Distribution and Leaching Behavior of Organophosphorus and Brominated Flame Retardants in Soil in Chengdu

A total of 29 surface farmland soil samples were collected to investigate the spatial distribution and composition characteristics of 13 organophosphorus flame retardants (OPFRs), 11 PBDEs, and 8 novel brominated flame retardants (NBFRs) in Chengdu, China. The OPFRs were widely detected in the farmland soil with concentrations ranging from 2.92 to 160 ng/g dry weight (dw). BDE-209 was found with a concentration range of n.d. to 50.4 ng/g dw, and was the main PBDEs congener accounting for 90% of ΣPBDEs in the surface farmland soil. In the case of NBFRs, only TBB and BTBPE were detected in the farmland soil from rural area of Chengdu. No significant difference was found in the OPFRs concentrations among Xindu, Longquan, Shuangliu, Wenjiang, and Pixian districts (p > 0.05), but the maximum concentration of OPFRs from Xindu district was higher than those in other studied areas, which might be due to furniture production in this area. Leaching experiment showed the concentration of most of investigated OPFRs in two kinds of soils decreased with the increasing of soil depth, and DOM level could have an influence on the leaching behavior of OPFRs, but to a certain degree. More importantly, TCEP exhibited stronger mobility than TCPP in soil, indicating it might more easily migrate from soil to groundwater.