C.N. Saparrat〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Grape pomace (GP) from 〈em〉Vitis labrusca〈/em〉, the main byproduct from “American table wine” production, is recalcitrant to degradation, and its accumulation is a serious problem with negative environmental impacts. In this work, transformation of grape pomace using a steam pretreatment followed by incubation of GP during a 90-day period with six different fungi were evaluated. Several fungi tested reduced the phytotoxicity of water-soluble fraction (WSF〈sub〉d〈/sub〉) from steam-pretreated GP after 90 days’ incubation to lettuce and tomato seeds. 〈em〉U. botrytis〈/em〉 caused the largest effective phytotoxicity reduction of WSF〈sub〉d〈/sub〉 (used in the concentration range of 10–1.25% p/v) and was the only fungus causing the removal of monoaromatic compounds. Therefore, this procedure with 〈em〉U. botrytis〈/em〉 effectively reduces the availability of phytotoxic monoaromatic compounds in GP, which opens a way for the development of guidelines for the management of these wastes and their potential use as organic amendments in agricultural soil.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Manli Wu, Jialuo Wu, Xiaohui Zhang, Xiqiong Ye〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This study assessed the benefits of biostimulation with nitrogen and phosphorous (BS) versus bioaugmentation with native petroleum degrading flora (BA) in terms of petroleum hydrocarbon removal and microbial community structure shift in petroleum-polluted loessal soil. After 12 weeks of remediation, the TPH degradation efficiencies were 28.3% and 13.9% in BS and BA treated soils, respectively. Biostimulation was more effective than bioaugmentation for petroleum hydrocarbon degradation. Soil microbial community composition changed while microbial diversity decreased greatly by bioaugmentation treatment. The inoculum could survive, grow up quickly and become the predominant microorganisms after one week of inoculation. In the biostimulation treatment, microbial community composition is more evenness and richness than in the bioaugmented remediation. The strong positive correlations of the nitrogen and phosphorus with the petroleum hydrocarbon suggest the importance of nutrients for petroleum biodegradation in the contaminated loessal soil. The results indicate that the stabilization and variety of the microbial community structure are essential for the petroleum biodegradation performance. Further engineering is suggested to improve the evenness and richness of the soil microbial community since an abundance of nitrogen and phosphorus nutrients ensures the degraders’ activity in the petroleum polluted soil.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Donghwi Kim, Jee-Hyun Jung, Sung Yong Ha, Joon Geon An, Ravi Shankar, Jung-Hwan Kwon, Un Hyuk Yim, Sung Hwan Kim〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this study, developmental toxicity was increased as the oil was further degraded under natural sunlight. Detailed chemical composition of the degraded oils was examined by use of gas chromatography (GC) and (−) electrospray ionization ultrahigh resolution mass spectrometry (UHR-MS). Baseline toxicities were estimated based on chemical activities of polycyclic aromatic hydrocarbons, and it was obvious that the predicted chemical activities can not explain increased toxicity alone. However, the ultrahigh resolution mass spectral abundance of polar compounds including O〈sub〉3〈/sub〉 and O〈sub〉4〈/sub〉 class compounds was significantly increased as the photodegradation proceeded. Further examination of double bond equivalence values of the compounds showed that polar compounds with both non-aromatic and aromatic polar structures were increased. Statistical analysis indicates that the increased toxicity can be well explained by the increased polar compounds. Therefore, the oxygenated compounds identified in this study can play an important role in toxicity of degraded oils.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519315644-fx1.jpg" width="315" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Wojciech Smułek, Zefiryn Cybulski, Urszula Guzik, Teofil Jesionowski, Ewa Kaczorek〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Pollution of the environment with chlorinated aromatic compounds is a problem of increasing importance, which has stimulated the search for efficient methods for the remediation of contaminated soil and water. Additionally, for better understanding of the significance of bioavailability to biodegradation, investigation of the cell surface properties is necessary. Hence, this study concerns the properties and possible application, in chlorotoluene removal, of three newly isolated environmental bacterial strains from the genera 〈em〉Pseudomonas〈/em〉, 〈em〉Raoultella〈/em〉 and 〈em〉Rahnella〈/em〉. The results show the differences in the biochemical profiles of the isolated strains, their cellular fatty acid composition and their hemolytic properties. However, all three strains exhibit high biodegradation potential, degrading not less than 60% of each monochlorotoluene isomer in 21-day experiments. What is more, observations of changes in the cell surface properties indicate the possible adaptation mechanisms of the strains that enable efficient biodegradation of hydrophobic pollutants such as monochlorotoluenes.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519316765-fx1.jpg" width="500" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Huan Yu, Wei Hu, Jun He, Zhaolian Ye〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Dielectric barrier discharge (DBD) has been widely used as end-of-pipe technology to degrade low-concentration volatile organic compound (VOC) emissions. In this work, the influence of DBD conditions including discharge voltage, VOC residence time in DBD plasma, VOC initial concentration and synergistic effect of multiple VOC mixing on the decomposition efficiency of three VOCs (toluene, ethyl acetate and acetone) were investigated systematically. One focus of this work was to investigate size distribution and chemical composition of aerosol by-products. The results suggested that high discharge voltage, long residence time and low VOC initial concentration would increase VOC removal ratio and their conversion to CO〈sub〉2〈/sub〉. Among the three VOCs, toluene was easiest to form particles with a mode diameter between 40 and 100 nm and most difficult to be decomposed completely to CO〈sub〉2〈/sub〉. Maximum aerosol yield from toluene was observed to account for 13.1 ± 1.0% of initial concentration (400 ppm) in the condition of discharge voltage 6 kV and residence time 0.52 s. Gas chromatography-mass spectrometry analysis showed that non-nitrogen containing benzene derivatives, nitrophenol derivatives and amines were the main components of toluene aerosol by-products. For ethyl acetate and acetone, aerosols could only be produced in the condition of high discharge voltages (〉7.5 kV) and long gas residence time (≥0.95 s) with a bimodal distribution below 20 nm. When the mixture of three VOCs was fed into the plasma, we observed a strong synergistic effect that led to higher VOC removal ratio, but lower conversion of decomposed VOCs to CO〈sub〉2〈/sub〉 and aerosols.