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Background and Objective: Fish is one of the creatures which have the bio-accumulation of heavy metals. Terapon puta belongs to the order of Perciformes, is a benthic species in the waters of the Persian Gulf. This study was performed to evaluate the bio-accumulation of iron and nickel metals in the muscle of Terapon puta.
Methods: This descriptive-analytical study was performed on 30 pieces of Terapon puta caught in the Jefreh pier area of Bushehr, north of the Persian Gulf during the summer of 2019. Length (mm) and total weight (g) of fish were measured. The concentrations of iron and nickel in fish muscle tissue for human consumption were compared with international standards and calculated according to the US Environmental Protection Agency (USEPA) method for fish consumption, estimated daily uptake (EDI), and pollutant risk index (CR). After preparation, bioassay and, digestion of fish muscle with concentrated nitric acid, the concentration of iron and nickel (mg/kg) in muscle tissue was measured with ICP-OES.
Results: The mean concentrations of iron and nickel in muscle tissue of fish samples were calculated 36.08±15.72 and 0.39±0.13 mg/kg, respectively. There was a significant difference between the concentrations of iron and nickel in the muscle tissue of the Terapon puta in the sampling area (P<0.05) and these values were lower than the standard and meaningless the muscle tissue of the Terapon puta in the sampling area compared to the FDA standard. The highest concentration of metals was observed in the length class of 20-25 cm and weight class of 230-260 g. Linear regression analysis showed that a strong increase (R²=0.9) between the concentration of iron and nickel with the length and total weight of fish. The daily uptake of both metals was obtained by consuming Terapon puta muscle tissue for consumers below the USEPA reference dose. The concentration of iron in the muscle tissue of Terapon puta was lower than the international standards. Nickel concentration was more than allowable limit according to WHO standards. The carcinogenicity risk index for nickel was acceptable.
Conclusion: Concentrations of iron and nickel in Terapon puta were considered acceptable for human consumption in terms of toxicity. The risk index for Terapon puta was less than one; therefore, the consumption of Terapon puta will not cause adverse health effects for consumers.