Biochemical stress responses in tissues of the cichlid fish Cichlasoma dimerus exposed to a commercial formulation of endosulfan.

Median lethal concentration (LC(50)) and sublethal effects of the commercial endosulfan formulation Zebra Ciagro(®) on the fish Cichlasoma dimerus were studied. The 96-h LC(50) was estimated as 17.7 μg/L.

Multiple biomarkers responses in Prochilodus lineatus allowed assessing changes in the water quality of Salado River basin (Santa Fe, Argentina).

This field study assessed water quality of Salado River basin by using a set of biomarkers in the fish Prochilodus lineatus. Multiple biomarkers were measured, including morphological indexes (condition factor, liver somatic index), hematological (red and white blood cells) and biochemical (glucose, total protein and cholinesterase activity) parameters. Besides, detoxication and oxidative stress markers (antioxidant enzymes, lipid peroxidation) were measured in liver, gills and kidney.

Accumulation and elimination of chromium by freshwater species exposed to spiked sediments.

The bioaccumulation and elimination capacity of chromium were examined in four freshwater species: the submersed aquatic plant Ceratophyllum demersum (Ceratophyllaceae), the oligochaete Limnodrilus udekemianus (Tubificidae), the crab Zilchiopsis collastinensis (Decapoda), and the fish Cnesterodon decemmaculatus (Poeciliidae). All of the species were exposed simultaneously to sediments spiked with Cr (K(2)Cr(2)O(7)) at different concentrations for 28 days, followed by 7 days without Cr to evaluate the concentration of residual Cr. We found that Cr accumulated in the tissues of all four species.