Lead accumulation and elimination in tissues of Prussian carp, Carassius gibelio (Bloch, 1782), after long-term dietary exposure, and depuration periods

We studied the bioaccumulation of lead in selected tissues of Prussian carp Carassius gibelio (Bloch, 1782) during 12 and 24 months exposure to different doses of this metal in feed and the elimination of lead from tissues during the following 12-month depuration period. Lead concentration was determined using atomic absorption spectrometry method. The highest lead concentrations were observed at 2.0 +/- 0.54 to 7.4 +/- 1.1 mg kg(-1) in the kidney, 3.0 +/- 0.13 to 5.2 +/- 0.17 mg kg(-1) in the bone, and 4.5 (+/- 0.4) mg kg(-1) in the hepatopancreas of fish from groups exposed to lead dietary concentration from 8 to 49 mg kg(-1) for 24 months. The rate of accumulation were generally the highest at the beginning of exposure as evidenced by the highest monthly increments of bioaccumulation observed after 3 months of contamination for muscles, hepatopancreatic gland, intestine, and gills. Also analysis of the monthly increments of lead bioaccumulation in bone tissue and the highly significant coefficients of correlation indicate that the dynamics of accumulation are clearly dependent on dose of exposure. Depuration of accumulated lead from the organs depended mainly on tissue and duration of elimination period. Very rapid depuration was observed in soft tissues such as the intestine or muscles. Very low elimination was observed for scales and bones where until the end of the experiment highly significant lead concentration differences were observed in all groups in relation to the control group. Chronic dietary exposure in the range of 8-49 mg Pb kg(-1) resulted in no significant effects on the growth and survival of Prussian carp females.