14C示踪法研究多溴联苯醚在土壤和土壤动物中的转化与归趋

多溴联苯醚（PBDEs）是广泛应用的阻燃剂，由于其具有持留性和生物毒性，已成为环境科学研究中倍受关注的持久性有机污染物(POPs)。全面了解PBDEs环境行为与归趋，是科学评价其环境安全性的基础。本项目拟以典型PBDEs为对象，在研究并建立14C-PBDE标记合成方法的基础上，综合运用核素示踪和现代波谱技术，从质量平衡和示踪动力学角度综合考量PBDEs在土壤中的可提态残留、结合态残留和矿化动态规律，阐明14C-PBDEs在土壤中的化学和生物降解转化规律及可能的机制。同时，系统研究14C-PBDEs在模式动物（蚯蚓）中的蓄积和消减规律及其与赋存形态的关系，通过鉴定代谢物组成，推断不同PBDE同系物的代谢转化机制。旨在更系统深入地认识PBDEs在环境中的归趋，为更客观地评价PBDEs的环境风险性提供理论依据和技术支持，并为其他POPs的同类研究，提供可资借鉴的研究思路与方法。

Polybrominated diphenyl ethers (PBDEs) are a class of widely used brominated flame retardants with increasing environmental concerns due to their persistence and potential harms. Full understanding about the environmental fate of PBDEs is necessary for an accurate prediction about their risks. In this project, we proposed to establish an effective carbon-14 labeled synthesis method for typical PBDE congeners (BDE47，BDE99， BDE154 and BDE209) and the obtained 14C-PBDEs are expected to be further applied to completely demonstrate the dynamics of extractable residues, bound residues and mineralization of PBDEs in soil system. Facilitating the modern analytical methods (chromatography separating and mass spectrometry) by radioisotopic tracing, the study would be able to completely elucidate the abiota and biota transformation of PBDEs using mass balance concept and tracer kinetics modeling. The bioaccumulation and elimination of PBDEs in soil animal and their dependence on the formation of bound residues and specific congeners are also proposed to be studied using earthworm as the testing organism. The results obtained in this study would be of important implications for a better understanding about the long-term fates of PBDE-derived compounds in soil and soil animal, which will help us to make a more accurate prediction about environmental risks for PBDEs and make more reasonable environment quality criteria. Moreover, the methodology established in this study could provide valuable references and experiences for similar studies on other POPs.