ALBERT

Notizen: Abstract. Human plasma samples from 50 wives of fishermen have been analyzed with respect to PCBs. The non-ortho-substituted PCB congeners CB-126 and CB-169 were determined by mass spectrometry in negative ion chemical ionization mode, which demonstrated a limit of detection of 30 fg. The recoveries of the internal standards used for determination of ortho-substituted CBs were approximately 95%. Two methods, one gravimetric and the other based on enzymatic determinations of triglycerides, cholesterol and phospholipids, were compared for the determination of total amount of lipids in the plasma samples; the correlation coefficient was 0.82 and the slope 0.98. For practical reasons, enzymatic determinations are recommended for further use. The total, lipid-adjusted concentrations of PCBs in plasma were influenced by age, total lactation time and consumption of fatty fish from the Baltic Sea.

Notizen: Abstract The effects of the herbicide 4(2,4-dichlorophenoxy)butyric acid (2,4-DB) and fungicideN-(trichloromethyltio)-4-cyclohexene-1,2-dicarboximide (captan) on electron transport processes of mitochondria and chloroplasts have been investigated. Chloroplasts, isolated from spinach leaves (Spinacia oleracea L.), were treated with pesticide prior to the addition of electron acceptor and ADP. White potato (Solanum tuberosum L.) mitochondria were either incubated with pesticide before the addition of substrate, or they were treated with pesticide after the addition of substrate and ADP. Captan inhibited oxidation of malate by mitochondria and acted as an uncoupler. With succinate as sunstrate captan was found to stimulate state 4 respiration, as substrate captan was found to stimulate state 4 respiration, with the loss of coupled phosphorylation only at higher concentrations of fungicide. The herbicide 2,4-DB appeared to be 5 to 10 times less effective than captain. Both compounds inhibited phosphorylationcoupled succinate oxidation at higher concentrations and malate-coupled phosphorylation at lower concentrations. They acted as inhibitors of NADH-cytochrome c reductase. Both pesticides inhibited noncyclic electron transport in chloroplasts. The rate of ferricyanide reduction in the presence and absence of phosphorylating agents was reduced, and although the rate of ATP generation was reduced also, the P/2e ratio was not changed much under the influence of pesticides.

Notizen: Abstract Young growing lambs and pigs were fed a ration containing 200 ppm of Aroclor 1254 for 35 days and then switched to “clean” feed. Blood and fat samples were collected periodically throughout the experiment and analyzed for components of Aroclor 1254 and total PCB. Several components are apparently accumulated and eliminated at different rates within each species, as seen by comparing gas chromatograph tracings, accumulation ratios and apparent rate constants of elimination. Differences in accumulation and elimination of Aroclor components, some of which were apparently caused by differences in growth rates, were also seen between pigs and lambs. Variable growth rates of different species of food producing animals are an important factor to consider when dealing with tissue distribution and residues of polychlorinated biphenyls for determination of carcass disposition, as well as accumulation of toxic concentrations in the animal body.

Notizen: Abstract Groups of 30Xenopus laevis embryos, at “tail-bud” stage (Nieukoop-Faber stages 22–24) were exposed to 0.1–2 ppm concentrations of various pesticides for 1 to 10 days. The pesticides used were chloranil and dichlone (both are fungicidal and herbicidal); diquat (herbicide); and nabam (fungicide). The parameters examined were mortality, gross morphology, histology, and behavior. Chloranil (1.25 to 1.75 ppm) treated embryos showed abnormalities of the otolith, optic cup, and general pigmentation. Their movement was sporadically convulsive and they were unable to maintain proper balance. Dichlone (0.1 to 0.15 ppm) disrupted the development of the cephalic end of the embryo. Many of these embryos developed a slightly retarded trunk and tail only. These headless embryos lived for a time and were relatively lethargic. Diquat (0.75 to 2.0 ppm) administration reduced body size and pigmentation, and altered body shape. When embryos were treated with both 1.0 ppm of diquat and 2.0 ppm of nabam the integrity of myomeres and myocommata of the musculature was disrupted. The histological bases of these morphological and behavioral changes are discussed.

Notizen: Abstract Eastern oysters (Crassostrea virginica) were found to accumulate significant levels of mercury on exposure to relatively low concentrations of mercuric chloride. Accumulation occurred in two distinct phases which may be described as a two compartment system in which accumulation is logarithmic in the first phase and linear in the second. Mercury, during the initial phase, showed a minimum outward concentration flux of 0.025 hr−1 indicating reversibility of accumulation prior to the change in phase. However, mercury was not excreted at the end of the second phase following exposure to 10, 40, 80, and 100Μg/1 for 256 hr.

Notizen: Abstract Disappearance of monocrotophos from flue-cured tobacco was studied at three locations (Kinston, Clayton, and Reidsville, North Carolina) in 1973. Average residues on green tobacco leaves collected immediately after application were 41 and 84 ppm, respectively, for applicaton rates of 0.56 and 1.12 kg/ha. Levels declined to about 18 and 40 ppm for the two rates three days after application, to about 9 and 23 ppm at five days, and to about three and eight ppm at nine days. Conventional curing reduced residues on flue-cured tobacco by at least 99%.

Notizen: Abstract Experimental communities of various estuarine animals in outdoor tanks were exposed to a continuous flow of water containing mirex for 10 weeks. The mirex was leached from fire ant bait (0.3% active ingredient) by fresh water which was then mixed with salt water to yield exposure concentrations averaging 0.038Μg/L. The experiment simulated runoff from treated land into estuarine areas. Mortality of grass shrimp (Palaemonetes vulgaris), pink shrimp (Penaeus duorarum), common mud crabs (Panopeus herbstii), and striped hermit crabs (Clibanarius vittatus) was significantly higher in tanks containing the toxicant. Mortality of ribbed mussels (Modiolus demissus) and American oysters (Crassostrea virginica) was significantly lower in treated tanks, probably because numbers of both species of crabs, which ate the bivalves, were reduced. Sheepshead minnows (Cyprinodon variegatus) were least affected by mirex. Almost all deaths occurred after 10 or more days of exposure. All exposed animals accumulated mirex, with maximum concentrations ranging from 5,500X (pink shrimp) to 73,700X (soft tissues of oysters) above the concentration in the water. Sand substratum contained mirex up to 1,500X that in the water. The study demonstrated that mirex can be leached from bait by fresh water and concentrated by and affect survival of members in an experimental estuarine community.

Notizen: Abstract 2,4-D in plants very rapidly undergoes various transformations and its predominant metabolic pathways and rates vary with different plant species. In bean and soybean plants major 2,4-D metabolites are 4-O-Β-D-glucosides of 4-hydroxy-2,5-dichloro- and 4-hydroxy-2,3-dichloro-phenoxy-acetic acids; in addition, considerable amounts ofN-(2,4-dichlorophenoxyacetyl)-L-aspartic andN-(2,4-dichlorophenoxyacetyl)-L-glutamic acids are accumulating in them. Among 2,4-D metabolites in cereals there prevailed 1-O-(2,4-dichlorophenoxyacetyl)-Β-D-glucose while the glycoside of 2,4-dichlorophenol prevailed in strawberry plants.

Notizen: Abstract The herbicides 2,4-D and 2,4,5-T and many of the esters of these compounds produced cleft palates in CD-1 mice. Silvex and Agent Orange also produced cleft palates. Depending on the dose and means of administration variable responses relating to the production of cleft palates, effect on fetal weight, and effect on fetal mortality were obtained. In order to view these data comprehensibly, the Prenatal Development Index was determined. This index was computed from the incidence of malformed fetuses, fetal mortality and fetal body weight. This made it possible to evaluate data from some experiments with feto-toxic doses of compounds in which the high incidence of fetal mortality and consequently low incidence of viable fetuses obscured the response.

Notizen: Abstract Gas chromatographic (GLC) detection of arylN-methylcarbamates as theN-acetyI-Clx orN-nitroso derivatives of the intact molecule was explored using carbaryl as the model compound. These derivatives were designed for use with the microcoulometric detector for chlorine and the solution conductivity detector for nitrogen but response to the electron capture detector was also studied. GLC characteristics of the derivatives were evaluated in terms of thermal stability and detector response. N-Trichloracetyl andN-nitroso carbaryl underwent extensive decomposition in the GLC system. Although theN-monochloroacetyl derivatives were also subject to thermal decomposition, they gave sufficient linearity and sensitivity with the microcoulometric detector for analysis at the residue level.N-Acetyl carbaryl was thermally stable and the response of electrolytic conductivity and the electron capture detectors were adequate for residue analysis.

Notizen: Abstract The continuous feeding of the polychlorinated biphenyl mixture Aroclor 1254 to rats produced varying degrees of dermatitis, first on the ears and later on the nose, tail and feet. The lesions were first observed 10 weeks after the rats began eating chow in which the PCB was present. The lesion consisted of alopecia, and the skin was rough, reddened and thickened. Microscopically, there was hyperkeratosis and parakeratosis, and the subcutaneous tissue was edematous, and sometimes infiltrated with inflammatory cells. The lesions were encrusted by desiccated serum which had escaped through small fissures in the epithelium. This lesion was found in 15 of 60 animals fed the PCB at 100 ppm, 4 of 60 at 30 ppm and 1 of 60 at 10 ppm for 10 to 20 weeks. The livers of the PCB-treated rats were enlarged and fluoresced under ultraviolet light. Microscopically, the central lobular hepatocytes were enlarged, there was an accumulation of an iron positive brown pigment in Kupffer cells, and there were central and midzonal foci of necrosis accompanied by inflammation.

Notizen: Abstract The behavioral reactions of a range of stream macroinvertebrates to short exposures to the organophosphorus insecticides temephos and chlorpyrifos methyl in running water have been studied in a laboratory experimental channel or simulated stream. The tests showed widely different types of response not only in accordance with susceptibility levels previously established, but also with regard to activation responses leading to detachment and downstream drift. The amphipodGammarus pulex was the most readily activated by both insecticides, even at sub-lethal levels. Nymphs of the mayflyBaetis rhodani were also readily activated, but to a less extent than would be expected in view of their established high susceptibility to both compounds. In the case ofSimulium larvae, detachment leading to drift during the 30-min exposure period was negligible with late instars exposed to each of the two insecticides, even at lethal levels. Both types of caddis larvae tested, the web-spinningHydropsyche pellucidula and the mobile case-bearingBrachycentrus subnubilis, showed little sign of activation to either insecticide, even at concentrations which subsequently produced high mortalities. Observations extended for up to 24 hr after the initial 30-min exposure, showed continued complete absence of activation and detachment, the majority of exposed larvae dyingin situ. These differences in reaction are discussed in relation to the interpretation of downstream drift following field application of these chemicals in practical and experimentalSimulium control.

