科研进展

【论文题目】Biotransformation kinetics and pathways of 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) and its hydroxylated and methoxylated derivatives (6-OH-BDE-47 and 6-MeO-BDE-47) in earthworms (Eisenia fetida)（2,2′,4,4′-四溴二苯醚（BDE-47）及其羟基化和甲氧基化衍生物（6-OH-BDE-47 和 6-MeO-BDE-47）在蚯蚓（Eisenia fetida）体内的生物转化动力学和途径）

【作者】Xuehui Xu⁎, Guoqing Wang, Yuejin Li, Yufei Zhang（许学慧*，王国庆，李跃进，张宇飞）

【期刊名称和年（卷、期）】Science of the Total Environment 855 (2023) 158934

【摘要】

【Abstract】As a class of persistent organic pollutant, polybrominated diphenyl ethers (PBDEs) and their hydroxylated and methoxylated derivatives (OH-PBDEs and MeO-PBDEs) have been widely detected in soil environments. However, studies on the bioavailability and transformation of PBDEs and their derivatives in soil organisms remain scarce. In this study, a detailed kinetic investigation on the accumulation and biotransformations of BDE-47, 6-MeO-BDE-47 and 6-OH-BDE-47 in earthworms (Eisenia fetida) exposed to artificially contaminated soils was conducted. The uptake and elimination kinetics of BDE-47, 6-MeO-BDE-47 and 6-OH-BDE-47 by earthworms were in accordance with a onecompartment first-order kinetic model. The bioaccumulation factors (BAFs) followed the order 6-MeO-BDE-47 > 6-OH-BDE-47 > BDE-47. All three compounds could undergo step-by-step debromination to produce lower brominated analogs in earthworms. Both BDE-47 and 6-OH-BDE-47 could be transformed toMeO-PBDEs, whereas no transformation from6-OH-BDE-47 or 6-MeO-BDE-47 to PBDEs or fromBDE-47 and 6-MeO-BDE-47 toOH-PBDEs took place in the earthworms. Methoxylationwas proposed as a potential metabolic pathway to form MeO-PBDEs in earthworms, with the metabolic rates for the methoxylation of BDE-47 and 6-OH-BDE-47 being 27.7 and 5.1 times greater, respectively, than that of the debromination metabolism. The isomers of 6-MeO-BDE-47 and 6-OH-BDE-47 were formed via the addition ofmethoxy/hydroxy groups or via bromine shifts on benzene ring in the earthworms. This study provides comprehensive information for a better understanding of the accumulation and biotransformation of PBDEs and their derivatives in earthworms.

【Keywords】PBDEs; OH-PBDEs; MeO-PBDEs; biotransformation; kinetics; earthworm

【原文附件】见附件