Organic phosphorus flame retardants and bisphenols in municipal wastewater, runoff and drinking water in a sub-arctic city.

Organic phosphorus flame retardants (OPFRs) and bisphenols (BPs) originate in a range of consumer-based products, building materials and vehicles. With expanding human activities in the warming Arctic, these compounds may become more prevalent in remote regions which can harm the local ecosystems. The goal of this research was to assess the occurrence and chemical concentration of OPFRs and BPs in waste-, surface and drinking waters in the capital region of Reykjavík, Iceland (64°N, 244 thousand inhabitants). OPFRs were detected in most municipal wastewater, storm drain and detention pond samples during warm and cold seasons. Among the eight targeted high-volume production OPFRs, Tris(2-chloroisopropyl) phosphate (TCIPP) measured in the highest concentrations (maximum 650 ng/L), followed by Tris(2-chloroethyl) phosphate (TCEP; <350 ng/L), Triphenyl phosphate (TPhP, <220 ng/L), Tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) and Triethyl phosphate (TEP), which peaked around 100 ng/L in surface waters. Among the six BPs observed, the heat tolerant Bisphenol S (BPS) and its novel derivative BPS-MAE, were most frequently detected both in waste- and surface waters, at concentrations <17 ng/L. OPFRs and BPs were rarely detected in the groundwater source used for drinking. The annual wastewater plant emissions from a 40 km2 catchment servicing ∼100 000 residents were estimated as 0.7-1 kg/year for each of the commonly detected OPFRs, except for TCIPP (∼20 kg/yr). Stormwater was estimated to contribute less to the annual urban loading than municipal wastewater, because of a lower annual volume and lower concentrations (TCIPP, BPS-MAE). These initial results suggest that TPhP discharged from a preliminary wastewater treatment plant may pose medium risk to aquatic ecology. Untreated urban stormwater, particularly from light industrial catchments, can contribute to medium risk of TCEP and TDCIPP, and potentially high risk of TPhP. Therefore, stormwater should not be neglected as a significant pathway of OPFRs and BPs to aquatic environments.