Notizen: Abstract Warm-(17°C) and cold-acclimated (8°C) young-of-the-year, 1-year-old, and 2-year-old common shiners,Notropis cornutus (Mitchill) were exposed for 24 hr to sublethal doses (1.0, 0.25, and 0.05μg/L) of malathion to determine the effect of environmental concentrations of this compound on temperature selection. All three factors studied (acclimation temperature, age, and concentration) were found to affect the temperature selection response of malathion-treated fish. Malathion produced dose-dependent decreases in selected temperature (1.9° to 4.3°C below controls) in 17°C-acclimated fish but not in 8°C-acclimated fish. Two-year-olds treated with 1.0μg/L displayed the greatest lowering of selected temperature, followed by two-year-olds treated with 0.25μg/L. One-year-olds treated with 1.0μg/L showed a slight lowering, while no downward shifts in selected temperature were found for young-of-the-year. Exposure to 0.05μg/L had no effect on any age group. Two-year-olds acclimated to 17°C and exposed to 1.0μg/L malathion for 24 hr were placed in clean water and allowed to recover from the pesticide. It was found that the lowered selected temperature induced by malathion returned to that of the controls in 24 hr.

Notizen: Abstract The exposure of blue gouramis to 9 ppb of methylmercury, copper, or methylmercury + copper resulted in an apparent decrease in the immune response of these fish to both infectious pancreatic necrosis (IPN) virus andProteus vulgaris. The two toxicants jointly, however, produced no greater or lesser effect than when each compound was applied singly. In recent years much work has been concerned with the determination of various contaminants in the environment and in the establishment of the tolerance limits for these compounds. The heavy metals are some of the most toxic compounds to aquatic organisms, and of these, mercury and copper are among the most toxic. Recent studies (Roales and Perlmutter 1974) have established the median tolerance limit (Tlm) for methylmercury and copper to the blue gourami (Trichogaster trichopterus), and indicate that the two toxicants might interact antagonistically. The immune response of fishes has been the subject of much study (Smithet al. 1966, Snieszko 1970). Recently, the immune response of the blue gourami to viral (Yuet al. 1969 and 1970, Perlmutteret al. 1973) and bacterial (Roales and Perlmutter 1975) antigens has been studied. Mount (1968) determined that 3 to 7% of the 96-hr Tlm was the safe limit for fathead minnows exposed to copper. Rachlin and Perlmutter (1968) demonstrated that 10% of the 96-hr Tlm was the safest concentration for fathead minnows exposed to zinc. Although these levels are considered to be safe, it is possible that they are safe only so far as their toxicity or their effects on growth and reproduction are concerned. Quite possibly, safe doses of toxicants may affect fishes in less obvious manners. Lead (Hemphillet al. 1971), cadmimum (Joneset al. 1971) and DDT (Wassermannet al. 1971) have been shown to reduce the immune response of mammals. Recent work (Sarot 1973) has shown that zinc decreases antibody production in the zebrafish.

Notizen: Abstract Acute toxicity of hydrogen cyanide was determined at various temperatures from 4° to 30°C and oxygen concentrations of 3.36 to 9.26 mg/L on different life history stages of five species of fish: fathead minnow,Pimephales promelas Refinesque; bluegill,Lepomis macrochirus Rafinesque yellow perch,Perca flavescens (Mitchill); brook trout,Salvelinus fontinalis (Mitchill); and rainbow trout,Salmo gairdneri Richardson. Median lethal threshold concentrations and 96-hr LC50's were established by flow-through type bioassays. Acute toxicity varied from 57μg/L for juvenile rainbow trout to 191μg/L for field stocks of juvenile fathead minnows. Juvenile fish were more sensitive at lower temperatures and at oxygen levels below 5 mg/L. For most species juveniles were most sensitive and eggs more resistant.

Notizen: Abstract The fate of TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin) was studied by using aquatic sediment and lake water under laboratory conditions. Most of the TCDD was found in the sediment from which it slowly disappeared. Evaporation may be a major mode of disappearance of TCDD in samples incubated 39 days or more, with metabolism playing only a minor role. Under the experimental conditions the half-life of TCDD was in the order of 600 days. The metabolic activities were enhanced under conditions which stimulated microbial growth in the presence of sediment, and the metabolites were found to be released from the sediment to the ambient water.

Notizen: Abstract Acclimation temperature influenced the acute preferred temperature of the crayfishOrconectes obscurus. This species preferred a higher temperature than its acclimation temperature for those acclimation temperatures ranging from 6° to 26°C. When acclimated to 30° and 33°C, the crayfish preferred a lower temperature than its acclimation temperature. The final temperature preferendum is estimated to be approximately 30°C.

Notizen: Abstract Organochlorine pesticide concentrations in blood and various clinical test variables were measured in 2,620 pesticide-exposed subjects and in 1,049 persons not occupationally exposed to pesticides. Differences in the pesticide contents of blood were identified in relation to geography, age, and occupational exposure. Analysis of hematologic and biochemical variables in terms of broad occupational categories revealed only very limited differences, but relationships of certain biochemical tests to serum organochlorine pesticide contents suggested subtle effects of these pesticides on liver function.

Notizen: Abstract Five series of organic contaminants associated with aqueous coalconversion effluents were studied to determine the correlation between their known partition coefficients in the octanol-water system and their toxicity to the ciliateTetrahymena pyriformis. In all five series, toxicity increased and solubility decreased with increased alkyl substitution. Compounds containing the equivalent of two or more methyl groups are more toxic than those with one or no alkyl substitutions.

Notizen: Abstract The effects of the insect growth regulator (IGR) diflubenzuron [1-(4-chlorophenyl)-3(2,6-difluorobenzoyl)-urea] on planktonic, nektonic, and benthic invertebrates in a residential-recreational lake were studied during the period of April to October 1977. A 25% WP formulation of the IGR was applied at 156 g AI/ha (0.012 ppm) to the entire lake surface, once on April 26, and again on August 24. The April treatment severely affected populations of the cladoceransDaphnia laevis Birge,Ceriodaphnia sp.,Bosmina longirostris (O. F. Muller), and the copepodsCyclops spp. andDiaptomus sp., completely eliminating them within one week posttreatment.Daphnia andCeriodaphnia did not recover even after 6 months of treatment butB. longirostris reappeared 11 weeks posttreatment.Diaptomus was depleted for four months, whileCyclops recovered within six to seven weeks after treatment. The amphipodHyalella azteca (Saussure) was completely eliminated within four weeks remaining absent for more than six months after the treatment. The prolonged absence of these nontarget organisms following treatment is probably due to the seasonal cycle of the species involved and the inability of some of the taxa to rapidly recolonize the treated habitat. Nymphs of the mayfly,Caenis sp., were reduced 99%, recovering in six weeks posttreatment. The IGR had no adverse effects on oligochaetes (Naididae and Tubificidae), Hydrachnellid mites, the gastropodPhysa sp., and the ostracodCypridopsis sp. The second application in August caused complete elimination ofCyclops andB. longirostris within one to two weeks, the former recovering in four weeks and the latter in eight to nine weeks after the treatment.Caenis, also was adversely affected, recoveringin four to five weeks posttreatment. No significant reduction in Cypridopsid, Hydrachnellid, Physid, or oligochaete populations was noted.

Notizen: Abstract Duplicate static bioassays were conducted using a simulated refinery effluent on the grass shrimp (Palaemonetes pugio, Hippolyte sp.) with the LC-50 values recorded at 4-, 8-, 24-, 48-, and 96-hr intervals. The simulated refinery effluent contained phenol (0.10 mg/L), sulfide (0.17 mg/L), chromium (0.25 mg/L), ammonia (10 mg/L), No. 2 fuel oil (10 mg/L), and kaolinite (20 mg/L). This arbitrary reference mixture (ARM) contains approximately the concentration of compounds recommended by EPA for 1977. Of the six ARM components, No. 2 fuel oil was the most toxic followed in decreasing order by sulfide, ammonia, phenol, chromium, and kaolinite. Temperature was the most important environmental variable affecting short term toxicity of the ARM to the grass shrimp. Light intensity, photo-period, and salinity had no significant effect. There was no difference in sensitivity of grass shrimp collected from five locations along the gulf and eastern coasts of the United States. Similarly, there was no difference in the response of two grass shrimp genera,Palaemonetes andHippolyte to the ARM and there were no differences among the three species ofPalaemonetes tested. In comparing the sensitivities of the two genera of grass shrimp and the pinfish (Lagodon rhombroides) to the ARM, the grass shrimp were more sensitive.

Notizen: Abstract When the rate of movement and the persistence of aldicarb in 4 types of soils were investigated in laboratory and field studies some leaching was detected in coarse sand; however, leaching was quite limited in clay loam and muck soils. These data indicated that aldicarb degraded quite rapidly in the selected soils and most of the applied radioactivity volatilized from these soil columns as14CO2. The evolution of14CO2 from the treated soil suggested severe degradation of the aldicarb molecule and consequently provided indirect evidence against the accumulation of significant quantities of toxic metabolites in the soil types evaluated. Under field conditions this toxicant appeared to have a half-life of about 7 days in loam soil.

Notizen: Abstract Acetyl-Clx (x=0,1,2 or 3) and nitroso derivatives of carbaryl, 1-naphthol, 5-hydroxycarbaryl, and 1,5-naphthalenediol were synthesized. Compounds were characterized by infrared, mass, and nuclear magnetic resonance spectroscopy. N-chloroacetylation (Cl=0,1,2, or 3) of carbaryl was readily accomplished through the pyridine-catalyzed reaction of carbaryl with the appropriate acid chlorides. Trichloroacetylation was also possible through the pyridine-catalyzed reaction with the anhydride.N-nitrosation could also be done readily.N-nitroso- andN-trichloroacetyl carbaryl underwent decomposition to carbaryl on exposure to atmospheric moisture and could be maintained in the pure state only with difficulty. The other derivatives were stable under normal storage conditions.

Notizen: Abstract A replicated field experiment was conducted at two locations to determine the disappearance of methomyl from flue-cured tobacco. Immediately after application, methomyl residues were 88 and 113 ppm at Clayton and 44 and 105 ppm at Reidsville, respectively, for 0.56 and 1.12 kg/ha application rates. After 5 days these levels dropped to 0.7 and 2.8 ppm at Clayton and 1.4 and 4.1 ppm at Reidsville. At 9 days after application, 99% of the methomyl had disappeared at both locations. Losses of methomyl during flue-curing averaged 96% over locations, rates of application, and times of harvest, compared to an average loss of 98% due to weathering in the field for 5 days. The disappearance of methomyl during the curing process was approximately the same for both locations.