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Valdeir Celestino dos Santos Junior, Luis Carlos Martínez, Angelica Plata-Rueda, Flávio Lemes Fernandes, Wagner de Souza Tavares, José Cola Zanuncio, José Eduardo Serrão〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Broad-spectrum insecticides used in pest control are a risk for non-target insects. Their compatibility to the insecticide spinosad, used in agriculture and forestry as a biological control tool, needs to be evaluated. 〈em〉Podisus nigrispinus〈/em〉 Dallas (Heteroptera: Pentatomidae) is a predatory bug used in the pest management of agricultural and forest systems where spinosad is also frequently applied. The aim of this study was to evaluate the toxicity, histopathology and cytotoxicity in midgut cells of 〈em〉P. nigrispinus〈/em〉 exposed to spinosad. The toxicity test was performed to determine the lethal concentrations of spinosad after exposure by ingestion. The histopathology and cytotoxicity caused by spinosad were analyzed in the three midgut regions (anterior, middle and posterior) of 〈em〉P. nigrispinus〈/em〉 during different exposure periods. Spinosad, at low concentrations, was toxic to 〈em〉P. nigrispinus〈/em〉 [LC〈sub〉50〈/sub〉 = 3.15 (3.02–3.26) μg.L〈sup〉−1〈/sup〉]. Cell degeneration features such as cytoplasm vacuolization, chromatin condensation and release of cell fragments to the midgut lumen were observed in this organ. Cell death via apoptosis was found in the three midgut regions of this predator after exposure to the insecticide. Spinosad is toxic to 〈em〉P. nigrispinus〈/em〉, and causes histological and cytological damage followed by cell death in the midgut, suggesting a dangerous effect on a beneficial non-target insect.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Supaporn Phanwilai, Suratchana Piyavorasakul, Pongsak (Lek) Noophan, Kevin D. Daniels, Shane A. Snyder〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Inhibition of anammox activities was tested with two ranges of chloramphenicol (CAP) concentration (5, 10, 20, 50, and 100 mg L〈sup〉−1〈/sup〉) and (100, 500, and 1000 μg L〈sup〉−1〈/sup〉). In a short-term study, strong inhibition of activity was dependent of CAP concentration in both attached-growth (SBR-A) and suspended-growth (SBR-S) systems. The activities of attached-growth cultures at all CAP concentrations were reversible after 1 day, while activities for suspended-growth cultures were only gradually reversible dependent on the CAP concentrations. In long-term studies with daily additions of 6 mg L〈sup〉−1〈/sup〉 CAP, the anammox activity on day 41 in SBR-A had decreased to 18% baseline (SAA reduced from 0.528 to 0.096 mg N mg〈sup〉−1〈/sup〉 VSS d〈sup〉−1〈/sup〉). More rapid reduction of anammox activity was observed in SBR-S, down to 17% baseline after only 27 days (SAA decreased from 0.576 to 0.096 mg N mg〈sup〉−1〈/sup〉 VSS d〈sup〉−1〈/sup〉). Inhibition was irreversible in both SBR-S and SBR-A after the long-term study. With lower CAP additions (100–1000 μg L〈sup〉−1〈/sup〉), the activities in both reactors were stable during daily CAP addition for two weeks. Attached-growth cultures tended to be more tolerant of CAP addition than suspended-growth cultures. Both un-competitive and non-competitive models could be used to compare anammox activities with the higher CAP concentrations. The SAA〈sub〉max〈/sub〉 [fx] (the maximum specific anammox activity) and 〈sub〉h〈/sub〉 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.svg"〉〈mrow〉〈msub〉〈mrow〉〈mi〉K〈/mi〉〈/mrow〉〈mrow〉〈mi〉i〈/mi〉〈/mrow〉〈/msub〉〈/mrow〉〈/math〉 (the inhibition constant) of SBR-A were 0.48 mg N mg〈sup〉−1〈/sup〉 VSS d〈sup〉−1〈/sup〉 and 98.3 mg L〈sup〉−1〈/sup〉, respectively. The SAA〈sub〉max〈/sub〉[fx] and 〈math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si1.svg"〉〈mrow〉〈msub〉〈mrow〉〈mi〉K〈/mi〉〈/mrow〉〈mrow〉〈mi〉i〈/mi〉〈/mrow〉〈/msub〉〈/mrow〉〈/math〉 of SBR-S were 1.25 mg N mg〈sup〉−1〈/sup〉 VSS d〈sup〉−1〈/sup〉and 71.1 mg L〈sup〉−1〈/sup〉, respectively.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Chengbin Xu, Yongmei Fan, Xiaokai Zhang, Weihao Kong, Weiguo Miao, Qing X. Li〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Cyantraniliprole can effectively control lepidopteran pests and has been used all over the world. In general, the risk of cyantraniliprole seems low for fish, but the toxicity selectivity among different fish species was not clear. Here the acute toxicity and chronic effects of cyantraniliprole to juvenile tilapia (〈em〉Oreochromis mossambicus〈/em〉) were assessed. The results showed that 96 h LC〈sub〉50〈/sub〉 of cyantraniliprole to tilapia was 38.0 mg/L. After exposed for 28 days, specific growth rates of the blank control, solution control, and the treatments of 0.037, 0.37 and 3.7 mg/L of cyantraniliprole were 1.14, 0.95, 0.93, 0.82 and 0.70% per day, respectively. The results of micronucleus experiment and single cell gel electrophoresis showed that cyantraniliprole damaged DNA in liver cells of tilapia larvae. Quantitative PCR results showed that cyantraniliprole could induce the up-regulation of 〈em〉Rpa〈/em〉 3 that is responsible for the DNA repair. The significantly down-regulation of 〈em〉Chk 2〈/em〉 gene was related to p53 pathway. It is therefore proposed that cyantraniliprole causes DNA damage in liver cells of tilapia and activates DNA damage and repair pathways.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Fan Si, Yongqing Zhang, Chenhui Yao, Meimei Du, Imtyaz Hussain, Shaobin Huang, William Wen, Xijun Hu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Nitroimidazoles are found in pharmaceuticals and personal care products (PPCPs) and, when discharged into the environment, have adverse effects on human health and survival. Advanced oxidation technologies (AOTs) based on persulfate (PS) can rapidly and efficiently degrade organic pollutants via strong oxidizing radicals under activation conditions. This study investigated the degradation of ronidazole (RNZ) by indirect electrolytic generation of PS and its activator, ferrous ion (Fe〈sup〉2+〈/sup〉). An electrochemical system was developed, with a high concentration of PS generated at the anode while the activator Fe〈sup〉2+〈/sup〉 was produced at the cathode. It showed that ammonium polyphosphate (APP) could effectively promote the electrolysis of PS. A high current efficiency (88%) at the anode could be obtained after 180 min at a high current density (300 mA cm〈sup〉−2〈/sup〉). However, Fe〈sup〉2+〈/sup〉 was inhibited at the cathode due to material control. The degradation of RNZ in the Fe〈sup〉2+〈/sup〉/PS system generated from the electrochemical system was also explored. Increasing PS concentration and Fe〈sup〉2+〈/sup〉/PS ratio were beneficial to the RNZ degradation. In homogeneous reactions, the degradation efficiency of RNZ could be improved by decreasing the Fe〈sup〉2+〈/sup〉 addition rate through a peristaltic pump. Five intermediates were also detected and the degradation pathways were proposed. These findings provide a new method and mechanism for rapid and efficient degradation of RNZ.