Occurrence of organophosphate flame retardants in drinking water from China.

Several organophosphate flame retardants (OPFRs) have been identified as known or suspected carcinogens or neurotoxic substances. Given the potential health risks of these compounds, we conducted a comprehensive survey of nine OPFRs in drinking water in China. We found total concentrations of OPFRs in tap water ranging from 85.1 ng/L to 325 ng/L, and tris(2-butoxyethyl) phosphate (TBEP), triphenyl phosphate (TPP), and tris(2-chloroisopropyl) phosphate (TCPP) were the most common components. Similar OPFR concentrations and profiles were observed in water samples processed through six different waterworks in Nanjing, China. However, boiling affected OPFR levels in drinking water by either increasing (e.g., TBEP) or decreasing (e.g., tributyl phosphate, TBP) concentrations depending on the particular compound and the state of the indoor environment. We also found that bottled water contained many of the same major OPFR compounds with concentrations 10-25% lower than those in tap water, although TBEP contamination in bottled water remained a concern. Finally, we concluded that the risk of ingesting OPFRs through drinking water was not a major health concern for either adults or children in China. Nevertheless, drinking water ingestion represents an important exposure pathway for OPFRs.