Notizen: Abstract Growing swine and sheep were fed three dietary variations containing 20 ppm of Aroclors 1242 or 1254 for 13 to 15 weeks. Generally, Aroclor 1254 residues were higher; higher 1242 residues in swine blood, spleen, and ovary are attributed to persistent major components of this Aroclor. Some minor differences in total PCB were observed with varying diets, but peak composition did not vary. Some lower chlorinated components maintained higher levels in the blood relative to other components; other components were selectively accumulated in tissues such as fat and muscle. Blood and fat residues in sheep declined during the last weeks of feeding. Microsomal oxidase levels were elevated in response to PCB and diet in both species, but the response was greater in sheep. Sheep liver microsomes were capable of metabolizing pure analogs and components of Aroclor 1242. Major differences in Aroclor profiles can be demonstrated between swine and sheep residues and total residues can be estimated by measuring selected peaks in blood and backfat. The peaks which provide the most reliable estimate of total PCB residue vary with species and Aroclor.

Notizen: Abstract The toxicity of tetramethyl lead (Me4Pb) towards freshwater algae was studied by bubbling biologically generated Me4Pb from one flask containing 5 mg of Pb l−1 as Me3PbOAc into the culture medium in another flask where a test algaScenedesmus quadricauda was grown. As Me4Pb is not soluble in water and is volatile, the exposure of an alga to this lead compound was only momentary. It was estimated that less than 0.5 mg of Pb (Me4Pb) had passed through the culture medium. The primary productivity and cell growth (determined by dry weight), however, decreased by 85% and 32% respectively, as compared with the controls without exposure to Me4Pb. Furthermore, cells exposed to Me4Pb tended to clump together and striking alterations in cell fine-structure were observed. An electron microscopic analysis by an energy dispersive spectrometer revealed that Pb ions had penetrated the cell and were deposited within concretion bodies. Similar results were obtained with the green algaeAnkistrodesmus falcatus andChlorella pyrenoidosa.

Notizen: Abstract PCB translocation from soil into a plant through its roots was investigated by a method of culture of soybean sprouts on sand contaminated with Aroclor 1242 or 1254. A preliminary culture was carried out on clean sand in a cage with small holes in the bottom and then followed by a main culture on contaminated sand after the preliminary culture cage was placed upon a box filled with the contaminated sand. Consequently roots of soybean sprouts were allowed to penetrate through the holes at the bottom of the upper cage into the contaminated sand. Rates of transference of PCBs were found to be different among chlorobiphenyl isomers; low chlorobiphenyls were much more preferentially absorbed by sprouts than were the high chlorobiphenyls. This seemed to depend mostly on different water solubilities of the isomers and probably not on selective absorption of the isomers by sprouts. The usefulness of the method employed of the two-steps sprout culture on doubly layered soil, in investigations of translocation mechanisms of toxic chemicals in a soil-plant ecosystem, is also discussed.

Notizen: Abstract Morestan (6-methyl-2,3-quinoxalinedithiol cyclic-S,S carbonate) and two of its metabolites: methyl-2,3-quinoxalinedithiol and 6-methyl-2,3-quinoxalinedihydroxy were administered to male and female rats by intraperitoneal route for 4 consecutive days (50 mg/ kg/daily). Morestan was also administered by esophageal intubation for 4 days at the dose of 75 mg/kg/daily. After evaluating the pentobarbital sleeping time in the animals on the 5th day, aminopyrineN-demethylase,p-nitroanisoleO-demethylase and aromatic aniline hydroxylase activities and levels of cytochrome P450, proteins and RNA were measured in the microsomal hepatic fraction. Protein and nucleic acid levels were also measured in whole liver. The 3 substances studied caused considerable decreases in activity of certain microsomal enzymes: morestan inhibits some hepatic mixed-function oxidase systems; in females it is more active by peroral administration, and in males by intraperitoneal route. However, 6-methyl-2,3-quinoxalinedithiol is an even more powerful inhibitor of monooxygenase activities both in males and females. 6-methyl-2,3-quinoxalinedihydroxy also decreases activity by microsomal enzymes, but its action is inferior to that of the other two products investigated.

Notizen: Abstract A general colorimetric method has been developed to analyze either anionic or cationic surfactants in fresh water. An appropriate dye will react with ionic surfactant to form a chloroform-soluble, colored complex in the presence of chloroform. The color intensity of the vigorously rocked and subsequently settled chloroform layer is proportional to the concentration of the “dye-ionic surfactant complex”, and can then be measured by making spectrophotometric readings of the chloroform solution at the optimum wavelength of the instrument used. When cationic surfactants are to be analyzed, methyl orange shall be used as a dye; when anionic surfactants are to be analyzed, azure A or methylene blue shall be used as a dye. Other chemical reagents, apparatus and spectrophotometers, however, can be nearly identical for either cationic surfactant or anionic surfactant measurement. This new analytical method is stoichiometric, and can be easily performed by a laboratory technician within a very short period of time.

Notizen: Abstract Toxicity, residue dynamics, and biological effects of polychlorinated biphenyls (Aroclor® series) were investigated in several freshwater invertebrates and fishes. Acute static toxicities (LC50) of PCB's ranged from 3.2 to 2,400Μg/L for invertebrates and from 1.2 to 61 mg/L for fish. The LC50's for invertebrates exposed in flow-through diluter systems for 5 to 10 days were 0.6 to 80Μg/L and those for fish exposed for 30 days were 3.0 to 433Μg/L. Invertebrates accumulated Aroclor 1254 residues up to 6,300 times greater than those to which they were exposed. Biological accumulation of Aroclors 1248 and 1254 by channel catfish (Ictalurus punctatus) was 56,370 to 61,190 times the levels in water after 77 days. Dietary exposures of coho salmon (Oncorhynchus kisutch) to Aroclor 1254 at rates of 1.45 to 14,500Μg/kg body weight per day had no effect on growth; no observable toxicosis was produced until 260 days; all fish in the group treated with the highest concentration died after 260 to 265 days. Thyroid activity, as measured by 72-hr thyroidal125I uptake, increased significantly. Thyroid activity in channel catfish fed Aroclors 1232, 1248, 1254, or 1260 at concentrations of 2.4 and 24Μg/g was altered only by Aroclor 1254.

Notizen: Abstract In a study of the degradation of phenolic compounds in a polluted part of the St. Lawrence River with normal concentrations of phenolic compounds varying between 10 and 150 ppb, it was found that the process could mainly be attributed to the action of microorganisms. On an average, 70% of the microflora in the river water was able to tolerate phenols at a concentration of 150 ppm. The number of phenoltolerating bacteria was found to increase from a relatively unpolluted to the most polluted part of the river by approximately 40%. Thirty-three strains of phenol-utilizing bacteria were isolated of which 31 were tentatively identified. Most of the strains belonged to the genera ofAchromobacter, Azotobacter, Bacillus, Brevibacterium, Clostridium, Flavobacterium, Micrococcus, Pseudomonas, andSarcina. After adaptation, many of these organisms could tolerate phenol concentrations as high as 2400 ppm, whereas most of them were able to decompose as many as 3 to 4 different types of phenols. The phenol decomposing microflora was subjected to seasonal fluctuations with regard to its composition, the tolerance of its members to different phenols and the temperature of optimum growth.

Notizen: Abstract Analytical grade 2,4,5-T and TCDD were dissolved in acetone and injected into the airspace of fertile chicken eggs. Toxicity studies suggest that the LD50 for 2,4,5-T is 133.1 mg of 2,4,5-T per kg of egg weight. The LD50 for TCDD was estimated to be 2.4 × 10−4 mg of TCDD per kg of egg weight. A partitioned chi-square analysis of the embryo viability data and the nonparallel dose response lines obtained from 2,4,5-T and TCDD suggest an independent mode of action for the two chemicals. As a result of the injection of these two chemicals, increased liver weight to egg weight percentages occurred. Liver weight enlargement as a result of elevated nucleic acid content was ruled out based on the following observations: (1) both RNA and DNA levels per gram of liver tissue were depressed and (2) treatment group RNA to DNA ratios remained the same as controls.

Notizen: Abstract Oxytetracycline-HCI (OTC) concentrations were measured in citrus leaves, fruit, and soil after applying OTC to soil as a drench. OTC was detected sporadically in low concentrations in leaves only during the first day after OTC applications and was not detected in fruit flavedo. Even after repeated drenches, OTC was not detected below 8 in. in the soil profile. Furthermore, OTC remained highly active in soil for at least 40 days and could still be detected in low concentrations one and a half years after the last OTC drench application. Adsorption of OTC varied with different soil types. Sandy soil (99.1% sand) had relatively little OTC adsorption capacity compared to less sandy soils (92–94% sand). OTC was inactivated in organic muck soil.

Notizen: Abstract Hematological changes and concurrent enzymatic activities in various tissues were determined in rats injected parentally with Iomex, a petroleum derivate and proposed weedicide. Among the hematological parameters studied only the differential leucocytic count showed significant alterations. This was indicated by a significant decrease in the number of lymphocytes and an increase in those of neutrophils. Significant differences were not observed in the levels of acid phosphatase, glutamic oxaloacetic, and glutamic pyruvate transaminase activities in brain and liver of the experimental group of animals.

Notizen: Abstract Four days after carbaryl-naphthyl-1-14C was mixed with soil from a field treated 6 months previously with 4 lb/A of the same insecticide, only 28% of the radiocarbon remained. Approximately 90% remained in soils with no history of pesticide applications. However, dissipation of the carbaryl-14C residues from the latter soils continued at a rather steady rate over a 120-day test period, whereas there was little dissipation after 4 days from the former. Consequently, the total14C-residue levels were about the same, 15 to 20% of applied, when the last samples were taken. Carbaryl,per se, was the only apolar14C-residue recovered from the soil and only small quantities, less than 2% of the amount applied, of extractable polar metabolites were encountered. Almost all of the terminal residues were unextractable from the soil with mixtures of acetone and water. Much of the loss of14C-residues from the soil was attributed to the liberation of14C-carbon dioxide as a result of microbial degradation of the naphthalene ring. Several fungal and bacterial isolates degraded carbaryl in the same manner as observed with soil incubations, but the rates of degradation were much slower.

Notizen: Abstract The effects ofin situ-produced oil shale retort water on the metabolism of various substrates was studied bothin vivo andin vitro. The induction observed in rats was classified as Type I due to an increase in metabolism of hexobarbital and ethylmorphine without subsequent increases in zoxazolamine metabolism. The maximal absorption of the cytochrome-P-450-CO complex was observed to be 450 mμ, also consistent with Type I inducers. Cytochrome P-450 levels were also significantly increased over controls.