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S004565351931803X-fx1.jpg" width="455" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Javier Bayo, Sonia Olmos, Joaquín López-Castellanos〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This paper presents the abundance, concentration and variability of microplastics (MP) in an urban wastewater treatment plant (WWTP), according to different water parameters and environmental factors, their possible sources and removal efficiency. A total of 352.6 L of wastewater from four stages of the treatment process were processed following a standardized extraction protocol by density separation, trinocular microscopic identification and polymeric analysis by Fourier transform infrared spectroscopy. MP comprised a 46.6% of total microlitter, with a statistically significant removal of 90.3% in the final effluent of the WWTP. Five different shapes were isolated; i.e. fragment, film, bead, fiber, and foam. The most prominent MP forms in the final effluent were fragments and fibers, with the most common size class being 400–600 μm. Seventeen different polymer families were identified, with low-density polyethylene being the most prevalent one (52.4%) in a film form (27.7%), mostly from agriculture greenhouses near the sewage plant and single plastic bags (it is noted that only a year ago consumers are charged for them in Spain). Influent wastewater with high concentrations of suspended solids proved to have a low MP burden with a larger MP size, possibly due to a hetero-aggregation with particulate matter. Agglomeration of polystyrene and polyethylene terephthalate with organic material is also suggested, both with surface energies higher than 25 mN m〈sup〉−1〈/sup〉 enough for a high biofouling rate. The sewage plant cushions sharp-point microplastic concentrations during the warm season, allowing a stable performance of the WWTP.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S004565351931817X-fx1.jpg" width="448" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: Available online 17 August 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere〈/p〉 〈p〉Author(s): Hong-wei Wang, Shi-quan Zhu, Jing Liu, Cheng-yi Miao, Yan Zhang, Bian-hua Zhou〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A fluoride exposure mouse model is established to evaluate the relationship between mitochondrial respiratory chain complexes and renal dysfunction. Morphological changes in kidney tissues were observed. Renal function and cell proliferation in the kidneys were evaluated. The expression of mitochondrial fusion protein including mitofusin-1 (Mfn1) and optic atrophy 1 (OPA1), and mitochondrial respiratory chain complex subunits, including NDUFV2, SDHA, CYC1 and COX Ⅳ, were detected via real-time polymerase chain reaction, immunohistochemistry staining and Western blot, respectively. Results showed that the structures of renal tubule, renal glomerulus and renal papilla were seriously damaged. Renal function was impaired, and cell proliferation was remarkably inhibited by excessive fluoride in kidney. The mRNA and protein expression levels of Mfn1, OPA1, NDUFV2, CYC1 and COX Ⅳ were significantly increased after excessive fluoride exposure. However, the mRNA and protein expression of SDHA significantly decreased. Overall, our findings revealed that excessive fluoride can damage kidney structure, inhibit renal cell proliferation, interfere with the expression of mitochondrial respiratory chain complexes and elevate mitochondrial fusion. Consequently, renal function disorder occurred.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Lisa Baumann, Henrik Holbech, Heike Schmidt-Posthaus, Angela P. Moissl, Mark Hennies, Janina Tiedemann, Lennart Weltje, Helmut Segner, Thomas Braunbeck〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Vitellogenin (VTG), a well-established biomarker for the diagnosis of endocrine activity in fish, is used in multiple OECD test guidelines (TG) to identify activities of chemicals on hormonal pathways. However, the synthesis of VTG may not only be modified by typical endocrine-related pathways, but also through non-endocrine-mediated processes. In particular, hepatotoxicity, i.e. toxicant-induced impairment of liver structure and function, might influence VTG as a biomarker, since VTG is synthesized in hepatocytes. An intimate understanding of the interplay between endocrine-related and non-endocrine-related pathways influencing VTG production is crucial for the avoidance of erroneous diagnoses in hazard assessment for regulatory purposes of chemical compounds. In order to investigate whether hepatotoxicity may interfere with hepatic VTG synthesis, adult zebrafish (〈em〉Danio rerio〈/em〉) were exposed to three well-known hepatotoxicants, acetaminophen, isoniazid and acetylsalicylic acid, according to OECD TG 230. Various hepatotoxicity- and endocrine system-related endpoints were recorded: mRNA expression of selected endocrine- and hepatotoxicity-related marker genes in the liver; VTG levels in head/tail homogenates; and liver histopathology. All three test compounds induced significant, but mild single cell necrosis of hepatocytes and transcriptional changes of hepatotoxicity-related marker genes, thus confirming hepatotoxic effects. A positive correlation between hepatotoxicity and reduced hepatic VTG synthesis was not observed, with the single exception of a weak increase in female zebrafish exposed to APAP. This suggests that – in studies conducted according to OECD TG 229 or 230 − it is unlikely that hepatotoxic chemicals will interfere with the hepatic capacity for VTG synthesis.