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ABSTRACT: This study proposes short-term sublethal assays for the tropics using the fish Poecilia reticulata. Assays were evaluated under realistic exposure scenarios by simulating a runoff over an agricultural area sprayed with deltamethrin (Decis). In situ assays were performed inside microcosms set up to simulate runoff water entrance in lentic systems. Laboratory assays were conducted with water samples from the microcosms. In both assays the biochemical parameters were similarly responsive to Decis, with a significant inhibition of acetylcholinesterase (30-46%) and induction of lactate dehydrogenase (33-67%) and glutathione S-transferases (48-176%) activities, observed as of the lowest Decis dose. Postexposure feeding was more sensitive in the laboratory assay than in situ. Among the additional potential stressors, only acetylcholinesterase was significantly influenced by the runoff per se. The proposed methodologies were well adapted for assays with P. reticulata, as organisms were easily deployed and retrieved and enzymatic activities and postexposure feeding were sensitive endpoints.
Ecotoxicology and Environmental Safety 07/2010; 73(5):893-9. · 2.29 Impact Factor
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ABSTRACT: With the aim of using Mytilus galloprovincialis acetylcholinesterase (AChE) and glutathione S-transferases (GST) activities as biomarkers of environmental contamination in risk assessment studies along the northwest Portuguese coast, the objective of this study was to provide background information related to: (1) baseline values of these enzymatic activities both in reference and contaminated areas and their responsiveness as indicators of exposure to environmental contaminants; (2) the importance of seasonal variations of such biomarkers in M. galloprovincialis along this area. For this, the activity of these enzymes was seasonally determined in mussels collected from four sites, including a reference and three stations with different contamination sources along the referred area. Statistically significant differences on both enzymatic activities were found among the four sampling stations, at the four sampling periods. In comparison to the reference station, lower AChE and higher GST activity values were found in mussels collected in stations potentially contaminated by pesticides and domestic/industrial effluents and in mussels collected in the vicinity of an oil refinery and an industrial/mercantile harbour, respectively. The results obtained in this work highlighted the potential suitability of these biomarkers to be used as components of environmental monitoring programs in risk assessment studies along the northwest Portuguese coast. Since a seasonal variation in both enzymatic activities was found, the possible implications of such variability in the use of these enzymes as environmental biomarkers are also discussed.
Environmental Monitoring and Assessment 07/2005; 105(1-3):309-25. · 1.40 Impact Factor
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Bulletin of Environmental Contamination and Toxicology 11/2001; 67(4):470-5. · 1.02 Impact Factor
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[show abstract]
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ABSTRACT: This study proposes short-term sublethal assays for the tropics using the fish Poecilia reticulata. Assays were evaluated under realistic exposure scenarios by simulating a runoff over an agricultural area sprayed with deltamethrin (Decis). In situ assays were performed inside microcosms set up to simulate runoff water entrance in lentic systems. Laboratory assays were conducted with water samples from the microcosms. In both assays the biochemical parameters were similarly responsive to Decis, with a significant inhibition of acetylcholinesterase (30–46%) and induction of lactate dehydrogenase (33–67%) and glutathione S-transferases (48–176%) activities, observed as of the lowest Decis dose. Postexposure feeding was more sensitive in the laboratory assay than in situ. Among the additional potential stressors, only acetylcholinesterase was significantly influenced by the runoff per se. The proposed methodologies were well adapted for assays with P. reticulata, as organisms were easily deployed and retrieved and enzymatic activities and postexposure feeding were sensitive endpoints.
Ecotoxicology and Environmental Safety.