Notizen: Abstract Experiments involving dietary toxicity and residue relationships of DDT, dieldrin, and endrin were conducted with short-tailed shrews. Dietary concentrations of DDT dissolved in vegetable oils were usually more toxic than diets containing comparable amounts of powdered DDT. Younger shrews, particularly females, were more tolerant of powdered DDT than older animals; yet, there were no conspicuous age differences in toxicity of DDT dissolved in oils. In comparison to other mammals, short-tailed shrews are not unusually sensitive to DDT, dieldrin, or endrin on the basis of two-week feeding tests. The influence of age and sex on toxicity of DDT, endrin, and dieldrin was sometimes more important than body weight. Of those shrews of the same age and sex that were fed the same dietary dosage, heavier shrews were more tolerant than lighter individuals; and, heavier shrews tended to lose a greater percentage of body weight before death. There was a range of 15 to 105 DDT equivalents in brains of shrews dying on dietary dosages of DDT. Six shrews fed a high level of DDT seemed to have unusual metabolite capabilities and died with apparent lethal levels of DDD in their brains. Levels of dieldrin in brains of shrews that died on a dietary dosage of dieldrin ranged from 3.7 to 12.6 ppm. In the rates of gain and loss experiments where shrews were given diets containing 400 ppm DDT or 50 ppm dieldrin up to 17 days, high residues were noted in tissues of shrews after two weeks on a contaminated diet and a few died at that time. After shrews were placed on clean food, it was determined that 〉50% of the dieldrin residues in carcass and brain were lost in 〈2 weeks. Males and females fed DDT for 17 days lost 〉50% of residues of DDT and metabolites in brains after 2 weeks on clean food; males lost nearly 50% of residues in carcasses after two weeks on clean food compared with a loss of only 11% in females.

Notizen: Abstract Endrin and malathion effects on survival, growth, and reproduction of flagfish were determined in a flow-through system. Endrin chronic effects on first-generation growth and reproduction occurred only at 0.3μg/L, the highest concentration tested. The mean endrin residues in the first-generation fish at 65 days were about 15,000 times the water concentration in all concentrations tested. Malathion concentrations of 31.5μg/L and 24.7μg/ L, the highest concentrations tested, had detrimental effects on first-generation survival. During the same period malathion concentrations as low as 10.9μg/L significantly affected growth. Neither insecticide, at the concentrations tested, had any detectable effects on the second generation during a 30-day exposure period. Acute toxicities to juvenile fish were also determined in the same flow-through system. The 96-hr LC50's were 0.85μg/L for endrin and 349μg/L for malathion.

Notizen: Abstract Arsenic concentrations were measured in aquatic invertebrates, macrophytes, sediments, and water of lakes in the vicinity of Yellowknife (N.W.T.), Canada. In arsenic-contaminated lakes the arsenic concentration ranged from 0.70 to 5.5 ppm in water, 6 to 3,500 ppm in bottom sediments, 150 to 3,700 ppm in macrophytes, 700 to 2,400 ppm in Zooplankton, and 〈1 to 1,300 ppm in other invertebrates. The arsenic concentration in invertebrates varied with sampling time, place, and taxon. Arsenic concentration factors were calculated, and found to decrease with increasing concentration of arsenic in ecosystem components of the lake. No evidence was found for biomagnification of arsenic through ascending trophic levels. In high-arsenic lakes herbivores had the highest arsenic concentrations, and omnivores the lowest. Pelecypoda, Ephemeroptera, Amphipoda, and Hirudinea were conspicuously absent from high-arsenic lakes. These particular organisms may be more susceptible to the effects of arsenic than others.

Notizen: Abstract Photothidiazuron-14C, a major photoconversion product of thidiazuron defoliant on cotton leaves, was rapidly absorbed and eliminated following oral administration to rats. By 96 hr posttreatment, 90.7% of the administered dose was accounted for in the urine (75.5%) and feces (15.2%). Between 5.0 and 10% of the radioactive material in the urine partitioned into ethyl acetate. In addition to photothidiazuron and several unknowns, the following metabolites were present: 4-hydroxyphenylphotothidiazuron, phenylurea, and 4-hydroxyphenylurea. There was also some evidence for the presence of 4-hydroxyacetanilide. The major portion of the radioactivity (〉90%) remained in the urine after extraction with ethyl acetate. Cleavage data withbeta-glucuronidase and aryl sulfatase indicated that at least 12.1% and 6.3%, respectively, of the urinary radioactive materials were conjugated with glucuronic and sulfuric acids. Compounds included 4-hydroxyphenylurea, 4-hydroxyphenylphotothidiazuron, and several unknowns. Fractionation of the feces indicated that about 10% of the radioactive material was organosoluble, about 20% was water soluble and about 70% was unextractable from the fecal residue. Tissue levels of radioactivity were low and in the ppb range.

Notizen: Abstract Several experiments were designed to examine the acute toxicity of surfactants toDaphnia. Specific tests were designed to develop comparisons between existing acute toxicity data for fish and similar data forDaphnia, and to provide data on the effects of various environmental factors on resultant toxicity of surfactants toDaphnia. Acute toxicity data for a series of homologous linear alkyl benzene sulfonates (LAS) demonstrate increases of up to one order of magnitude in toxicity for each increase of two alkyl carbons. LC 50's obtained withDaphnia magna are similar to those obtained with bluegills,L. Macrochirus. Comparative tests withD. magna andD. pulex indicate no statistical differences in 48-hr LC 50 values for three anionic and two nonionic surfactants. A 50 mg/L concentration of suspended, naturally-occurring kaolin significantly reduced the toxicity of longer chain length LAS homologs and had no effect on nonionic surfactant toxicity. In tests with variable hardness concentrations, the acute toxicity of LAS toD. magna is a combined function of both culture and test water hardness. The toxicity of a nonionic surfactant toD. magna was higher in soft water and was not affected by culture water hardness levels. Unlike previously published data for fish, the results of acute toxicity tests withD. magna cultures previously exposed to 0.4 mg/L LAS for periods up to seven generations indicated no significant difference in LAS susceptibility compared to simultaneously tested unexposed controls.

Notizen: Abstract The feasibility of decontaminating soil at parathion spillage or disposal sites by inoculation with a highly acclimated culture of parathion-degrading bacteria was demonstrated underin situ field conditions. The acclimated culture (AC), capable of utilizing parathion as a sole carbon and energy source, was inoculated into Yolo silt loam soil in which parathion was applied at rates up to 5000 kg/ha. The AC was shown to be capable of completely degrading parathion in soil containing up to 1250 kg/ha of parathion within 35 days. A slower rate of parathion degradation by the AC was observed when the pesticide was applied as the commercial 46.5% emulsifiable concentrate than when applied as the 98% technical grade. The ability of the AC to degrade parathion deteriorated at application rates greater than 1250 kg/ha. The AC may have been adversely affected by the accumulation of the parathion hydrolytic products,p-nitrophenol and ionic diethyl thiophosphate, which were tentatively identified in soil samples.

Notizen: Abstract Samples of commercial feeds for laboratory rats, guinea pigs, cats, monkeys, rabbits, and hamsters were collected and analyzed qualitatively and quantitatively for selected antibiotics, trace metals, pesticides (organophosphates and chlorinated hydrocarbons), natural agents, and polychlorinated biphenyls (PCBs). The results indicated that anitibiotics, parathion, diazinon, aldrin, and the aflatoxins were not detected, whereas, metals, chlorinated hydrocarbon pesticides (except aldrin), and PCBs were continually present. Malathion and estrogen were found occasionally.

Notizen: Abstract Juvenile starry flounder (Platichthys stellatus) and rock sole (Lepidopsetta bilineata) were force-fed 56 μCi each of 1-3H-naphthalene dissolved in salmon oil. Values for radioactivity associated with naphthalene and the metabolite fraction were determined for various tissues and body fluids. Results show that these pleuronectids extensively metabolize dietary naphthalene. The rates of decline in naphthalene concentrations (expressed as disintegrations per minute per milligram of dry tissue) were greater than the rates of decline in metabolite concentrations (dpm/mg) in liver, blood, and skin; therefore, relative proportion of metabolites to naphthalene increased with time and at 168 hr after the initiation of the naphthalene-exposure, more than half of the total radioactivity in both species of fish was associated with the metabolites. Profiles of metabolites in liver, skin, and bile were obtained using thin-layer chromatography. 1,2-Dihydro-1,2-dihydroxynaphthalene constituted 38.7 and 39.7%, respectively, of the total extracted metabolites in livers of the naphthalene-exposed rock sole and starry flounder at 24 hr, whereas the bile from both species contained primarily (〉90%) conjugates. From 24 to 168 hr, a significant (P 〈 0.05) decrease in the proportion of the dihydrodiol derivative and a concomitant increase in the proportion of conjugates—specifically, sulfate/glucoside fraction-were observed with livers of both rock sole and starry flounder. No significant change occurred in the spectrum of biliary metabolites with time. The pattern of metabolites in skin of both species was qualitatively similar to that in liver; however, the proportion of the dihydrodiol was greater in skin than in liver at 24 hr. When naphthalene (56μCi) dissolved in salmon oil was administered to starry flounder via intraperitoneal injection, the extent of biotransformation was less than after dietary exposure. Moreover, metabolites in the livers of the fish in the injection study were predominantly (76.7% of total extracted metabolites) non-conjugates at 24 hr. Once again, from 24 to 168 hr, an increase in the proportion of the sulfate/glucoside fraction and a concomitant decrease in the proportion of the dihydrodiol was observed with liver. These studies demonstrate that the extent of biotransformation of naphthalene and the types of metabolites remaining in tissues (e.g., liver) of flatfish are greatly influenced by both the mode of exposure and the time elapsed after the exposure is initiated. It appears therefore, that different exposures (e.g., in water, food, or sediment) of pleuronectids to polycyclic aromatic hydrocarbons may result in different degrees of alteration in genetic material because of variability in accumulation of non-conjugated metabolites, some of which are implicated in covalent binding with DNA in terrestrial mammals.

Notizen: Abstract Cadmium concentration inNereis virens exposed to sediment spiked with cadmium increased linearly with time, no equilibrium concentration being indicated by 24 days of exposure. The concentration withinN. virens also increased with concentration of Cd in the sediment, and smaller worms accumulated higher amounts per unit weight than larger worms. With exposure to sediment containing 1 to 4 ppm Cd, accumulation rates ranged from 0.018 to 0.037μg Cd/g dry wt/hr for 1- to 2-g worms and from 0.014 to 0.024μg Cd/g dry wt/hr for 5- to 7-g worms. N. virens exposed to 0.03 to 9.2 ppm Cd in sea water for 14 days had accumulation rates of 0.019 to 2.217μg Cd/g dry wt/hr for 1- to 2-g worms and 0.013 to 1.327μg Cd/g dry wt/hr for 5- to 7-g worms. There was practically no excretion of cadmium forN. virens with initial concentrations of 5 to 20μg Cd/g dry wt during 75 days in clean conditions. Sediment containing 1 and 4 ppm Cd produced concentrations of about 0.03- and 0.1-ppm cd in the overlying water. The accumulation rates from sediment with 1 and 4 ppm Cd are equal to the rates from sea water with 0.03 and 0.1 ppm Cd, respectively, indicating that cadmium uptake byN. virens is primarily from the aqueous phase.