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Tsair-Fuh Lin, Veeriah Jegatheesan, Li Shu, Eldon Raj Rene〈/p〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Ikrema A. Hassan, Eltayeb E. Mohamedelhassan, Ernest K. Yanful, Brian Weselowski, Ze-Chun Yuan〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This study investigated the isolation and characterization of three novel bacterial strains; 〈em〉Acinetobacter calcoaceticus〈/em〉, 〈em〉Sphingobacterium multivorum〈/em〉, and 〈em〉Sinorhizobium〈/em〉, isolated form agriculture land. From three hundred strains of bacteria, the three isolates were identified for their superior diesel degradation ability by a series of bench-scale tests. The isolates were further investigated in bench tests for their ability to grow in different diesel fuel concentrations, temperature and pH; degrade diesel fuel 〈em〉in vitro;〈/em〉 and for the identification of functional genes. Semi-pilot bioelectrokinetic tests were conducted in three electrokinetic cells. An innovative electrode configuration was adopted to stabilize the soil pH and water content during the test. The genes expressed in the diesel degradation process including Lipases enzymes Lip A, LipB, Alk-b2, rubA, P450, and 1698/2041 were detected in the three isolates. The results showed that the solar panel voltage output is in agreement with the trapezoid model. The temperatures in the cells were found to be 5–7 °C higher than the ambient temperature. The electrode configuration succeeded in stabilizing the soil pH and water content, preventing the development of a pH gradient, important progress for the survival of bacteria. The diesel degradation in the soil after bioelectrokinetic tests were 20–30%, compared to 10–12% in the controls. The study succeeded in developing environmentally friendly technology employing novel bacterial strains to degrade diesel fuel and utilizing solar panels to produce renewable energy for bioelectrokinetics during the winter season.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Shivani, Ranu Gadi, Sudhir Kumar Sharma, Tuhin Kumar Mandal〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Deteriorating air quality with high levels of fine particulate matter (PM〈sub〉2.5〈/sub〉) over National Capital Region (NCR) of India is one of the serious environmental and scientific issues. In this paper, PM〈sub〉2.5〈/sub〉 samples were collected for 24 h twice or thrice a week during December 2016–December 2017 at three sites [Delhi (IG), Modinagar (MN) and Mahendragarh (HR)] over NCR to analyse the carbonaceous aerosols. Source apportionment of PM〈sub〉2.5〈/sub〉 was attempted using Principal Component analysis (PCA) and Positive Matrix Factorization (PMF) based on the analysed carbonaceous fractions [Organic carbon, Elemental carbon, Secondary organic carbon (SOC)]. Organic compounds: alkanes, hopanes, steranes, polycyclic aromatic hydrocarbons (PAHs), phthalates, levoglucosan and n-alkanoic acids were analysed to distinguish the emission sources. Total Carbonaceous Aerosols (TCA) contributed significantly (∼26%) to PM〈sub〉2.5〈/sub〉 which revealed their importance in source apportionment. Estimated SOC contributed 43.2%, 42.2% and 58.2% to OC and 5.4%, 5.3% and 7.8% to PM〈sub〉2.5〈/sub〉 at IG, MN and HR sites respectively. PCA and PMF apportion five emission sources i.e., vehicular emissions (34.6%), biomass burning (26.8%), cooking emissions (15.7%), plastic and waste burning (13.5%) and secondary organic carbon (9.5%) for PM〈sub〉2.5〈/sub〉. Source attributed health risk has also been calculated in terms of Lung cancer risk (LCR) associated with PAHs exposure and concluded that vehicular emissions (40.3%), biomass burning (38.1%), secondary organic carbon (12.8%) contributed higher to LCR (503.2 × 10〈sup〉−5〈/sup〉; ∼503 cases in 1,00,000). Health risk assessment combined with source apportionment inferences signifies the immediate implementation of emissions reduction strategies with special target on transport sector and biomass burning over the NCR of India.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Prasit Shrestha, Boris Meisterjahn, Christopher B. Hughes, Philipp Mayer, Heidi Birch, Dieter Hennecke〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Degradation data are crucial for the persistence assessment of chemicals and they are generated using standard OECD guidelines. The OECD 308 describes a simulation biodegradation test of chemicals in water-sediment systems. This guideline is not applicable for testing highly volatile chemicals and recommends a closed biometer test setup for testing slightly volatile chemicals. However, proper details on system geometries, construction and monitoring of aerobic conditions are not provided. The choice of system geometry and sediment:water ratio influences the partitioning of test chemicals between different compartments (water, sediment and headspace) and can therefore affect their degradation. The guideline recommends the addition of test chemical via aqueous solutions, which however is not possible for hydrophobic volatile chemicals due to their volatilization losses and low solubility. Thus, the use of a co-solvent is necessary for the application of such chemicals but its effects in a closed setup has not been studied. We recently developed an improved closed test setup for testing volatile chemicals in soil. The objective was to adapt this improved test setup to conduct OECD 308 tests using 〈sup〉14〈/sup〉C labelled chemicals with different volatilities. Using the adapted test setup it was possible to obtain a complete mass balance even for n-decane and tetralin having the highest Henry's constants of the tested chemicals. However, the use of co-solvent affected the oxygen levels, which in turn affected microbial activity and likely also the degradation of test chemicals. Therefore, the adapted test setup needs further developments for the testing of volatile hydrophobic chemicals.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519317400-fx1.jpg" width="353" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: January 2020〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 238〈/p〉 〈p〉Author(s): Jara Hurtado-Gallego, Gerardo Pulido-Reyes, Miguel González-Pleiter, Gorka Salas, Francisco Leganés, Roberto Rosal, Francisca Fernández-Piñas〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉Superparamagnetic iron oxide nanoparticles (SPION) have been widely studied for different biomedical and environmental applications. In this study we evaluated the toxicity and potential alterations of relevant physiological parameters caused to the microalga 〈em〉Chlamydomonas reinhardtii〈/em〉 (〈em〉C. reinhardtii〈/em〉) upon exposure to SPION. The results showed dose-dependent toxicity. A mechanistic study combining flow cytometry and physiological endpoints showed a toxic response consisting of a decrease in metabolic activity, increased oxidative stress and alterations in the mitochondrial membrane potential. Additionally, and due to the light absorption of SPION suspensions, we observed a significant shading effect, causing a marked decrease in photosynthetic activity. In this work, we demonstrated for the first time, the internalization of SPION by endocytosis in 〈em〉C. reinhardtii〈/em〉. These results demonstrated that SPION pose a potential risk for the environment if not managed properly.