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1.
Badreddine Sellami Hela Louati Mohamed Dellali Patricia Aissa Ezzeddine Mahmoudi Ana Varela Coelho David Sheehan 《Environmental science and pollution research international》2014,21(6):4461-4472
The effects of permethrin (PER) on a panel of antoxidant enzymes; superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST) and indices of protein oxidation status (carbonylation and free thiols) were determined in digestive gland and gills of the clam Ruditapes decussatus. Animals were exposed to 100 ppb PER for 2 days. These enzyme activities increased significantly in digestive gland (p?<?0.05) after PER treatment and oxidative modification of proteins was detected in both gill and digestive gland extracts using redox proteomics. PER exposure significantly reduced the amount of protein free thiol groups in digestive gland rather than in gill, when compared to controls. Conversely, digestive gland showed significantly higher levels of carbonylated proteins than gill after PER exposure. Some proteins were successfully identified by mass spectrometry of tryptic peptides. Our data suggest that digestive gland of R. decussatus can be used as a model tissue for investigating environmental risk of PER contamination. 相似文献
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Kenneth R. Sheehan Michael P. Strager Stuart A. Welsh 《Environmental Modeling and Assessment》2013,18(2):209-219
Stream habitat assessments are commonplace in fish management, and often involve nonspatial analysis methods for quantifying or predicting habitat, such as ordinary least squares regression (OLS). Spatial relationships, however, often exist among stream habitat variables. For example, water depth, water velocity, and benthic substrate sizes within streams are often spatially correlated and may exhibit spatial nonstationarity or inconsistency in geographic space. Thus, analysis methods should address spatial relationships within habitat datasets. In this study, OLS and a recently developed method, geographically weighted regression (GWR), were used to model benthic substrate from water depth and water velocity data at two stream sites within the Greater Yellowstone Ecosystem. For data collection, each site was represented by a grid of 0.1 m2 cells, where actual values of water depth, water velocity, and benthic substrate class were measured for each cell. Accuracies of regressed substrate class data by OLS and GWR methods were calculated by comparing maps, parameter estimates, and determination coefficient r 2. For analysis of data from both sites, Akaike’s Information Criterion corrected for sample size indicated the best approximating model for the data resulted from GWR and not from OLS. Adjusted r 2 values also supported GWR as a better approach than OLS for prediction of substrate. This study supports GWR (a spatial analysis approach) over nonspatial OLS methods for prediction of habitat for stream habitat assessments. 相似文献
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The analysis presented in this paper shows that water solubility as well as the n-octanol/water partition coefficient are useful indicators of the tendency of organic chemicals to bioaccumulate. It is suggested that these physico-chemical data be used as screening test for organic chemical bioaccumulation in aquatic organisms, such as the mussel . 相似文献
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Sheehan P Dewhurst RE James S Callaghan A Connon R Crane M 《Environmental geochemistry and health》2003,25(1):9-16
Part IIA of the Environmental Protection Act 1990 requires environmental regulators to assess the risk of contaminants leaching from soils into groundwater (DETR, 1999). This newly introduced legislation assumes a link between soil and groundwater chemistry, in which rainwater leaches contaminants from soil into the saturated zone. As the toxicity of both groundwater and overlying soils is dependent upon the chemicals present, their partitioning and their bioavailability, similar patterns of soil, leachates and groundwater toxicity should be observed at contaminated sites. Soil and groundwater samples were collected from different contaminated land sites in an urban area, and used to determine relationships between soil chemistry and toxicity, mobility of contaminants, and groundwater chemistry and toxicity. Soils were leached using water to mimic rainfall, and both the soils and leachates tested using bioassays. Soil bioassays were carried out using Eisenia fetida, whilst groundwater and leachates were tested using the Microtox test system and Daphnia magna 48 h acute tests. Analysis of the bioassay responses demonstrated that a number of the samples were toxic to test organisms, however, there were no significant statistical relationships between soil, groundwater and leachate toxicity. Nor were there significant correlations between soil, leachates and groundwater chemistry. 相似文献
