Pollution Characteristics and Risk Assessment of Chlorate and Perchlorate in Tea from Anhui Region, China
This study investigated the pollution characteristics of chlorate and perchlorate in tea from Anhui region and assessed the health risks associated with tea consumption. A total of 132 tea samples, including green tea (n=89), black tea (n=30), yellow tea (n=10), and white tea (n=3), were collected from major tea-producing areas. Chlorate and perchlorate levels were quantified using isotope dilution liquid chromatography-tandem mass spectrometry. Chlorate was detected in 15.9% of samples, with concentrations ranging from not detected to 0.040 mg·kg−1, and no samples exceeded the regulatory limit. Perchlorate was detected in 100% of samples, with concentrations ranging from 0.011 to 1.611 mg·kg−1, and 2.3% of samples exceeded the limit. Pollution characteristics analysis revealed that perchlorate levels were significantly correlated with tea type and geographical origin, with environmental contamination in tea-growing areas being the primary determinant. A significant positive correlation was also observed between chlorate and perchlorate levels. Health risk assessments were conducted for the general tea-consuming population, sub-groups loyal to specific tea types (green and black tea), and sub-groups preferring local tea from high-pollution regions (Lu'an City and central Anhui). Assessments were based on mean and 95th percentile (P95) exposure levels. For chlorate, the maximum hazard quotient (HQ) was 0.003, far below 1, indicating negligible risk. For perchlorate, all HQ values were below 1, regardless of tea type or region, based on both mean and P95 levels, using the Chinese provisional tolerable daily intake (tTDI). However, perchlorate contamination in central Anhui, particularly Lu'an City, warrants continued monitoring due to elevated levels and occasional exceedances.