Chlorate in foodstuffs from south China and its implication for human exposure

Chlorate, mainly used in the production of fireworks, herbicides and other products, is an inorganic pollutant, which easily dissolves in water and is difficult to degrade. Chlorate has a potential toxic risk to the thyroid function, kidneys, and blood system, which could pose a potential threat to human health. However, studies focusing on human exposure to chlorate are scarce, especially via food consumption. This study aimed to investigate the concentrations of chlorate in six types of foods (n = 531) from south China, and evaluate potential exposure risks for local residents. The detection rates of chlorate in all six types of foods were greater than 50 %, indicating the ubiquitous occurrence of chlorate in foods. Among the six types of foods, vegetables exhibited the highest concentrations of chlorate (p < 0.05), mainly attributed to the direct exposure to the environment compared with other foods. The hazard quotient (HQ) values by using EFSA reference dose (RfD) of chlorate via foods and water consumption existed greater than 1 in different age groups, indicating a potential health risks to human in south China.