A Comparative Study on Mineral Contents of Soybean by Two Methods of Digestion Using ICP-OES Technique: A Risk Assessment Study

Introduction: In recent years, the contamination of food with heavy metals has received much attention. Plants can absorb metal pollutants through contaminated water, soil, and air. Materials and Methods: In the current study, accumulation of minerals in three types of soybeans was investigated by wet and dry digestion methods using ICP-OES technique. Thereafter, the metals' health risk was assessed by estimated daily intake, toxic hazard quotient (THQ), and hazard index (HI) values. Results: According to the results, the concentrations of Cr, Se, Ca, Fe, Mo, Mn, and Mg in soybean seeds were 0.034-170.88 mg/kg, 0.21-243.79 mg//kg, 2.50-33.37 mg/kg, 0.05-0.86 mg/kg, 0.071-203.57 mg/kg, 0-0.47 mg/kg, and 2.69-19.31 mg/kg, respectively. The ashing method had a better performance in determining Ca, Fe, Mo, Mn, and Mg concentrations than the wet digestion method. The THQ rates were below 1 for the three varieties of each mineral element, but the HI values of variety 2 and variety 3 were higher than 1 in both methods. Conclusion: Furthermore, continuous monitoring of the soybeans' mineral and heavy metal contents seems necessary.