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Sellami Badreddine Mouhamed Dellali Ezzeddine Mahmoudi David Sheehan Beyrem Hamouda 《Chemistry and Ecology》2017,33(4):309-324
Mediterranean mussels Mytilus galloprovincialis is among the most widely used bioindicators, and anthracene (AN) is one of the most commonly found hydrocarbons in the aquatic environment. M. galloprovincialis were exposed to nominal concentrations of 0.05, 0.15 and 0.4?μg/L AN. Chemical analysis using high-performance liquid chromatography revealed the uptake of AN in the whole soft body and digestive gland at different amounts. After a short exposure (2, 4 and 8 days), the results revealed that AN induced malondialdehyde (MDA), glutathione (GSH) and acetylcholinesterase (AChE) activity in digestive gland. Our findings demonstrated also that AN reduced the filtration rates in a concentration-dependent manner. Increase in lipid peroxidation (MDA content) in digestive gland (p?.05) can possibly indicate that AN can cross the membrane barrier, leading to cellular membrane alteration. Decrease in GSH content following the concentration and exposure time support MDA content result. AN exposure significantly reduced AChE activity as a more sensitive biomarker in digestive gland in a time- and concentration-dependent manner. This review provides a framework for the understanding of toxicological effects of AN under an environmental point of view. It provides also original data on the distribution of AN in M. galloprovincialis, where digestive gland constitutes a valuable organ for investigating AN biotransformation and toxicity. 相似文献
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Kahl JS Nelson SJ Fernandez I Haines T Norton S Wiersma GB Jacobson G Amirbahman A Johnson K Schauffler M Rustad L Tonnessen K Lent R Bank M Elvir J Eckhoff J Caron H Ruck P Parker J Campbell J Manski D Breen R Sheehan K Grygo A 《Environmental monitoring and assessment》2007,126(1-3):9-25
This paper is an overview of this special issue devoted to watershed research in Acadia National Park (Acadia NP). The papers
address components of an integrated research program on two upland watersheds at Acadia NP, USA (44° 20′ N latitude; 68° 15′
E longitude). These watersheds were instrumented in 1998 to provide a long-term foundation for regional ecological and watershed
research. The research was initiated as part of EPA/NPS PRIMENet (Park Research and Intensive Monitoring of Ecosystems Network),
a system of UV-monitoring stations and long-term watershed research sites located in US national parks. The initial goals
at Acadia NP were to address research questions about mercury, acid rain, and nitrogen saturation developed from prior research.
The project design was based on natural differences in forests and soils induced by an intense wildfire in one watershed in
1947. There is no evidence of fire in the reference watershed for several hundred years. We are testing hypotheses about controls
on surface water chemistry, and bioavailability of contaminants in the contrasting watersheds. The unburned 47-ha Hadlock
Brook watershed is 70% spruce-fir mature conifer forest. In contrast, burned 32-ha Cadillac Brook watershed, 4 km northeast
of the Hadlock watershed, is 20% regenerating mixed northern hardwoods and 60% shrub/rocky balds. Differences in atmospheric
deposition are controlled primarily by forest stand composition and age. The watersheds are gauged and have water chemistry
stations at 122 m (Cadillac) and 137 m (Hadlock); watershed maximum elevations are 468 and 380 m, respectively. The stream
water chemistry patterns reflect, in part, the legacy of the intense fire, which, in turn, controls differences in forest
vegetation and soil characteristics. These factors result in higher nitrogen and mercury flux from the unburned watershed,
reflecting differences in atmospheric deposition, contrasting ecosystem pools of nitrogen and mercury, and inferred differences
in internal cycling and bioavailabilty. 相似文献
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Michael Sheehan 《Journal of the American Water Resources Association》1981,17(2):275-279
ABSTRACT: This article discusses the implications of accepting various standards of scientific evidence in disputes arising over the dumping of potentially hazardous materials into public waterways and drinking water supplies. Standards based on the types of risks and levels of benefits suffered and received by adjacent populations are evaluated within the context of the several pieces of federal legislation which relate to water quality. A case study of Reserve Mining Corporation's dumping of taconite wastes into Lake Superior is presented to illustrate the ramifications of decisions based on differing perspectives of the problem and its impacts by the courts, the affected public, RMC, and the regulatory agencies involved. 相似文献