Occurrence and risk evaluation of organophosphorus flame retardants in two urban rivers in Yangtze River Delta

Abstract

The occurrence and profiles of organophosphate flame retardants (OPFRs) were investigated in the Huangpu and Shiwuli Rivers, two urban rivers in the Yangtze River Delta, China. The total concentrations of OPEs were found at part-per-trillion ranges, with average concentrations that ranged from 424 to 1.84 × 103 ng L-1 for Huangpu River and 221 to 1.84 × 103 ng L-1 for Shiwuli River. Three chlorinated OPFRs including tris(chloroethyl) phosphate (TCEP), tris(2-chloroisopropyl) phosphate (TCIPP), and tris(1,3-dichloroisopropyl) phosphate (TDCIPP) were the most abundant compounds among the investigated OPFRs, accounting for 90.6-99.8% of total concentrations. In Huangpu River, the OPFR concentrations were significantly higher in the dry season than in the wet season which indicates obvious seasonal variation. Chlorinated OPFR concentrations differed significantly between upstream and downstream reaches of the Shiwuli River, as the result of geographic features and wastewater discharge. Estimated risk was calculated to compare predicted no-effect concentrations (PNEC) to observed concentrations of OPFRs. The results indicated no significant acute adverse effects of OPFRs in the two urban rivers for fish, daphnia, or algae.