Bioaccumulation and elimination rate of cobalt in Capoeta fusca under controlled conditions

The objective of the present study was to investigate the pattern of accumulation and elimination of cobalt in selected organs of Capoeta fusca, after chronic exposure. Samples of C. fusca were obtained from a qanat in Birjand between July and September 2010. Cobalt accumulation was studied in fish exposed to 6.8 mg L-1 of cobalt for 15 days and the elimination was investigated in the contaminated fish samples placed in tap water for another 15 days. Using atomic absorption spectrophotometry it was found that the accumulation of cobalt in tissues was in the following order: liver>muscle>gill>skin. The elimination of cobalt was in the following order: skin>gill>muscle>liver. The bioaccumulation and elimination of cobalt were significant in the organs of C. fusca (P<0.01). The accumulation of cobalt in C. fusca was rapid and increased with an increase in metal concentration in water and the duration of exposure. The results of the present study showed that the accumulation and elimination of cobalt in C. fusca depend on the type of organs and the duration of exposure.