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519317862-fx1.jpg" width="282" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Amal Abdelhaleem, Wei Chu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A hybrid process was proposed for carbofuran (CBF) degradation, a carbamate pesticide with a special refractory property, through peroxymonosulfate (PMS) activation under visible LED (Vis LED) by Fe〈sup〉III〈/sup〉 impregnated N-doped TiO〈sub〉2〈/sub〉 photocatalyst (FeNT). An in-depth investigation was conducted to examine the synergistic effect of the FeNT/PMS/Vis LED process under various reaction conditions. An increase in the rate constant was observed with the increment of pH from 2.4 to 7.4, implying the feasibility of the process at neutral pH. A further increase in pH from 8.9 to 11 showed a sudden drop in the rate constant (if the role of base activation is ignored). The efficiency of CBF degradation is still more than 70% after adding NO〈sub〉3〈/sub〉〈sup〉−〈/sup〉, SO〈sub〉4〈/sub〉〈sup〉2−〈/sup〉, HCO〈sub〉3〈/sub〉〈sup〉−〈/sup〉, and Cl〈sup〉−〈/sup〉. Interestingly, the efficiency was not influenced even after the further increment of nitrate concentration. Furthermore, the high chloride concentrations caused an enhanced efficiency due to the generation of reactive halogens through two-electron transfer. Sixteen major intermediates were recognized and eight of them were never reported in the previous studies. Surprisingly, a new degradation pathway was noted in this study via H-abstractions and cyclization mechanisms. The FeNT/PMS/Vis LED process exhibited a dual functionality in terms of mineralization efficiency and about 90% TOC reduction can be achieved. Therefore, these findings provide new insights into the mechanism of PMS activation under Vis LED after coupling non-metal doped TiO〈sub〉2〈/sub〉 photocatalyst with a metal component, and its implications for degradation of refractory and non-biodegradable pollutants in wastewater.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Jerzy Falandysz, Alwyn Fernandes, Martin Rose〈/p〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Patryk Oleszczuk, Bożena Czech, Magdalena Kończak, Aleksandra Bogusz, Anna Siatecka, Paulina Godlewska, Mark Wiesner〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The effect of zinc oxide nanoparticles (ZnO NPs) and zinc sulfide nanoparticles (ZnS NPs) on the toxicity of sewage sludges in sewage sludge-amended soils was investigated with respect to plant- (〈em〉Lepidium sativum〈/em〉) and soil- (〈em〉Folsomia candida〈/em〉) species. The toxicity of porewater obtained from the tested soils towards 〈em〉Vibrio fischeri〈/em〉 (Microtox®) was also investigated. Two sewage sludges (SSL1 and SSL2) with different organic matter content were amended with nanoparticles. Depending on the type of biotest and the type of sewage sludge, different effects of ZnO or ZnS NPs on the toxicity of sewage sludge-amended soil were observed. In general, ZnO and ZnS NPs stimulated root growth for SSL1 or reduced the harmful impact of SSL2 on the root growth of 〈em〉L. sativum〈/em〉 roots. Greater stimulation or inhibition of root growth was observed for the ZnO than ZnS NPs. The unfavorable effect of ZnO/ZnS NPs on 〈em〉F. candida〈/em〉 mortality and reproduction was observed at a concentration of ZnO/ZnS in sewage sludge ≥250 mg/kg. Generally, there were no significant differences between ZnO and ZnS NPs toxicity towards 〈em〉F. candida〈/em〉. Aging for 45 days of sewage sludge-amended soil containing NPs affected ZnO and ZnS NPs toxicity to all tested organisms. In the most cases, the toxicity decreased after 45 days of aging for plant (〈em〉L. sativum〈/em〉) and invertebrates (〈em〉F. candida〈/em〉). The toxicity of porewater to 〈em〉V. fischeri〈/em〉 from sewage sludge-amended soil contains ZnO NPs did not change, while in the case of ZnS NPs, the toxicity increased after 45 days of aging.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Soma Ghosh, Sohini Majumder, Tarit Roychowdhury〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉〈em〉Adi Ganga,〈/em〉 an open canal in Kolkata, constitutes a dump to a large part of the urban wastes produced. The constant and uncontrolled disposal of the wastes contributes to the degradation of water quality of 〈em〉Adi Ganga〈/em〉, which in turn might have adverse effect on groundwater in the adjoining areas. Surface water (SW) and groundwater (GW) collected from six locations along 〈em〉Adi Ganga〈/em〉 were analyzed to understand the extent of degradation caused due to SW pollution. Among the important water quality parameters and heavy metal analysis - dissolved oxygen, turbidity, total hardness, alkalinity, biological oxygen demand, oil and grease and zinc of both SW and GW were found to be much greater than their respective permissible limits (WHO, 2004). Both the SW and GW samples depicted phosphate and bicarbonate beyond their recommended values whereas; cations were well within the limit. Hydrochemical analysis through Piper, Stiff, Stabler, Schoeller-Berkaloff and Wilcox diagrams indicate that the water is dominated by calcic and magnesian facies with chlorinated and bicarbonate water types with higher alkalinity. Average water quality index of 33.7 and 52.4 for SW and GW indicate that these are severely and marginally threatened, respectively. Cluster analysis and Pearson's correlation studies show similar trend for both SW and GW indicating role of SW pollution in quality degradation of GW. The SW quality parameters found beyond permissible limits are mainly contributed anthropogenically therefore, immediate stoppage of further pollution of SW is imperative to stop degradation of GW quality, a regular and reliable source of drinking water.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S004565351931731X-fx1.jpg" width="352" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Farzaneh Mohammadi, Mohammad Reza Samaei, Abooalfazl Azhdarpoor, Hakimeh Teiri, Ahmad Badeenezhad, Saeid Rostami〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This study aimed to model and optimize pyrene removal from the soil contaminated by sorghum bicolor plant using Response Surface Methodology (〈em〉RSM〈/em〉) and Artificial Neural Network (〈em〉ANN〈/em〉) with Genetic Algorithm (〈em〉GA〈/em〉) approach. Here, the effects of indole acetic acid (IAA) and pseudomonas aeruginosa bacteria on increasing pyrene removal efficiency by phytoremediation process was studied. The experimental design was done using the Box-Behnken Design (〈em〉BBD〈/em〉) technique. In the 〈em〉RSM〈/em〉 model, the non-linear second-order model was in good agreement with the laboratory results. A two-layer Feed-Forward Back-Propagation Neural Network (〈em〉FFBPNN〈/em〉) model was designed. Various training algorithms were evaluated and the Levenberg Marquardt (〈em〉LM〈/em〉) algorithm was selected as the best one. Existence of eight neurons in the hidden layer leads to the highest R and lowest MSE and MAE. The results of the GA determined the optimum performance conditions. The results showed that using indole acetic acid and pseudomonas bacteria increased the efficiency of the sorghum plant in removing pyrene from the soil. The comparison obviously indicated that the prediction capability of the ANN model was much better than that of the RSM model.