Heavy Metal Accumulation in Soybeans Cultivated in Iran, 2015-2016

Background: Due to environmental contamination in recent years, contamination of food chain by heavy metals is not far-fetched. The purpose of this study is to determine heavy metals in soybeans cultivated in Iran to monitor the food chemical contaminants. Methods: To assess metal contamination, four varieties (Sahar, Katool, Williams, and M7) of soybean cultivated in Iran, were collected. Metal concentration of samples was analyzed by inductively coupled plasma-optical emission spectrophotometer (ICP-OES). Results: The concentrations of Arsenic (As), Cadmium (Cd), Copper (Cu), Nickel (Ni), Lead (Pb), and Zinc (Zn) in soybean samples were ranged from 0.008 to 0.21, 0.008 to 0.16, 9.51 to 87.71, 4.08 to 22.37, 0.015 to 1.18, and 35.53 to 65.02 mg/kg, respectively. Taken together, findings of this study showed that heavy metal content of all taken samples, except Pb in M7 variety, were below the maximum limits. So, there is no need to concern about the presence of heavy metal contents in soybeans cultivated in Iran. Conclusion: Since soybeans are used in production of other soy-based products (such as soy milk, soy cheese, soy sauce), regular monitoring of soybean in terms of heavy metals is necessary.