The concentration and prevalence of aflatoxins and ochratoxin A in imported rice (Oryza sativa) samples from Iranian market: a probabilistic dietary risk assessment

This investigation aimed to measure the concentrations of total aflatoxin (AFT), aflatoxin B-1 (AFB(1)), and ochratoxin A (OTA) in imported rice samples to Iran and conduct a probabilistic health risk assessment for consumers. Three thousand seven hundred fifty-one imported rice samples were randomly collected from March 2022 to April 2024. The AFT, AFB(1), and OTA concentrations were analysed using high-performance liquid chromatography with a flame ionisation detector (HPLC-FID) and an ultraviolet detector (HPLC-UV). The ranking of mycotoxins based on mean concentration in rice was as follows: AFT (3.996 +/- 6.925 mu g/kg) > AFB(1) (2.648 +/- 5.746 mu g/kg) > OTA (0.088 +/- 0.847 mu g/kg). The prevalence of these mycotoxins was found to be AFT present in 897 out of 3,710 samples (24.18%), AFB1 in 657 samples (17.52%), and OTA in 40 samples (1.07%). Significant correlations were observed between AFT and AFB(1) (C: 0.96, p-value < 0.001), AFT and OTA (C: 0.28, p-value < 0.001), and AFB(1) and OTA (C: 0.15, p-value < 0.001). The 95th percentile of the Margin of Exposure (MOE) for AFB1 in adult and child consumers was 0.930 and 0.270, respectively, while the Hazard Quotient (HQ) for OTA in adults and children was 0.030 and 0.100, respectively. The estimated cancer risk percentages for AFB(1) in rice were 22.220 for adults and 43.500 for children. Overall, consuming imported rice containing AFT, AFB(1), and OTA does not pose a significant non-carcinogenic risk to consumers' health. However, the carcinogenic risk in Iran is higher than in other countries. Therefore, it is recommended that more effective and continuous monitoring programmes be implemented to ensure the quality of imported rice.