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 existed in the farmland soil, with concentrations ranging from 2.92 to 160 ng/g dry weight (dw). BDE-209 was the main PBDEs congener in the surface farmland soil accounted for 90%, with concentrations ranging from n.d. to 50.4 ng/g dw. 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 resulted in furniture production in this area. Leaching experiment showed most investigated OPFRs levels in two soils decreased with the increasing of soil depth. There was no obvious difference in leaching behavior of the OPFRs in laterite and loess, but higher content of DOM prevented the OPFRs from leaching out in soil, and TCEP have more mobility than TCPP, which might have more potential pollute groundwater.