Notizen: Abstract Selenium is an important essential nutritional trace element which has been shown to provide protection against certain other metal poisoning. However, it is a suspected carcinogen and teratogen. The uptake, depuration, and toxicity of selenium inDaphnia pulex have been examined. The LC50 at 48 and 96 hr for juvenile animals is 0.6 mg/L and 0.1 mg/L respectively, and for adults it is 1.3 mg/L and 0.5 mg/L respectively. Uptake in adult unfed animals is rapid, reaching a maximum at about 12 hr, but depuration is slow. In fed animals, uptake is slower, reaching a maximum at 96 hr, but initial depuration is followed by a slower prolonged loss. Localization in cells is primarily in the cytoplasmic compartment although evidence is presented which suggests nucleolar localization. Ultrastructural damage is detected by 16 hr after exposure and is initially confined to the mitochondria. Dense deposits accumulate in the mitochondrial matrices. The nature of these deposits is unknown; they may represent a calcium-or phosphate-selenium complex. With time, the mitochondria degenerate. It is clear that relatively low concentrations of selenium are toxic to these aquatic organisms and render them incapable of survival in the natural environment. Concentrations higher than those lethal toDaphnia can be expected, at least in local areas, from the burning or conversion of fossil fuels.

Notizen: Abstract Spectrophotometric measurements of the activities of some dehydrogenases and electron transfer complexes of isolated corn-shoot mitochondria revealed that N-(phosphonomethyl)glycine (PMG), a broadspectrum, non-selective, and post-emergence herbicide, at a concentration of 6.25 × 10−4M enhanced by about 10% the activities of NAD+-linked malate and NAD+-linked isocitrate dehydrogenases. At concentrations of 5 × 10−3M and 10 × 10−3M PMG, the activities of succinate and the NAD+-linked dehydrogenases were reduced by at least 10% and 25%, respectively. Although no effect was observed on the activities of the electron transfer complexes at lower concentrations of PMG, these enzymes were inhibited by at least 10% and 20%, respectively, at 5.0 × 10−3M and 10 × 10−3M PMG.

Notizen: Abstract Medicago sativa L. (Leguminosae) sprayed withO,O-dimethylS-(N-methylcarbamoylmethyl) phosphorodithioate (dimethoate) had only 0.5 ppm of dimethoate in pollen one day later, but 3 ppm in nectar one week later, and 1 ppm in nectar two weeks later. As little as 1 ppm added to syrup fed to caged workers ofApis mellifera L. (Apidae) inhibited cholinesterase and reduced survival. Bees given a choice between treated and untreated syrups showed no preference; this suggests that the levels of dimethoate found in nectar are toxic and not repellent.

Notizen: Abstract The effect of DDT on growth and DNA synthesis inStylonychia notophora was investigated. DDT at a concentration of one ppm did not alter the cell population growth and the morphology of the organisms. However, 50 and 100 ppm DDT inhibited growth and cell division. Continuous treatment of the organisms with 100 ppm DDT produced several nuclear abnormalities. Cells treated with 100 ppm DDT in G1 did not enter S-phase while DNA synthesis was blocked in those cells treated in S-phase.

Notizen: Abstract Sublethal exposure of juvenile coho salmon (Oncorhynchus kisutch) to Cr (as sodium dichromate) in freshwater decreased their disease resistance and serum agglutinin production againstVibrio anguillarum. Duplicate disease resistance experiments, in which groups of salmon were exposed to 0.0 or 0.5 mg Cr/L for two weeks and then injected in subgroups with one of four tenfold dilutions of liveV. anguillarum (ca. 3–4 × 102–5 bacteria/.1 ml dose), showed that disease mortality increased with dose and was significantly greater in Cr-exposed fish. Serum agglutinin production, measured in fish which were injected withV. anguillarum bacterin and then exposed to 0.0 or 0.5 mg Cr/L for two weeks, was significantly inhibited in Cr-exposed salmon by six weeks after immunization. It is suggested that measurement of disease resistance and agglutinin production may be sensitive and ecologically realistic indicators of sublethal toxicity in aquatic animals.

Notizen: Abstract Behavioral effects of toxaphene, and its toxic components, toxicant A and toxicant B, were studied by perinatally exposing juvenile rats. Toxaphene was given daily to pregnant rats (and their offspring) at 50μg/kg body weight via their diet. The daily dietary levels of toxicants A and B were 2.0μg/kg body weight. Behavioral tests were performed on the off-spring. All rats fed toxaphene, as well as toxicants A and B, showed retarded maturation as judged by the swimming test during their early development. However, the treated rats eventually attained normal swimming ability. The maze retention test demonstrated significant differences between the toxicant A group and all other groups. The toxicant A animals had no difficulty in learning the test problems but were inferior to the other groups in retaining that knowledge.

Notizen: Abstract Degradation of14C-ring labeled atrazine (2-choloro-4-(ethylamino)-6-(isopropylamino)-s-triazine) by bacterial populations from soil, waters and activated sludges was investigated and compared with non-biological decomposition in sterile solutions. Within two weeks, 0.6% Cl-deethyl- and 0.1% Cl-deisopropylatrazine had been formed in sterile 0.02 M phosphate buffer, pH 7.2. In biodegradation studies, bacterial populations were enriched and incubated in media containing atrazine and high or low levels of nutrients. Nutrient supply had a strong effect on the fate of atrazine in bacterial cultures, whereas the origin of bacteria was of minor importance. In 31 of 33 mixed populations investigated, the herbicide was largely converted to unidentified compounds. Incubation with high levels of nutrients resulted in 17% to 57% of these compounds being constant after one and two weeks of incubation. In parallel experiments with low nutrient supply, the compounds were present in amounts of 7% to 57% after one week. The proportions of the unidentified compounds dropped within the second week of incubation, while atrazine reappeared correspondingly. The amounts of dealkylated metabolites generally did not exceed those of sterile solutions. The results indicate that atrazine is not degraded by bacteria but bound, thus simulating biodegradation. Evidence is presented that physicochemical decomposition of the herbicide is more significant than microbial degradation.

Notizen: Abstract Lead was administered to adult male rabbits in drinking water at a 0.1% concentration for four and five week periods. The lead contents were determined in the central and peripheral nervous tissues and in the liver, kidney, and intestinal mucosa. The conduction velocity of sciatic nerve and the activities of drug metabolizing enzymes in other tissues were determined. The lead concentration in the blood was at a steady state at four to five weeks of exposure. Lead accumulated in all tissues except the brain. The brain lead concentration was 40 to 50% of that in the blood, indicating the existence of a blood-brain barrier. However, the lead concentration in the sciatic nerve increased significantly from four to five weeks of exposure and exceeded that in the blood. This indicates the lack of a blood-nervous tissue barrier in the sciatic nerve allowing a continuous accumulation of lead. This accumulation affected the function of the sciatic nerve; motor nerve conduction velocity decreased from the control level (58.3±7.4 m/sec) to 43.8±6.3 m/sec after the four-week exposure and to 35.0 ± 1.3 m/sec at 5 weeks of exposure. After five weeks of exposure, no changes in the hepatic, intestinal, or renal drug metabolizing enzyme activites were found. These results suggest that motor nerve conduction velocity is affected by lead exposure prior to any influence on biotransformation enzymes.

Notizen: Abstract The chronic effects of hexavalent chromium on the fathead minnow (Pimephales promelas) were investigated. Survival was affected only at the high test concentration of 3.95 mg Cr/L. All chromium concentrations, including 0.018 mg/L, the lowest tested, retarded the early growth of first-generation fish, but this effect was only temporary. Growth of second-generation fish was not affected at concentrations of 1.0 mg/L or lower. Reproduction and hatchability of eggs were not affected at any chromium concentration tested. The maximum acceptable toxicant concentration (MATC) for fathead minnows in hard water (209 mg/L as CaCO3 at pH 7.7) was based on survival and lies between 1.0 and 3.95 mg Cr/L, respectively. The application factor (MATC/96-hr LC50) is between 0.03 and 0.11.

Notizen: Abstract Cadmium (Cd), copper (Cu) and zinc (Zn) contents in 116 polished and unpolished rice samples produced in the Java Islands of Indonesia were assessed as a base-line study of trace metals. Arithmetic means and one standard deviation were 0.040±0.042 ppm Cd, 2.93±1.11 ppm Cu, and 18.17±3.13 ppm Zn. Concentration ratio of Cd to Zn was 0.00220±0.00222. The correlation coefficients between the metals were low. The two highest samples of rice contained 0.27 and 0.34 ppm Cd. Using the fact that Indonesians consume about 300 g of rice, the daily intake of Cd would exceed the tolerable limit proposed by FAO/WHO and could cause slight chronic renal damage to the rice eaters. Soil type by suborder and rice variety gave little difference of the three metals content in rice. Rice samples from West Java, where major soil type by order is Ultisol, contained higher cadmium and zinc, and lower copper than those from East Java (Vertisol).

Notizen: Abstract Specimens of a fresh water fish,Notopterus notopterus were exposed to either phenol (12.56 mg/L), dinitrophenol (1.34 mg/L), or a mixture of the two (6.28 mg phenol + 0.67 mg dinitrophenol/L) for 72-hr. Surviving fish were sacrificed at 24-, 48-, and 72-hr after exposure, and tissue samples were taken for determining the acid phosphatase and alkaline phosphatase activities. Phenol, dinitrophenol, and mixtures of both, inhibited the activity of both enzymes in the kidney, heart, brain, gills, muscles, stomach, intestine, and pyloric caeca. Dinitrophenol exerted more inhibition than phenol. In general, mixtures of phenol and dinitrophenol are somewhat more effective than either compound alone in the inhibition of enzyme activities.

Notizen: Abstract The reproducibility, variability, and reliability of a simple aquatic-terrestrial model ecosystem experiment was tested withp,p′-DDT. The variation among the model replicates as well as within the units was studied by using hierarchal analysis of variance. The complete budget of the chemical was calculated and a theoretical transport model was constructed. The degradation and accumulation of DDT was followed by gas Chromatographic residue analysis, which showed good reproducibility of the experimental design. The degradation of DDT in the model was similar to that found in the field, but the determination of concentration factors was questionable. The material balance tables revealed that the soil and bottom substrates were the main contributors, which regulated the fate of the chemical in the model. The usefulness of the model is presented in this report.

