Mercury (Hg) is a widespread environmental contaminant and its organic form, methylmercury (MeHg), has been known as a potent neurotoxic since the Minamata tragedy. In the Amazonian basin, gold mining leads to MeHg biomagnification all along the food web, culminating in piscivorous fish, ultimately responsible for contamination of human beings through fish consumption. In order to assess the biological impact of dietary MeHg on fish at the genome scale, we contaminated zebrafish with MeHg-contaminated food for 25 days (13.
View Article and Find Full Text PDFA study was undertaken to examine cadmium accumulation in freshwater biofilm, its effects on biofilm development and on diatom community structure in laboratory experimental conditions. A suspension of a biofilm originated from the Riou-Mort River (South West France) was inoculated into three experimental units containing clean glass substrates under laboratory conditions. Settling and already developed biofilms were exposed to a Cd concentration of 100 microg L(-1).
View Article and Find Full Text PDFThe relationships between diatom species and cadmium (Cd) accumulated in biofilms of the Riou-Mort River (SW, France) were studied in July 2004 and March 2005. Biofilms were sampled from artificial substrates immersed along a metallic pollution gradient during 20 days. Dynamics of diatom communities and cadmium accumulation were followed by collecting samples after 4, 7, 14 and 20 days of biofilm colonization.
View Article and Find Full Text PDFMercury and more specifically methylmercury have been reported as hazardous environmental pollutants able to accumulate along the aquatic food chain with severe risk for animal and human health. Adult male zebrafish (Danio rerio) were distributed in two groups: a control group (fed with uncontaminated food) and a MeHg-contaminated group (fed with food containing 13.5μgHgg(-1) (dry wt)).
View Article and Find Full Text PDFGoal, Scope And Background: The Gironde estuary is considered as a reference ecosystem with a large fish assemblage (75 species) and the presence of eleven diadromous species. However, geochemical studies and biomonitoring using oysters have shown high metal pollution levels. During the December 1999 hurricane, more than 5,000 young Siberian sturgeons (Acipenser baerii) accidentally escaped from a fish farm into the estuary, where this species had not been present until then.
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