Heavy metals bioaccumulation in fish of southern Iran and risk assessment of fish consumption

Background: This study purposed to assess the health risks of heavy metals including nickel (Ni), chromium (Cr), mercury (Hg), and lead (Pb) in three widely-consumed fish from the coast of Bandar Abbas (Persian Gulf) and to determine the maximum amounts allowed for consumption according to the degree of contamination. Methods: This cross-sectional study was conducted in the summer and fall of 2013. Thunnus tonggol and Liza klunzingeri were selected from the Bandar Abbas market, and Pleuronectiformes were caught from the sea. Heavy metal concentrations were determined by atomic absorption. Risk assessment and allowable consumption levels were determined according to methods provided by the US Environmental Protection Agency (USEPA). Results: The highest average levels of Ni and Cr in Thunnus tonggol were 0.059 and 0.234 (μg/g dry weight), respectively. The highest average level of Hg in Pleuronectiformes was 0.095 (μg/g dry weight), and the highest average level of Pb in Liza klunzingeri was 0.006 (μg/g dry weight). The target hazard quotient (THQ) for all analyses of metals in the studied species and the hazard index (HI) were less than 1 for all three species. Conclusion: The results showed that despite Ni, Cr, Hg, and Pb pollution, the consumption of up to 4 (kg/d) of Thunnus tonggol by adults and up to 2.2 (kg/d) by children does not cause health problems in terms of the tested heavy metals. For Liza klunzingeri, these levels are 7.32 and 4.02 (kg/d), respectively.