عبدالعلی موحدی نیا

Two hundred and forty fishes including Hypophthalmichthys molitrix, Silurus glanis, and Esox lucius (male and female) were collected from four sampling sites in Anzali wetland including Anzali, Khazarvila, Pirbazar, and Beshman through late April 2011. The potential health risk of Pb, Sn, and Zn to consumers was assessed by calculating the estimated daily intake, estimated weekly intake, hazard quotient, maximum allowable fish consumption rate, and monthly allowable consumption rate. In addition, the tissue structure of liver was studied in fish. Concentrations of Pb, Sn, Zn, Hg, Cu, and Ni were also measured in water and sediment. Based on the results, the accumulation and distribution patterns of metals in fish from different stations were as follows: Zn>Sn>Pb, H. molitrixCu>Hg>Sn>Ni>Pb. Liver samples had a normal histological structure consisted of intersinusoidal hepatocyte cords and hepatic triad in all fish species collected from Pirbazar, Beshman, and Khazarvila stations. In contrast, tissue changes including melanomacrophage aggregations and hemorrhage were detected in S. glanis and E. lucius collected from Anzali station. In sum, the levels of permissible tolerable daily intake and permissible tolerable weekly intake for metals (Pb, Sn, and Zn) in all fish species were lower than the allowable limit defined by Joint FAO/WHO Committee; therefore, consumption of these fishes seems to be safe.