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Yujia Xiang, Zhangyi Xu, Yaoyu Zhou, Yuyi Wei, Xingyu Long, Yangzhou He, Dan Zhi, Jian Yang, Lin Luo〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉This present study reported the synthesis and characterization of a low-cost, environment friendly and high efficient biochar, ferromanganese modified biochar (Fe/Mn-BC) for the removal of levofloxacin (LEV) from aqueous medium. Fe/Mn-BC was synthesized through the facile co-precipitation of Fe, Mn with vinasse wastes and then pyrolysis under controlled conditions. The characterization of Fe/MnBC was analyzed by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction patterns (XPS), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and Raman. Some influencing factors (e.g., pH, Fe/Mn-BC dosage, initial LEV concentration, ionic strength, contact time and temperature) were comprehensively investigated. The results manifested that the adsorption process of LEV onto Fe/Mn-BC was high pH dependence and the maximum adsorption capacity was achieved at pH 5. Moreover, the adsorption capacity of LEV was increased with increasing ionic strength. To gain a clearer perspective on the adsorption behavior of LEV onto Fe/Mn-BC, the adsorption kinetics and isotherms were also performed, revealing pseudo-second-order and Freundlich model had a better fitting effect. Reusability experiments indicated that Fe/Mn-BC could maintain a certain adsorption capacity for LEV after 5 recycles. Overall, this work showed that Fe/Mn-BC was an effective and promising adsorbent for eliminating LEV from aqueous medium.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Danni Zhang, Shaofeng Wang, Mario A. Gomez, Ying Wang, Yongfeng Jia〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The coprecipitation of arsenic with Fe(III) by lime neutralization is widely used in industrial practices to treat arsenic-containing waste waters generated from mineral processing operations. In this work, coprecipitation was conducted directly at pH 8 to simulate the operations in hydrometallurgical practices, which differed from the conventional laboratory operations. Moreover, although ferric is the major species of iron in arsenic-containing waste waters, the coexistence of ferrous ions cannot be ignored. Therefore, the effect of different neutralization modes, as well as the effect of ferrous ions on the removal of arsenic and the stability of the generated arsenic-bearing wastes, was systematically investigated. The result showed that arsenic was still released back into the liquid phase under alkaline conditions even for the samples formed directly at alkaline pH. It was found that the extra addition of Fe(II) may exert negative effect on the stability of the as-formed Fe(II)–Fe(III)–As(V) coprecipitates at pH 7 − 10. The concentration of ferrous ions in the liquid/solid phase decreased with increasing pH for each sample formed at different Fe(II)/Fe(tot). The results indicated that complete oxidation of the ferrous ions before coprecipitation with arsenic should be conducted to achieve optimal stability of the arsenic-bearing wastes for hydrometallurgical practice and waste disposal.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Rafia Shaikh, Tasneem Gul Kazi, Hassan Imran Afridi, Asma Akhtar, Jameel Ahmed Baig〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉A novel ionic liquid-based vortex assisted dispersive liquid–liquid micro extraction procedure(IL-VADLLμE) was proposed for the enrichment of toxic metals, cadmium (Cd) and lead (Pb) in different types of water samples, domestic treated and groundwater (tube well and hand pump). Whereas, the concentration of both toxic metals was also determined in the scalp hair of children (age ranged 1–3 years), drinking contaminated groundwater termed as exposed group, whereas for comparative purposes scalp hair of age matched children consumed domestically treated water, named as non-exposed group. To preconcentrate the trace levels of Cd and Pb, a green chelating agent, 〈span〉l〈/span〉-cysteine (2-amino-3-sulfhydrylpropanoic acid) was used for complexation, an ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate [BMIM] [PF〈sub〉6〈/sub〉] utilized as extractant and hexafluorophosphate ion (PF〈sub〉6〈/sub〉〈sup〉−〈/sup〉) as anion pairing agent, which facilitate the enrichment of hydrophobic complexes of analytes into the acceptor phase. Various operative features for the IL-VADLLμE method like pH of standards/samples, volume of ionic liquid and sample solution, concentration of ligand, ion pair reagent and ionic liquid, vortex and electrical shaking time (for comparative purpose), were thoroughly optimized. The projected method was effectively applicable to assess the Cd and Pb in trace level in real water sample (surface and groundwater) and scalp hair samples of children belongs to exposed and non-exposed areas. The high contents of both toxic metals in scalp hair samples of children consuming groundwater indicate that the adverse impacts of both toxic metals especially Pb on the general health as well as neuron and skeletal problem, from child hood.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519316650-fx1.jpg" width="288" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Sabina Ziembowicz, Małgorzata Kida, Piotr Koszelnik〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The work detailed here investigated the efficiency of oxidising technologies in clearing aqueous solutions of di-〈em〉n〈/em〉-butyl phthalate (DBP), a known endocrine-disrupting compound (EDCs). Specifically, this paper addresses the use of the classic Fenton process, and the development of a modification of Fenton's reagent targeted at the degradation of di-〈em〉n〈/em〉-butyl phthalate in aqueous solution. The modification in question entailed the use of alternative catalysts or a mixture thereof. Hence oxidation by hydrogen peroxide (at various different concentrations), the classic Fenton process, was tested for the removal of DBP, alongside versions modified in terms of the quantitative and qualitative composition of a mixture of catalysts, and the presence of metal ions, as well as the factors of time, pH and initial DBP concentration. Given that it did not exceed 31%, the degradation of DBP we achieved using H〈sub〉2〈/sub〉O〈sub〉2〈/sub〉 could not be regarded as satisfactory. In contrast, the addition of 2.5 mM L〈sup〉−1〈/sup〉 of Fe〈sup〉2+〈/sup〉 was found to mediate almost complete elimination of the phthalate from the model solution. Also confirmed by experimentation were the benefits of using homogeneous catalysts (compounds of copper(II) and manganese(II)) as alternatives to Fe〈sup〉2+〈/sup〉 in the Fenton reagent. A key experimental achievement was to confirm the applicability of a catalyst formed from a mixture of 2 or 3 types of transition metal ion. A Fenton reaction extended to ions like Mn〈sup〉2+〈/sup〉 and Cu〈sup〉2+〈/sup〉 in particular is seen to eliminate factors/parameters discouraging practical industrial use of the classic Fenton process.