Risk assessment of dietary perchlorate exposure in typical areas of fireworks manufacturing in China using a...

Perchlorate can disrupt the production of thyroid hormones, impact metabolism, and even affect the cognitive development of infants and toddlers. Typical areas of fireworks manufacturing might face severe perchlorate pollution due to perchlorate is an important raw material. But related study has not been reported. We assess the risk caused by perchlorate and identify the critical exposure pathways for different age/gender groups in typical area of fireworks manufacturing. Liuyang city, a major fireworks manufacturing center in China, was selected as study region. Perchlorate concentrations were measured in 230 local food samples from Liuyang using LC/MS/MS. Risks for different age/gender groups were estimated using a perchlorate intake model. The detection rate of perchlorate in samples from all eight food groups, including vegetables, fruits, meat, seafood, egg, cereal, beans, and drinking water was 100%, and the perchlorate concentrations were higher than those reported in the United States, Canada, South Korea, Kuwait, and other regions of China. Liuyang residents are currently facing an extremely high perchlorate dietary exposure risk, with the mean Estimated Daily Intakes (EDIs) approximately 6-49 times higher than US EPA's recommended reference dose (RfD, 0.7 μg/kg bw/day), and 14-115 times higher than the tolerable daily intake (TDI, 0.3 μg/kg bw/day) established by EFSA. Breast milk and drinking water are identified as the primary exposure pathways for infants and toddlers under the age of two, contributing 44-86% and 13-41% to their total exposure, respectively. For individuals > two years, vegetable consumption (constituting 54-66% of exposures) and ingestion of drinking water (constituting 23-32% of exposures) represent the chief exposure routes. The Hazard Quotient (HQ) values for Liuyang City residents all exceed 2, indicating an extremely high non-carcinogenic risk associated with perchlorate. Scientific and systematic perchlorate pollution control measures should be taken by local government.