Metals Analysis in common carp (Cyprinus carpio) from Shirinsu Wetland, Hamedan province, Iran

Background & Aims of the Study: Concentrations of Cd, Hg and As were measured by atomic absorption spectrometry (AAS) in muscle, liver and gill tissues of common carp from the Shirinsu Wetland during February to March 2013. Methods: Fish samples (Cyprinus carpio) were caught from Shirinsu Wetland, western Iran from February to March 2013. Specimens were frozen in prewashed polyethylene bags and frozen samples brought to the laboratory in ice chests. Samples (2 g) were digested with 5 ml of HNO 3 (65% v/v), 1 ml of H 2 O 2 (30% v/v) with a microwave oven. A blank digest was carried out in the same way. The digestion program began at a potency of 1200W then ramped for 10 min, after which samples were held for 10 min at 1200W. The second step began at a potency of 0W and held for 15 min. All metal concentrations were determined on a wet weight basis as μg g −1 . Results: Metal levels measured in muscle tissue were in the following ranges (μg g −1 ): Cd 0.007-0.011, Hg 0.006-0.01 and As not detected. In liver tissue were (μg g −1 ): Cd 0.035-0.043, Hg and As not detected. In gill tissue were (μg g −1 ): Cd 0.31-0.55, Hg 0.002-0.004 and As 0.001-0.003. The results presented on metal contents in the examined tissues give an indication of the environmental conditions. Concentrations of Cd, Hg and As obtained were far below the established values by the European Community Regulations. However, Cd level found in gill tissue was higher than the recommended legal limits for human consumption and as such may cause a human health issue. Conclusion: Analytical data shows that the metal concentrations for the fish tissues were generally within the FAO/WHO, ASTDR and EEC recommended limits for fish. Therefore there is no serious health risk associated with the consumption of the three studied metals in the muscle and liver tissues analyzed.