Notizen: Abstract The acute and embryo-larval toxicity of the Laramie Energy Technology Center's Hanna-3 underground coal gasification (UCG) condenser water and its constituents were studied in continuous-flow bioassays. The 96-hr LC50 dilution values for untreated Hanna-3 UCG condenser water were 0.1% for rainbow trout, 0.11% for fathead minnows and the 48-hr LC50 dilution forDaphnia pulicaria was 0.18%. Separate 96-hr acute tests with phenol, ammonia, and ammonia plus phenol showed that these two constituents, acting synergistically, were the major constituents affecting the acute toxicity of this coal conversion effluent to fishDaphnia pulicaria, on the other hand, was relatively insensitive to phenol exposure; the primary constituent of Hanna-3 UCG condenser water affecting this species was ammonia. A previously described model was used for predicting the toxicity of effluents with high concentrations of phenol and ammonia to confirm our hypothesis that the acute toxicity of Hanna-3 UCG condenser water to fish was primarily due to the presence of phenol and ammonia. Using the Hanna-3 concentrations of phenol and ammonia in this formula, it was calculated that the 96-hr LC50 values for rainbow trout and fathead minnows exposed to Hanna-3 condenser water would be 0.11% and 0.28%, respectively; values which are near the observed acute toxicity of Hanna-3 condenser water. In a 30-day embryo-larval exposure, fathead minnow egg hatchability, growth, and survival were significantly reduced at 0.04%, 0.02% and 0.01% Hanna-3 condenser water, respectively. At a Hanna-3 dilution of 0.01%, the phenol and un-ionized ammonia concentrations were calculated to be 0.23 mg/L and 0.14 mg/L, respectively. The phenol and un-ionized ammonia concentrations are within ranges expected to produce the long-term effects which were observed.

Notizen: Abstract The isolatesAcinetobacter spec., Cytophaga spec. andPseudomonas fluorescens represent different morphological and physiological types of bacteria. They accumulate atrazine (2-chloro-4-(ethylamino)-6-(isopropylamino)-5-triazine) to different levels. Accumulation expressed by the ratio of atrazine sorbed per volume of bacteria to atrazine per the same volume of water amounted to 11 forAcinetobacter spec., 8.6 forCytophaga spec and 6.2 forPseudomonas fluorescens. Accumulation ratios were proportional to the surface areas of the organisms. Single cells ofAcinetobacter spec. sorbed amounts of atrazine comparable to the other species investigated, whereas cell aggregates, formed a few months after isolation, sorbed an order of magnitude less. A large portion of atrazine accumulated by the bacteria could be rapidly desorbed. A remainder of 10% was bound byCytophaga spec. andPseudomonas fluorescens. Acinetobacter spec. bound 70–80% of the atrazine sorbed. In the range of 0.3–3 mg/L atrazine, there was a linear relationship between the amount of non desorbable herbicide and its concentration in the incubation medium.

Notizen: Abstract Experiments were performed on the accumulation of the pesticide lindane (γ-isomer of BHC) by two algae with different surfaces. An analytical procedure was developed for the gas Chromatographic determination of lindane. At room temperature, lindane had a water solubility of 7.8 mg/L in distilled water and 6.7 mg/L in tap water. Under the experimental conditions of 10 to 100μg/L, 2.3% of the dissolved lindane was lost through adsorption on the glass walls of the equipment and 0.2% through evaporation. The recovery rate of lindane was 98% for the water samples and more than 90% forChlorella spec. The tolerance in the gas Chromatographic measurements amounted to 1.2%. Investigations on the effect of lindane on the growth ofChlorella spec. revealed irreparable damage to the algae cells through loss of chlorophyll, coagulation, and complete sedimentation at concentrations greater than 300μg/L. The experiments on sublethal accumulation showed the development of a state of equilibrium between the amount of lindane per cell and in the surrounding water with lindane concentrations of 10 to 100μg/L. The lindane was adsorptively attached to the algal cells within a few hr, and after three days lindane stabilized in the cells. The gelatinous surface of the algae increases the accumulation of lindane.

Notizen: Abstract Juvenile male chickens were exposed continuously to 300μg/ml of mercury (Hg) in the form of mercuric chloride (HgCl2),via the drinking water, from hatching through six weeks of age. Serum osmolality and plasma potassium were increased significantly as a result of the Hg treatment. Plasma sodium was increased numerically in two of the three trials. Of the serum proteins, only albumin and the transferrins exhibited a consistent significant increase. It is concluded that alterations in serum ions and proteins account for the significant increase in plasma osmolality. The increase in transferrins may represent a mechanism to bind and detoxify Hg.

Notizen: Abstract The physiologic response of 21 male agricultural field workers exposed to foliage-borne Guthion residues was monitored during routine peach-thinning operations in a northern California orchard. Surveillance included daily venipuncture and urine collection to determine whole blood cholinesterase (CHE) activity and level of dialkylphosphate excretion for 3 baseline (nonexposed) and 5 normal work days. Foliage samples were obtained to measure dislodgeable and total Guthion residues. A decrease in group-mean CHE activity by 15% over the surveillance period was found. Apart from one worker who showed a consistent decrease in CHE activity, reaching a maximum of 30% below baseline at the end of the work week, daily changes in individual CHE activity were erratic. Group-mean dialkylphosphate excretion levels provided a semiquantitative indication of exposure to Guthion. Medical examination before and after the exposure period revealed an absence of clinical signs of organophosphate intoxication.

Notizen: Abstract After the environmental contamination by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in the area of Seveso, Italy, thousands of small domestic animals (mainly rabbits and poultry) died within a few weeks. Autopsies on dead animals showed various pathological signs, such as hepatic lesions and haemorrhage. TCDD was monitored in animal tissues by gas chromatography-mass fragmentography; rabbit liver levels corresponded fairly well to soil contamination, which indicated that this species can be used as a tool for tracking the presence of TCDD in the environment.

Notizen: Abstract Male rats were fed diets containing 0, 1, or 5 ppm parathionad libitum for 28 days. Three other groups of rats were fed diets containing 0, 2, or 10 ppm parathion for 28 days but were fed only 50% of the food intake of the correspondingad libitum groups. Effects on plasma cholinesterase activity and plasma and liver carboxylesterase activities were observed in the 5 ppm and 10 ppm parathion groups. Food restriction increased the inhibition elicited by parathion with each of these parameters. No significant inhibition of brain cholinesterase by parathion alone or with food restriction was observed. Lesions of the pancreas were noted in animals receiving 10 ppm of parathion and subjected to 50% normal food intake.

Notizen: Abstract Metabolic fates of14C-toxaphene and two of the toxic components of toxaphene were studiedin vitro by using rat liver enzyme preparations. The enzyme systems involving toxaphene metabolism were characterized, using known cofactors and inhibitors to activate or inhibit individual enzyme reactions. The nature of toxaphene metabolites was studied through derivatization of metabolic products via chemical and enzymatic treatments. The results of thein vitro studies were compared to the metabolic patterns observedin vivo to ascertain the relative importance of each enzyme system in the total process of toxaphene degradation and excretion.

Notizen: Abstract The fire-ant poison, Mirex, was administered via stomach tube (dosage 200 mg/kg) to 50 adult Mai-Wistar male rats and the resultant histopathologic lesions produced in their livers after six days post-intubation are described. Light (LM) and electron microscopic (EM) technques revealed cellular and subcellular alterations in response to this sublethal dosage. Pathologic lipid accumulations occurred in Mirex-exposed rats and this fat appeared in a distinctive periportal zonation pattern. Additional lesions were detected in centrolobular zones with the EM and included severe glycogen depletion, altered regularity in the architecture of rough or granular endoplasmic reticulum (GER), dilated GER cisternae, free ribosomes, and proliferation of smooth endoplasmic reticulum. Periportal hepatocytes exhibited apparent reduction in numbers of cytoplasmic organelles and development of many, large lipid-containing vacuoles. Myelin figures were sometimes associated with developing lipid (liposomes), suggesting a contribution of myelin membranes to the developing lipid droplets or vice versa. Biochemical studies revealed that glycogen levels dropped markedly, lipid content greatly increased, and protein/DNA and RNA/DNA values decreased.

Notizen: Abstract Metallothioneins with differing Cd/Zn ratios were preparedin vitro from rat liver zinc-thionein by replacing zinc with cadmium and were injected intraperitoneally to female rats. The distribution of cadmium, zinc, and copper in the kidney supernatant fraction was determined using a Sephadex G-75 column. The distribution pattern of cadmium and zinc changed dramatically within 24 hr after the injection. The changes were explained by the degradation and re-synthesis of metallothionein in the kidneys. The necrotic changes of renal tubular lining cells were correlated to the amount of cadmium in the metallothionein but not to the amount of metallothionein (protein).

Notizen: Abstract Three experiments with a sabellid polychaete (Eudistylia vancouveri) show the threshold concentration for increasing copper accumulation with time to lie between 3 and 6 μg/L total copper in seawater during winter conditions. The branchial crown, probably the major absorptive site, concentrated more copper than the body. Accumulation was influenced by size but not by sex. Our studies indicate that the body burden of copper will increase above natural levels in areas of industrial discharge where copper levels are above the threshold limit for accumulation.

Notizen: Abstract The average amounts of mercury, PCBs, and σ DDT (primarily DDE), found in macrozoobenthos, on the wet basis, in Lake Päijänne, Finland, for the time period 1972–1974, were 79 ng/g, 29 ng/g, and 8 ng/g, respectively. Lindane was found in negligible amounts in only 2% of the samples examined; aldrin was present in 10% of the samples; no dieldrin was detected. Mercury and PCB concentrations varied regionally in the lake. PCB and σ DDT concentrations were greater in the predatory bottom animals than in the herbivores or detritus feeders, and the amounts of chlorinated hydrocarbons were greater in profundal animals than in littoral animals. No significant correlation was apparent between the amount of residues found and the weight of the animal (e.g.Anodonta). A significant positive correlation was evident in the amounts of PCBs and Σ DDT in most of the taxonomical groups.Spongilla lacustris andAnodonta piscinalis were excellent species for monitoring purposes.

Notizen: Abstract Plasma and red blood cell cholinesterase levels of professional agricultural workers engaged in packing sweet corn and thinning peaches were monitored. Workers with extensive contact with mechanically harvested sweet corn (the corn had been treated one or two days before harvest with a combination of ethyl and methyl parathion) exhibited significant depression of cholinesterase. Gloves, worn by 40% of the workers, provided some protection from absorption of pesticide residues. No significant cholinesterase depression was found in workers thinning peaches which had been previously treated with parathion.

Notizen: Abstract This study describes the extent of DDT contamination in a typical fruit growing district in Norway two and four years after the DDT ban. Residues of DDT in man, dairy cows and soil were about five to one hundred times higher than in the control groups, while residues found in samples from the marine biota were the same or moderately higher (Figure 3). The residues of DDT in cows, gulls and parts of the marine samples showed a significant decrease from 1972 to 1974, while the level in soil was almost constant. The amount of DDE had increased considerably in 1974 for all the species except for the gull, although not to the same degree. The distribution of DDE, DDD and DDT in soil were almost constant during the two years of sampling.

