Distribution of organophosphorus flame retardants in sediments from the Pearl River Delta in South China

Twelve organophosphorus flame retardants (PFRs) were identified in the sediments and the sediment core collected from the rivers and the estuary in the Pearl River Delta, with the aim of investigating their spatial and vertical distributions. The concentrations of PFRs ranged from 8.3 to 470 ng/g dry weight with high levels of PFRs in the urban area and the e-waste recycling region. Generally, TPhP, TCPP, TEHP, TCEP, and TBEP were the dominant compounds of the PFRs, the composition of which varied across the different regions, reflecting the different sources of PFRs. In the estuary, the PFRs mainly derived from the Xijiang River and the Shunde sections. Increased concentrations of halogen-containing PFRs have been observed in the upper layers of the sediment core. Conversely, relatively high concentrations of halogen-free PFRs were observed in the lower layers of the sediment core, indicating different usage patterns or environmental behaviors between the halogen and the non-halogen PFRs in the study area. (C) 2015 Elsevier B.V. All rights reserved.