Simulation research on the natural degradation process of PBDEs in soil polluted by e-waste under increased concentrations of atmospheric O3

Abstract

There have been increased concerns regarding the effect of polybrominated diphenyl ethers (PBDEs) on the environment. These compounds are widely utilized by the electronics industry and also function as fire retardants. More data on the basic characteristics of PBDEs are needed to better understand and used to describe their environmental fate. The aim of this study was to investigate the degradation of BDE-209 with different degrees of bromination under changes in the atmospheric environment. BDE-209 was able to be removed quickly due to the strong oxidizing ability of ozone in the atmosphere environment. Less-brominated BDEs, ranging from BDE-28 to BDE-183, were formed progressively, and the reaction of ozone gradually occupied the main position along with an increase in ozone flow time. Degradation reaction rates of PBDEs increased with increasing ozone concentration but decreased with increasing soil depth. Under UV-irradiation, BDE-209 was quickly transformed into less-brominated BDEs and the photodegradation reactions were faster than solar irradiation. The conditions of high ground temperature in the summer and alkaline soil were both contributors to the degradation of PBDEs. These results could facilitate the improvement of waste treatment designs and lead to better predictions of the outcome of PBDEs in the environment.