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519316741-egi10GVRZX8LGR.jpg" width="354" alt="Image 108" title="Image 108"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Yuandong Wu, Yanlong Sun, Chengzhi Zhou, Junfeng Niu〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract:〈/h5〉 〈div〉〈p〉A regeneration method for porous electrospun membranes embedding alumina nanoparticles saturated with minocycline was investigated by UV-LED system. The percentage of adsorption capacities before and after regeneration were used to evaluate regeneration efficiency. The PVDF and PVDF-Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 fiber mats were prepared by electrospinning technique. Scanning electron microscope (SEM), transmission electron microscope (TEM), energy-dispersive X-ray spectroscopy (EDS) analyses directly confirmed that Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 nanoparticles were generally exposed to the surface of PVDF-Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 fiber mats. Among them, PVDF-Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 10% fiber mats can effectively adsorb minocycline (remove efficiency 〉97% in 18 h) with first-order rate constant 〈em〉k〈/em〉 = 2.253 ± 0.331 h〈sup〉−1〈/sup〉. The sorption capacity can still keep 81% after five sorption/UV-regeneration circulations. Two successional stages may exist during regeneration: (i) transfer of minocycline from the surface of PVDF-Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 fibers to the DI water, followed by the (ii) decomposition of this compound in aqueous solution by direct and indirect photolysis to yield the intermediate species. The desorption capacity and desorption percentage were 4.39 mg g〈sup〉−1〈/sup〉 and 23.30% respectively. The regeneration yields were further enhanced to 94.20% by UV radiation. Minocycline was effectively degraded to intermediate products by direct and indirect photolysis, further degraded into CO〈sub〉2〈/sub〉, H〈sub〉2〈/sub〉O, and NO〈sub〉x〈/sub〉 by UV-generated ozone during regeneration. The results indicated that UV radiation was an effective method of regenerating PVDF-Al〈sub〉2〈/sub〉O〈sub〉3〈/sub〉 fiber mats with low energy requirements. The photochemical byproducts and the reaction sites during regeneration were also determined and recognized.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519317199-fx1.jpg" width="283" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Manish Kumar, Ritusmita Goswami, Neeraj Awasthi, Reshmi Das〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉In this work we present a completely new dataset of Rare Earth Element (REE) distribution and fractionation in the groundwater and sediments of the world's largest populated river island-Majuli, located in the Brahmaputra River, India. Groundwater (n = 9) and borehole sediments (n = 23) of different depths were collected randomly and analyzed for REEs using inductively coupled plasma mass spectrometry (ICP-MS). Multivariate statistical techniques were applied to determine interrelationships among different REEs. Both water and sediments exhibit a higher content of light rare earth elements (LREEs) than heavy rare earth elements (HREEs), implying that source rock composition primarily controls the REE signatures of these river sediments, largely owing to variations in levels of chlorite and monazite, which are more abundant in bottom river sediments of the Brahmaputra. However, lower LREE/HREE ratios in groundwater samples (8.42–14.48) compared to sediments (8.9–52.6) suggest less dissolved phase mobilization of LREE during weathering and transport. Hierarchical cluster analysis showed more consistent clustering in sediment compared to water and clear demarcations of MREE, HREE and LREE were observed in the sediments. The primitive mantle-normalized REE patterns of borehole sediments were similar to the upper continental crust (UCC) and the compositions of average Himalayan rocks. LREE enrichment compared to HREE suggest dominance of a felsic source. However, a La/V versus Th/Yb plot suggests a small contribution from the mafic source component. The sediments show high Th/Sc (〉1 of UCC) and high Zr/Sc. A Eu/Eu* verses Gd〈sub〉N〈/sub〉/Yb〈sub〉N〈/sub〉 plot suggests that the dominant source with Upper crustal composition has undergone multiple recycling.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519317011-fx1.jpg" width="336" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Lihai Hu, Diego P. Fernandez, Thure E. Cerling〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉As a recorder containing both physiological and environmental information, keratinized tissues, such as hair and feather, can be used to reveal geographical information, to monitor the exposure to pollutants, and to reconstruct dietary history. However, trace element analysis of keratinized tissues is complicated by the lack of reference endogenous ranges of trace element and the lack of understanding of the susceptibility of each element to exogenous contamination. The interior of animal horn is the cleanest of all keratinized tissues with minimum exogenous contamination because of its large size. Thus, the trace element concentrations in horn interior samples can provide reliable endogenous concentration ranges. Here we measured the concentrations of trace elements in horn interior samples of cattle and wild animals, which we propose to be used as the reference ranges for endogenous levels of trace elements in keratin. We calculated the enrichment factors of 30 trace elements in horn interior samples relative to the continental crust, which we considered the average exogenous contamination. We compared the ranges of elemental concentrations measured in horn interior samples, in the order of decreasing enrichment factor, to their reference ranges in hair, fingernails, and toenails, as well as their concentrations in caprine horns. Such comparison validates the use of the enrichment factor as an indicator of the susceptibility of an element to contamination: an element with a high enrichment factor is generally less likely to be affected by contamination and vice versa.