Cadmium, Arsenic and Mineral Nutrients in Rice, and Potential Risks for Human Health in South China

Abstract Rice (Oryza sativa L.) is one of the most important staple food crop worldwide. For people fed on rice, toxic elements cadmium (Cd) and arsenic (As) and mineral nutrients in rice are pivotal to evaluate potential risks of harmful element intake and malnutrition. We collected rice samples of 208 cultivars (83 inbred and 125 hybrid) from fields in South China, and determined Cd, As, As species, and mineral elements in brown rice. Histochemistry analysis shows that Cd and As in brown rice were 0.26 ± 0.32 and 0.21 ± 0.08 mg·kg− 1, respectively. Inorganic As (iAs) was the dominative As species in rice. Brown rice Cd and iAs in 35.1% and 52.4% of the 208 cultivars exceeded rice Cd and iAs limits. Significant variations of rice subspecies and regions were found for Cd, As and mineral nutrients in brown rice (P < 0.05). Inbred rice has lower As uptake and more balanced mineral nutrition than hybrid species. Significant correlation was observed between Cd, As versus mineral elements like Ca, Zn, B and Mo (P < 0.05). Health risk assessment indicates that high risks of Cd intake and malnutrition, in particular to Ca, protein and Fe, can be caused by rice consumption in South China.