Study of accumulation of copper by carp (Cyprinus carpio L.) ‐ adaptation analysis of bioconcentration by the gills

Abstract

Experimenta were carried out with a cyprinid, Cyprinus carpio, adopting a semi‐static type of test during 3 weeks and using 2/10 of previously determined 48 h copper LC 50 at three different water hardness (50, 100, 300 mg.l^‐1 as CaCO₃). Bioaccumulation was studied using a sample of gills from three fish that were kept overnight in toxic free water for elimination of the metal adsorbed on surface being samples taken at the start of experimenta and every week. Adaptation assays were also performed submitting fish to increasing proportions of LC50. Bioconcentration factor (BCF) and pollution factor (PF) were determined and a relationship between copper concentrations in water and in the gills was found. Although considering only an external transtegumentary route, it can be admitted that copper concentration in gills might be used as a first approach for a bioindicator of chronic contamination. Thus, if the concentration of copper in water is known, the concentration in aquatic organisms can be calculated from their BCF.