〈/p〉〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Shaogang Chu, Robert J. Letcher〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The present study investigated the metabolism of the flame retardant and plasticizer chemical, triphenyl phosphate (TPHP), in a rat liver microsome-based 〈em〉in vitro〈/em〉 assay with glutathione (GSH) in order to elucidate metabolic pathways leading to formation of conjugates. A highly sensitive and efficient method was developed for the detection and characterization of GSH reactive metabolites using LC-Q-TOF-MS/MS both in the negative and positive electrospray ionization modes. Seven GSH conjugates formed as a result of microsomal incubation, which were identified as S-conjugates based on MS/MS spectra, and confirmed by subsequent time-dependent incubation assays. With the exception of hydrolysis reactions leading to formation of a diester metabolite, diphenyl phosphate (DPHP), the results demonstrated that Phase I epoxidation on phenyl ring of TPHP leading to mono- and di-hydroxylated TPHP metabolites, which can further conjugate with GSH. Depending on hydroxylated TPHP formation, an 〈em〉o〈/em〉-hydroquinone intermediate formed 〈em〉in vitro〈/em〉 via Phase I metabolism, and the 〈em〉o〈/em〉-benzoquinone form reacted with GSH and also formed GSH conjugates. The present study showed that via hydroxylated TPHP Phase I formation that GSH conjugates are important Phase II metabolites for TPHP metabolism 〈em〉in vitro〈/em〉. Some GSH conjugates may be valuable candidate biomarkers for monitoring TPHP exposure in biota.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519316984-fx1.jpg" width="318" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Juan Carlos Fernández-Caliani, María Inmaculada Giráldez, Cinta Barba-Brioso〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉 〈p〉Cultivated soils around the historic mine site of Tharsis (Spain) contain elevated concentrations of As (up to 621 mg kg〈sup〉−1〈/sup〉), Cu (752 mg kg〈sup〉−1〈/sup〉) and Pb (2395 mg kg〈sup〉−1〈/sup〉), exceeding the regional background levels and the statutory limits set for agricultural use. A site-specific health risk assessment of occupational and environmental exposures was conducted using an approach based on guidelines from regulatory agencies, refined by combining bioaccessibility and bioavailability data.〈/p〉 〈p〉Oral bioaccessibility, as determined by simulating the human digestion process 〈em〉in vitro〈/em〉 (Unified BARGE Method), was largely related to total trace element concentrations in soil. Arsenic seemed to be evenly distributed among the gastric and gastro-intestinal phases (about 31%), whereas the bioaccessible fraction of pH-dependent metal cations, like Pb and Zn, was noticeably higher in the stomach (nearly 50%) than in the gastro-intestinal tract (less than 10%). Bioaccessibility assessed by single extraction with 0.43 M HNO3 was overestimated by a factor of 1.2–1.4 relative to that obtained from the BARGE method.〈/p〉 〈p〉Site-specific relative bioavailability (RBA) values of As (27.7%) and Pb (42.6%), predicted from bioaccessibility measurements through linear regression models, had little effect on the overall risk estimates. For the ingestion pathway, the RBA-adjusted cancer risk values (9.7E-05 to 2.0E-04) exceeded the regulatory threshold in all plots, and the hazard index re-calculated after adjustment of oral dose was also above the allowable limit, with values ranging from 2.5 to 4.8. However, no detrimental health effects are expected to occur through inhalation of soil particles in nearby residents.〈/p〉 〈/div〉 〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): Imtiaz Afzal Khan, Yong-Soo Lee, Jong-Oh Kim〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The goal of this study was to identify the scaling from the chemical cleaning of a polyvinylidene fluoride (PVDF) membrane, fouled by treating a solution containing inorganic foulants (Al, Fe, and Mn) in the presence of kaolin and humic acid as a natural organic matter at Ca〈sup〉+2〈/sup〉 strength of 0.5 mMole. Chemical cleaning of the membrane was conducted using solutions prepared in deionized water and permeate water (PW), and the accumulation of insoluble salts on the membrane during cleaning were evaluated. Energy dispersive spectroscopy analysis was used to verify the presence inorganic foulants, and field emission scanning electron microscopy confirmed the changes in membrane symmetry from the accumulation of the foulants. A Fourier-transformed infrared spectroscopy analysis indicated the presence of new functional groups, i.e., C˗Cl and C˗O with bond vibrations at 542 cm 〈sup〉−1〈/sup〉 and 1,026 cm〈sup〉−1〈/sup〉, respectively, on the membrane surface. The adsorbed mass of HA in the presence of inorganic foulants decreased from 3.54 ± 0.045 mg to 2.24 ± 0.095 mg and 1.71 ± 0.075 mg, and the flux recoveries decreased from 93.2% to 85.69% and 81.92%, for the pristine to chemically DI and PW cleaned membrane, respectively. However, the membrane characterization results confirmed that Al was the major contributor to the accumulation of inorganic salts on the membrane during chemical cleaning and its role was more severe in the presence of Mn. The fitting results of Hermia's fouling models and a specific fouling analysis confirmed the contribution of complete blocking model with increase in irreversible fouling was observed after chemical cleaning.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S0045653519316194-fx1.jpg" width="402" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉

Description: 〈p〉Publication date: December 2019〈/p〉 〈p〉〈b〉Source:〈/b〉 Chemosphere, Volume 237〈/p〉 〈p〉Author(s): S.G. Luo, S.C. Chen, W.Z. Cao, W.H. Lin, Y.T. Sheu, C.M. Kao〈/p〉 〈div xml:lang="en"〉 〈h5〉Abstract〈/h5〉 〈div〉〈p〉The effectiveness of using gamma poly-glutamic acid (γ-PGA) as the primary carbon and nitrogen sources to bioremediate trichloroethene (TCE)-contaminated groundwater was studied in this pilot-scale study. γ-PGA (40 L) solution was injected into the aquifer via the injection well (IW) for substrate supplement. Groundwater samples were collected from monitor wells and IW and analyzed for TCE and its byproducts, geochemical indicators, dechlorinating bacteria, and microbial diversity periodically. Injected γ-PGA resulted in an increase in total organic carbon (TOC) (up to 9820 mg/L in IW), and the TOC biodegradation caused the formation of anaerobic conditions. Increased ammonia concentration (because of amine release from γ-PGA) resulted in the neutral condition in groundwater, which benefited the growth of 〈em〉Dehalococcoides〈/em〉. The negative zeta potential and micro-scale diameter of γ-PGA allowed its globule to distribute evenly within soil pores. Up to 93% of TCE removal was observed (TCE dropped from 0.14 to 0.01 mg/L) after 59 days of γ-PGA injection, and TCE dechlorination byproducts were also biodegraded subsequently. Next generation sequence (NGS) analyses were applied to determine the dominant bacterial communities. γ-PGA supplement developed reductive dechlorinating conditions and caused variations in microbial diversity and dominant bacterial species. The dominant four groups of bacterial communities including dechlorinating bacteria, vinyl chloride degrading bacteria, hydrogen producing bacteria, and carbon biodegrading bacteria.〈/p〉〈/div〉 〈/div〉 〈h5〉Graphical abstract〈/h5〉 〈div〉〈p〉〈figure〉〈img src="https://ars.els-cdn.com/content/image/1-s2.0-S004565351931673X-fx1.jpg" width="415" alt="Image 1" title="Image 1"〉〈/figure〉〈/p〉〈/div〉