Organophosphate flame retardants (OPFRs) in water and sediment: Occurrence, distribution, and hotspots of contamination of Lake Shihwa, Korea.

Contamination by organophosphate flame retardants (OPFRs) is an emerging concern in aquatic environments. Concentrations of 18 OPFRs were measured in water and sediments collected from the artificial Lake Shihwa. OPFR concentrations in sediments measured in this study were the highest reported worldwide, implying severe OPFR contamination. The highest concentrations of OPFRs were found in creeks taken near industrial complexes, and OPFR concentrations decreased with increasing distance from creeks to inshore or offshore lake waters. On-going OPFR contamination by wastewater treatment plant (WWTP) discharge was evidenced by the clear decrease in OPFRs in water samples collected moving away from WWTP outfall. TBEP and TEP were dominant in water samples, while TDCPP and TCPP were dominant in sediment samples. Differences in contamination profiles with sample matrices are likely due to hydrophobicity of individual OPFRs. Non-parametric multidimensional scaling ordination showed that OPFR contamination was affected by pollution inflow and proximity to industrial complexes.