Notizen: Abstract Channa punctatus were exposed to various sub-lethal concentrations of Idet 5L and Swanic 6L for 25 and 50 days. Brain and gill homogenates were analyzed for enzyme activity from treated and untreated fish. Enzyme inhibitions were highest in oligomycin-insensitive Mg++ ATPase, with pronounced effects (over 65% inhibition) after 50 days exposure of fish to 7.5 mg/ L concentration of Swanic 6L. Fish exposed to lowest concentrations of syndets showed an insignificant activation of Na+-K+ and oligomycin-sensitive Mg++ ATPases in the gill.

Notizen: Abstract Acute toxicity tests showed that selenium dioxide was a strong antagonist against mercuric chloride toxicity in goldfish. Paradoxically, whole body accumulations of total mercury were found to be significantly increased with the administration of Se. Maximum binding of Hg to fish was produced by approximately equimolar experimental concentrations of Hg and Se, but higher levels of Se reduced this binding. The greater the Hg accumulation the greater was the ability to survive a given environmental Hg concentration. Much of the Hg was in the skin and surface mucus on the gills and body; however, Se also increased Hg concentration in the inner tissues of the fish.

Notizen: Abstract The retention properties of PCBs (polychlorinated biphenyls) were examined in the mussel (Mytilus edulis) over a period of 89 days. Mussels were transferred from a site of relatively high PCB contamination to a site of relatively low PCB concentration in Puget Sound, Washington. Retention of PCB components increased with increasing chlorine content. Concentrations of PCB decayed logarithmically with calculated half-lives ranging from 3 days for a PCB component with two and three chlorines to 50 days for a PCB component with six and seven chlorines. Components chosen to best represent the commercial PCB mixtures, Aroclor® 1242, 1254, and 1260, were estimated to have half-lives of 8, 23, and 39 days, respectively. The selective retention of the higher chlorinated biphenyls appear to be the result of lower water solubility of these components.

Notizen: Abstract An acute lethal dose (1.7 g/kg body wt) of3H-labeled 2,5,2′,5′-tetrachlorobiphenyl (TCB) given to rats produced swollen hepatocytes that had conformationally altered mitochondria, a large degree of intracellular vacuolization, membrane fragmentation, particularly involving the rough endoplasmic reticulum, and an increase in cytoplasmic matrical material. The high specific radioactivity (dpm/mg protein) found in the plasma membrane (PM), as compared to other subcellular fractions, was correlated to decreases in the membrane-bound (Ca2+-Mg2+)-ATPase and Mg2+-ATPase activities. The radioactive material bound to plasma membranes or endoplasmic reticulum (ER) was organic-soluble and co-extracted with membrane lipids. No water-soluble metabolite conjugates were detected in these membrane fractions. In the cytosol, the majority of the radioactive material also was organic-soluble, with only 4% of the total radioactivity being water-soluble. The organic-soluble radioactive material associated with PM, ER, and cytosol was analyzed by thin-layer chromatography and mass spectrometry, and 78% of it was found to be unconjugated monohydroxy-TCB. These data suggest a possible relationship between inhibition of plasma membranelocalized ATPase and swelling of hepatocytes during the acute TCB intoxication. In addition, the membrane lipid-bound monohydroxy metabolite may be a factor contributing to the acute hepatotoxicity of TCB.

Notizen: Abstract The distribution and retention of atrazine and carbofuran in farm ponds were examined after application of 0.3 ppm of atrazine [2-chloro-4-(ethylamino)-6-(isopropylamino)-S-triazine] for two years and 0.025 ppm of carbofuran (2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate) the first year and 0.050 ppm for the second year. Samples of water, mud, and various biological components for the systems were collected periodically for residue analyses by gas chromatography. Soon after atrazine was applied, it was found in all physical and biological components. No biological magnification was observed. Carbofuran showed up only in the water and mud immediately after application; from then on it was absent from all components. No adverse effects from either pesticide were observed in the biological components.

Notizen: Abstract The red blood cell and plasma cholinesterase (ChE) levels of cotton scouts inspecting foliage for insect infestation and damage were monitored. Group means for ChE activity were significantly depressed at one or more time(s) during four of the eight growing seasons studied. Although no symptoms of organophosphate poisoning were confirmed, several scouts exhibited ChE depressions over 50% of pre-exposure levels.

Notizen: Abstract Six reforestation areas were sprayed with 2,4,5-T esters. Leaf samples from the areas were analyzed for the esters, tetrachlorodioxin, and dehalogenated phenoxyacetic acid esters. Tetrachlorodioxin was found in one leaf sample only, but the level found, relative to the amount of 2,4,5-T ester found, was lower than in the formulation material used in the study. The concentration of the dichlorophenoxyacetic acid esters present in several leaf samples was greater, relative to the 2,4,5-T ester, which indicated a photochemical breakdown of the 2,4,5-T in the environment.

Notizen: Abstract CrayfishCambarus latimanus were subjected over a 5-month period to 0.02, 5, and 10μg Cd/L in a continuous flow system at ambient winter temperatures. Uptake of cadmium, growth, and mortality were measured. One-half of the surviving crayfish were analyzed for Cd after completion of the 5-month experiment, while the remaining half were removed from the contaminated water and subjected in a static laboratory experiment to stepwise, daily increases in temperature. The results indicated that (1) the rate of Cd uptake in crayfish was positively related to external concentration, (2) mortality increased significantly with higher Cd concentrations, and (3) neither growth nor thermal tolerance was significantly related to the Cd concentration in the crayfish tissues. The importance of chronic, low-level studies is discussed.

Notizen: Abstract Serial levels of fireMaster® FF-1, a commercial mixture of polybrominated biphenyls (PBB), and tissues from chickens and a cow that had previously consumed PBB were fed to mink to ascertain the chronic effects of the commercial and “metabolized” form of this compound on mink. Diets that contained 6.25 ppm (or more) PBB were lethal to adult mink within 10 months. One to 2.5 ppm dietary PBB fed for 9 months had an adverse effect on litter size, kit weight at birth, and kit survival. The data suggest that the PBB derived from contaminated beef and poultry was more toxic than the original PBB. The clinical signs of PBB poisoning in mink were food rejection, weight loss, an unthrifty appearance, and fatty infiltration of the liver. Based on these findings, mink must be considered highly susceptible to PBB toxicity. PBB residue levels 60 times the amount in the diet were found in the adipose tissue of the PBB-treated animals.

Notizen: Abstract A laboratory chronic toxicity test in which bluntnose minnows were exposed to copper in laboratory dilution water with a hardness of 200 mg/L as CaCO3 indicated that copper adversely affected fry survival, fry growth, and reproduction. The maximum acceptable toxicant concentration (MATC) for total copper based on reproductive impairment at 18.0 μg/L was between 4.3 (control concentration) and 18.0 μg/L. The 96-hr LC50 values from three acute toxicity tests ranged from 0.22 to 0.27 mg/L total copper with a mean value of 0.23 mg/L. The application factor (MATC/96-hr LC50) for bluntnose minnows and total copper was estimated to lie between 0.02 and 0.08. Bluntnose minnows held in control water for nine months ceased to spawn when they were exposed to 119.4 μg/L total copper. Fish exposed to 119.4 μg/L total copper for the same nine-month period began to spawn 60 days after being transferred to control water.

Notizen: Abstract The response of embryos and larvae of the American oyster,Crassostrea virginica, to copper at various salinity-temperature regimes was studied in the laboratory using response surface methods and factorial analysis. The experimental design was a 3 x 3 x 4 factorial experiment using temperatures of 20, 25, and 30°C, and salinities of 17.5, 22.5, and 27.5 ‰ It was carried out at copper concentrations of 0, 5, 10, and 20 ppb for the embryos and 0, 30, 60, and 90 ppb for the larvae. Statistical analysis indicated that salinity had the greatest effect on the embryos at 0, 5, and 10 ppb copper, but temperature had as great an effect as that of salinity at 20 ppb copper. The capacity of the embryos to adapt to the temperaturesalinity changes was impaired when exposed to 20 ppb copper, as indicated by the shifting of the response center. Temperature had the greatest effect on the larvae when exposed to 30, 60, and 90 ppb copper. The interaction between temperature and salinity was significant only at the higher levels of qopper. Low levels of copper may produce intolerable stress upon the recruitment of oyster embryos during periods of persistently low salinities and low or high temperatures.

Notizen: Abstract Aquatic weeds from Cayuga Lake in New York were included as 10% or 20% dry weight of rations which were fed to growing pigs for 69 days. The animals gained weight at a rate comparable to those on a basal diet or a diet in which an equivalent weight of alfalfa replaced the aquatic plants. The feed efficiency (kg ration consumed/kg wt gained) of the aquatic rations was significantly lower, probably because of the lower nutritive value of the aquatic plants. Polychlorinated biphenyls (PCBs) were found in the aquatic plants (0.59 ppm, dry weight) and in the pig fat of those fed the aquatic ration. Hepatic microsomal mixed function oxidase activity was not significantly different in the animals fed the various treatment rations. Histopathologic examination of animal tissues revealed no lesions or abnormalities which could be attributed to the diets.

Notizen: Abstract The effect of the application of a group of pesticides (Temik®, Stomp®, Dinoseb, Nata®, Dursban®, and Simazine 1 on N2-ase activity in Giza clay-loam soil under maize cultivation was investigated in the presence of 1 to 2% glucose or malate amendments. Field concentrations of all pesticides showed different inhibitory effects, and the effects increased with increased doses (10-and 100-fold) and incubation period (11 days). Temik and Stomp more seriously inhibited N2-ase activity than Dinoseb and Nata; Simazine and Dursban had the lowest effect. The effect of the field dose of Stomp on the patterns of N2-ase activity and development of N2-fixing spirilla and azotobacters in soil amended with glucose or malate was followed for a period of one month. Inhibitory effects on N2-ase activity as well as numbers of asymbiotic N2-fixers were marked during the first week of incubation, followed by a step wise recovery to normal levels by the end of the experiment. The deleterious effect of the tested pesticides was repeated in pure cultures of certain isolates of N2-fixing spirilla and azotobacters.

Notizen: Abstract In this investigation, an evaluation was made of the lethality of a suspended clay mineral texturally representative of the sediment-size fraction with which contaminants are most commonly associated. The study involved a phylogenetically diverse selection of marine and estuarine macrofauna. The time-concentration mortality response of 16 species of fish and invertebrates indicated widely differing sensitivities to high concentrations of clay suspended in the water. Organisms restricted to muddy bottoms were found to be very insensitive to high suspended clay concentrations. However, some open water fish, fouling organisms, and sandy bottom epifauna were found to be relatively sensitive. Tolerant species were also identified from these groups.

Notizen: Abstract Inhalation exposure of male rats at three dose levels (4.2, 21, 62 mol/L) ton-heptane vapor caused a dose-dependent brain and body solvent burden, which increased during two weeks of exposure. Initial neurochemical effects included reduced RNA concentration and increased NADPH-diaphorase in brain at the lowest dose. Increased proteolysis was detected in the cerebral samples in the second week at all doses, and the NADPH-diaphorase returned to the control range. Brain RNA content tended to be larger than in the controls. All biochemical effects were abolished after two weeks of withdrawal from the two-week exposure, with the exception of reduced glutathione at the lowest dose. None of the rats presented clinical signs of neuropathy, which indicates that heptane and its metabolites do not share the specific neurotoxicity of hexane and its metabolites.

