ALBERT

Description: Pigmy Basin sediments cored in Hole 619 of Deep Sea Drilling Project Leg 96 are silty clays composed, on the average, of 〈 1% sand, 37% silt, 48% clay, and 14% carbonate minerals. Except for minor grain dissolution in some silt grains, there is no distinctive variation with depth in either composition or texture of the sand- and silt-sized minerals. This suggests a constant source of sediment supply and little diagenetic alteration of these size fractions. Clay minerals are dominated by smectite or, more precisely, montmorillonite. On the average, the clay-sized fraction consists of 48% smectite and mixed layer minerals, 30% illite, and 23% total kaolinite and chlorite. There appears to be a slight decrease in smectite and concomitant increases in other clay minerals with depth. These changes are further substantiated by the variations of ammonium acetate exchangeable K+, Mg2+, and Na+ in bulk samples. Thus, incipient diagenesis of Pigmy Basin sediments is evidenced in the mineralogical and associated chemical characteristics of the clay fractions.

Description: The interstitial water received at UCLA from Leg 7 (Guam to Hawaii) consisted of forty-two samples of approximately 5 milliliters each, three samples of approximately 10 milliliters each, and three samples of approximately 100 milliliters each. These pore waters had been squeezed from sediments consisting primarily of biogenic ooze, and had been collected at five different drilling sites along the route. High cobalt value were observed at Site 66 and were accompanied by a relatively high manganese concentration, but more normal iron, nickel and copper concentrations. This apparent cobalt enrichment could not be explained at the time of procedure. The line Islands area were Site 66 is situated was later notoriously known for its high Co values in manganese crust deposits (see, He, G., Ma, W., Song, C., Yang, S., Zhu, B., Yao, H., Jiang, X., Cheng, Y., 2011. Distribution characteristics of seamount cobalt-rich ferromanganese crusts and the determination of the size of areas for exploration and exploitation. Acta Oceanologica Sinica 30, 63–75. doi:10.1007/s13131-011-0120-9).

Description: The toxicity of sediments in Biscayne Bay and many adjoining tributaries was determined as part of a bioeffects assessments program managed by NOAA’s National Status and Trends Program. The objectives of the survey were to determine: (1) the incidence and degree of toxicity of sediments throughout the study area; (2) the spatial patterns (or gradients) in chemical contamination and toxicity, if any, throughout the study area; (3) thespatial extent of chemical contamination and toxicity; and (4) the statistical relationships between measures of toxicity and concentrations of chemicals in the sediments.The survey was designed to characterize sediment quality throughout the greater Biscayne Bay area. Surficial sediment samples were collected during 1995 and 1996 from 226 randomly-chosen locations throughout nine major regions. Laboratory toxicity tests were performed as indicators of potential ecotoxicological effects in sediments. A battery of tests was performed to generate information from different phases (components) of the sediments. Tests were selected to represent a range in toxicological endpoints from acute to chronic sublethal responses. Toxicological tests were conducted to measure: reduced survival of adult amphipods exposed to solid-phase sediments; impaired fertilization success and abnormal morphological development in gametes and embryos, respectively, of sea urchins exposed to pore waters; reduced metabolic activity of a marine bioluminescentbacteria exposed to organic solvent extracts; induction of a cytochrome P-450 reporter gene system in exposures to solvent extracts; and reduced reproductive success in marine copepods exposed to solid-phase sediments.Contamination and toxicity were most severe in several peripheral canals and tributaries, including the lower Miami River, adjoining the main axis of the bay. In the open basins of the bay, chemical concentrations and toxicity generally were higher in areas north of theRickenbacker Causeway than south of it. Sediments from the main basins of the bay generally were less toxic than those from the adjoining tributaries and canals. The differenttoxicity tests, however, indicated differences in severity, incidence, spatial patterns, and spatial extent in toxicity. The most sensitive test among those performed on all samples, a bioassay of normal morphological development of sea urchin embryos, indicated toxicity was pervasive throughout the entire study area. The least sensitive test, an acute bioassay performed with a benthic amphipod, indicated toxicity was restricted to a very small percentageof the area.Both the degree and spatial extent of chemical contamination and toxicity in this study area were similar to or less severe than those observed in many other areas in the U.S. The spatial extent of toxicity in all four tests performed throughout the bay were comparable tothe “national averages” calculated by NOAA from previous surveys conducted in a similar manner.Several trace metals occurred in concentrations in excess of those expected in reference sediments. Mixtures of substances, including pesticides, petroleum constituents, trace metals, and ammonia, were associated statistically with the measures of toxicity. Substances most elevated in concentration relative to numerical guidelines and associated with toxicity included polychlorinated biphenyls, DDT pesticides, polynuclear aromatic hydrocarbons, hexachloro cyclohexanes, lead, and mercury. These (and other) substances occurred in concentrations greater than effects-based guidelines in the samples that were most toxic in one or more of the tests. (PDF contains 180 pages)

Description: Center for Coastal Monitoring and Assessment

Description: The toxicity of sediments in Sabine Lake, Texas, and adjoining Intracoastal Waterway canals was determined as part of bioeffects assessment studies managed by NOAA’s National Status and Trends Program. The objectives of the survey were to determine: (1) the incidence and degree of toxicity of sediments throughout the study area; (2) the spatial patterns (or gradients) in chemical contamination and toxicity, if any, throughout the study area; (3) the spatial extent of chemical contamination and toxicity; and (4) the statistical relationships between measures of toxicity and concentrations of chemicals in the sediments.Surficial sediment samples were collected during August, 1995 from 66 randomly-chosen locations. Laboratory toxicity tests were performed as indicators of potential ecotoxicological effects in sediments. A battery of tests was performed to generate information from different phases (components) of the sediments. Tests were selected to represent a range in toxicological endpoints from acute to chronic sublethal responses. Toxicological tests were conducted to measure: reduced survival of adult amphipods exposed to solid-phase sediments; impaired fertilization success and abnormal morphological development in gametes and embryos, respectively, of sea urchins exposed to pore waters; reduced metabolic activity of a marine bioluminescent bacteria exposed to organic solvent extracts; and induction of a cytochrome P-450 reporter gene system in exposures to solvent extracts of the sediments.Chemical analyses were performed on portions of each sample to quantify the concentrations of trace metals, polynuclear aromatic hydrocarbons, and chlorinated organic compounds. Correlation analyses were conducted to determine the relationships between measures of toxicity and concentrations of potentially toxic substances in the samples.Based upon the compilation of results from chemical analyses and toxicity tests, the quality of sediments in Sabine Lake and vicinity did not appear to be severely degraded. Chemical concentrations rarely exceeded effects-based numerical guidelines, suggesting that toxicant-induced effects would not be expected in most areas. None of the samples was highly toxic in acute amphipod survival tests and a minority (23%) of samples were highly toxic in sublethal urchin fertilization tests. Although toxic responses occurred frequently (94% of samples) in urchin embryo development tests performed with 100% pore waters, toxicity diminished markedly in tests done with diluted pore waters. Microbial bioluminescent activity was not reduced to a great degree (no EC50 〈0.06 mg/ml) and cytochrome P-450 activity was not highly induced (6 samples exceeded 37.1 ug/g benzo[a]pyrene equivalents) in tests done with organic solvent extracts. Urchin embryological development was highly correlated with concentrations of ammonia and many trace metals. Cytochrome P450 induction was highly correlated with concentrations of a number of classes of organic compounds (including the polynuclear aromatic hydrocarbons and chlorinated compounds). (PDF contains 51 pages)

Description: Center for Coastal Monitoring and Assessment