Health Risk Assessment of Heavy Metals (Arsenic and Cadmium) in Rice (Oryza sativa L.) Brands Imported to Iran: Using Monte-Carlo Simulation

Background: Rice contamination with heavy metals is one of the most common cases of environmental pollution. The purpose of this study was to investigate the concentration of heavy metals (arsenic and cadmium) in the most widely consumed rice brands imported to southern Iran and to assess the health risk of exposure to them for consumers. Methods: A total of 103 rice samples were selected from 10 brands imported from India during 2014-2018. Heavy metal concentrations were measured by dry ash method using atomic absorption spectrometer (GBC model SavantAA). After determining the concentration of heavy metals in rice samples, health risk assessment was performed using the Monte-Carlo simulation technique. Results: The concentrations of arsenic and cadmium were 94.3 ± 34.1 and 11.3 ± 6.5 mg/kg, respectively. The values of non-carcinogenic risk index (hazard quotient) of cadmium and arsenic were 0.017 and 0.489, respectively. The average carcinogenic risk index for arsenic was 1.7E10-4, which is higher than the standard range (10-4 to10-6). Conclusion: Consumption of imported rice carries a risk of arsenic-induced carcinogenesis. Consumption of contaminated rice with heavy metals, especially arsenic, can pose potential health risks to the consumer population. Therefore, special attention should be paid to contaminated rice and special interventions should be made to reduce arsenic in imported rice.