Notizen: Abstract Comparative findings are presented on the health and exposure status of groups of individuals in Hawaii with and without occupational exposure to pentachlorophenol (PCP). Occupational exposure to PCP occurred through employment at firms engaged in the treatment of wood with either PCP alone or PCP plus other compounds as preservative chemicals. Mean serum levels were 0.32 ppm for 32 control individuals, 1.72 ppm for 24 workers exposed to PCP and other wood preservative chemicals, and 3.78 ppm for 22 workers exposed to PCP as the sole preservative chemical. Age-standardized prevalence rates were significantly higher among the PCP-exposed than among the controls for low-grade infections or inflammations of the skin and subcutaneous tissue, protective membrane of the eyes and the mucosa membrane of the upper respiratory tract. Strong to moderate statistical associations were observed between PCP exposure and increased occurrence of bands (immature leucocytes) and basophils, increased plasma cholinesterase, alkaline phosphatase, gamma globulin and uric acid, and decreased serum calcium. Despite these statistical associations, laboratory values considered to be clinically abnormal were few and not significantly greater in occurrence among the PCP-exposed individuals.

Notizen: Abstract Uptake rates of total14C in fathead minnows (Pimephales promelas) exposed to sublethal concentrations of radiolabeled test compounds followed the order: phenol 〉 2,4,5-trichlorophenol 〉p-nitrophenol. Mean whole body14C concentration factors were 15,800, 1,850, and 180 for phenol, 2,4,5-trichlorophenol, andp-nitrophenol exposures, respectively. Only minor amounts of tissue14C was parent compound after 28 days of exposure in fish exposed to phenol andp-nitrophenol, while 78.6% of the14C was parent compound in 2,4,5-trichlorophenol exposed fish. Tissue14C in fish exposed to 2,4,5-trichlorophenol was eliminated at a faster rate than in fish exposed to phenol orp-nitrophenol. Observed mean14C depuration half-lives for lower and higher exposures combined were 387, 150, and 12 hours for phenol,p-nitrophenol, and 2,4,5-trichlorophenol, respectively. Parent compound comprised 1.5, 2.7, and 0.7% of total14C for phenol, 2,4,5-trichlorophenol, andp-nitrophenol, respectively, after 28 days of depuration. The percentage of acetone-unextractable14C increased from the end of uptake to the end of depuration for phenol and 2,4,5-trichlorophenol, and decreased slightly forp-nitrophenol.14C contribution from polar metabolites increased relative to total14C during the depuration phase for 2,4,5-trichlorophenol andp-nitrophenol.

Notizen: Abstract The body burdens of five organochlorine compounds were determined in several marine fishes and invertebrates from two localities in Norway. DDE, PCBs, and pentachlorobenzene showed uniform levels, especially on a fat weight basis, while hexachlorobenzene and octachlorostyrene were detected at various levels in the different species. The results are discussed with respect to the concept of accumulation through food chains, and passive partition of chemicals between water and the organism's fat. Although the results to some extent support the idea of partition, other factors may have a decisive effect on the levels found in the different species. This is true for the bottom dwellers, where magnitude and circumstances of exposure may vary considerably between the different microenvironments.

Notizen: Abstract The cytotoxic effects of sodium selenite on developing tadpoles (Xenopus laevis) were examined by scanning, light, and electron microscopy. Selenium exposure resulted in disorganization, vacuolization, and swelling of the outer layer of epithelial cells in the tadpole epidermis. Examination of muscle cells in the somites revealed myofibril disorganization and cell degeneration. Mitochondria in both epithelial and muscle cells were swollen and showed loss of cristae. It is likely that sublethal exposures to selenium compounds result in cellular damage which could affect motility, and thus survival, over longer periods of time.

Notizen: Abstract Tanytarsus dissimilis (Johannsen) was exposed to four heavy metals. Static exposure began during embryogenesis and continued through hatching and larval development to the 2nd or 3rd instar. The LC50 concentrations for cadmium, copper, and zinc were 3.8, 16.3, and 36.8μg/l, respectively. The LC50 for lead was 258μg/1. Growth was not reduced at exposure concentrations less than the LC50. The LC50 concentrations obtained in this insect exposure are as much as 1,600 times lower than other insect exposures reported in the literature. This is probably due to a combination of exposure of this insect during important life cycle events and species-specificity.

Notizen: Abstract Exposure to vanadium (V), which is a toxic element widely distributed in nature, is of increasing concern because of its occurrence in various fossil fuels. The distribution of V in selected tissues of male Swiss-Webster mice was investigated at different time intervals following a single intraperitoneal dose of two mg V/kg. The highest amounts of V were observed in the kidney at one day, whereas after one day, bone showed the highest levels of all tissues. Levels of V in liver were equal to those in the kidney at two days after the administration but were significantly higher than kidney after this period. In most tissues, there was a rapid decline of V residues, which was not necessarily log-linear in fashion. The spleen showed a significant increase in V from 5 to 12 days after the administration. Groups of mice were injected intraperitoneally with doses ranging from 0.1 to 8 mg V/kg and tissues were collected after 1 and 5 days. At one day after injection, most tissues showed higher amounts of V at dose levels of 5 mg/kg than would be expected from a linear dose-dependent relationship. At 5 days, all tissues showed a linear dose-concentration relationship. The tissue: blood ratios indicated that at one day after injection there was an increased accumulation of V in tissues with increased dose. At five days after injection, the tissue:blood ratios were greater than unity for all tissues except brain. The increased accumulation of V in tissues with increased dose observed at one day was not observed at five days.

Notizen: Abstract Aerial application of the insecticide Nuvacron 40® (monocrotophos) had no significant effect on the cholinesterase level of plasma and erythrocytes of cattle, chicken, buffaloes, and human volunteers exposed to the spray. Contamination of canal water with the pesticide was completely eliminated within 24 hr, whereas that in the soil was reduced by 80% in 72 hr. The degradation of insecticide residue in grass was about 90% in seven days and in cotton leaves about 85% for the same period.

Notizen: Abstract Acute toxicity tests of selenium dioxide were conducted for 96 to 336 hr in intermittent-flow bioassay systems using six species of freshwater fish. The decreasing order of species sensitivity was: fathead minnow, flagfish, brook trout, channel catfish, goldfish, and bluegill. Curves relating median lethal concentration to exposure time for each species exposed for more than 168 hr were sigmoid in shape and were characterized by a change in slope indicating a more rapid mortality rate after 96 to 168 hr toxicant exposure. The 96-hr LC50 estimates ranged from 2.9 mg/L SeO2 for fathead minnow fry to 40.0 mg/L for bluegill juveniles. Effects of brief toxicant exposure (24 hr) on fathead minnow and flagfish juveniles included limited delayed mortality and no effects on growth over a 28-day period.

Notizen: Abstract Methods for extraction, cleanup, and analysis of samples of water, mud, and fish containing trace quantities of Abate have been developed. Water was extracted by high-speed stirring of 10 ml of hexane in a 300-ml sample. The extracts were evaporated and analyzed by gas chromatography with a limit of detection of 0.00003 ppm. Dried mud samples were extracted by shaking with acetone. An aliquot of the acetone extract was diluted with water and the Abate extracted into 10 ml of hexane by high-speed stirring. The extracts were analyzed by gas chromatography. Fish were extracted with methylene chloride, cleaned up on a silica gel column, and analyzed by gas chromatography. The limit of sensitivity of the methods for mud and fish was found to be 0.001 ppm. Fish samples were stored for 3 weeks in 10% formalin containing 5% sodium thiosulfate without significant loss of Abate residues. A biological magnification of greater than 100 was observed in fish exposed to Abate for 16 hr at concentrations of 0.02 and 0.002 ppm.

Notizen: Abstract Toxic, neurochemical and behavioral alterations were evaluated in ducks fed various dietary levels of dieldrin. Increasing amounts of dieldrin in the diet caused an appreciable decrease in the levels of three biogenic amines in whole brain,i.e. serotonin, norepinephrine and dopamine. No effect was noted in whole brain gamma aminobutyric acid contents. Hepatic microsomal enzymes were assayed in these birds usingp-nitroanisol andO-ethyl-O-p-nitrophenyl benzenethionophosphate as substrates. Sublethal amounts of dieldrin caused an increase in hepatic drug metabolizing enzymes. Similar alterations were noted in liver protein, deoxyribonucleic acid and ribonucleic acid contents. Studies involving encounters between mallard drakes indicated a decline in the tendency for dieldrin exposed drakes to take the initiative and establish rights of access in approach confrontations. Although many of these changes are compatible with life processes, their significance is not well understood, especially in terms of lifelong exposure to persistent pesticides. The possible relationship between neurochemical alterations and the mechanisms of insecticide neurotoxicity is discussed.

Notizen: Abstract Selenium (Se) is an essential as well as a toxic trace element in animal and human nutrition. The immune system is a known target of Se intoxication. The objectives of the present study were to determine the effects of oral exposure to inorganic and organic forms of Se on the murine immune system and to compare the relative toxicity of the different chemical forms. Male BALB/c mice, 6–7 weeks of age, were exposed continuously to 0, 1, 3 or 9 ppm of Se as sodium selenite or seleno-L-methionine in the drinking water for 14 days. Following the treatment period mice were euthanized; trunk blood, spleen, thymus, liver and kidney were aseptically collected and organs weighed. Single-cell splenocyte cultures were made from the spleens and used to determine the effects of Se treatment on mitogen-induced lymphocyte blastogenesis and cytokine production. There were no changes in the 0 and 1 ppm Se groups as selenite. The thymus/body weight ratio was significantly reduced at 3 ppm Se as sodium selenite, and all other parameters remained unaffected. Exposure to 9 ppm of Se as sodium selenite resulted in marked decrease in body weight gain and relative organ weights. Treatment of mice with 9 ppm Se as sodium selenite increased erythrocyte counts in peripheral blood, reduced splenic cellularity, but increased the basal rate of splenocyte proliferation and induced a dose-dependent increase in phytohemagglutinin-P-induced lymphocyte proliferation. Sodium selenite at this dose increased the production of proinflammatory cytokines, tumor necrosis factor α and interleukin-1β, in lipopolysaccharide-stimulated splenic macrophages. Mice exposed to Se as seleno-L-methionine in the drinking water did not display any effects on the parameters examined at the dose range in this study. Results indicated that splenic macrophages and lymphocytes are sensitive to Se intoxication and there is a disparity in the immune system toxicity of inorganic and organic forms of Se administered via the drinking water, inorganic Se being more toxic.