Halogenated flame retardants contamination in Chinese teas: levels, sources, and human exposure

This study investigated the occurrence of polybrominated diphenyl ethers (PBDEs), novel brominated flame retardants (NBFRs), and dechlorane plus (DP) in seven categories of tea samples collected from major tea-producing regions across China. Halogenated flame retardants (HFRs) were detected in all samples, with total concentrations ranging from 0.14 to 83.79 ng/g dry weight (dw) (mean: 19.39 ng/g dw). Decabromodiphenylethane (DBDPE; n.d.-61.91 ng/g dw) and BDE-209 (n.d.-32.44 ng/g dw) emerged as the dominant contaminants. Geographical analysis revealed significant regional disparities in HFR contamination, with the highest levels observed in Zhejiang and Guangdong provinces. Key factors influencing HFR accumulation included source distribution, fermentation processes, storage duration, and total organic carbon (TOC) content. Significant correlations between PBDEs and NBFRs suggested their similarly environmental behaviors (p < 0.05). Risk assessment indicated that dietary exposure to HFRs through tea consumption poses minimal health risks to children and adults. These findings enhance understanding of HFR distribution in tea ecosystems and support evidence-based food safety strategies.