Formation of chlorinated haloacetic acids by chlorination of low molecular weight compounds listed on pollutant release and transfer registers (PRTRs)

Abstract

Anthropogenic compounds accidentally released to the environment could be important precursors of disinfection byproducts (DBPs) in drinking water treatment processes. In this study, the haloacetic acid formation potentials (HAAFPs) of 155 anthropogenic compounds listed on the Japanese pollutant release and transfer register (PRTR) system were evaluated. The results showed that phenolic and aromatic amine compounds were important HAA precursors, and chlorinated phenols showed high HAAFPs (>400 μg/mgC). Moreover, trichlorfon and ethyl chloroacetate (HAAFP of 104.9 and 602.3 μg/mgC, respectively) were also important HAA precursors because of their ability to undergo hydrolysis. Although most anthropogenic compounds with high HAAFPs showed high chlorine consumptions, no clear correlation between HAAFPs and chlorine consumptions was found in this study. In addition, the quantitative structure-activity relationship (QSAR) approach was a useful tool for predicting the chlorine consumption of organic compounds but was not effective for predicting HAAFPs based on the information currently available. A scenario study assuming a hypothetical accidental release predicted that the release of 3,4-dichloroaniline (HAAFP of 407.6 μg/mgC) would lead to a violation of the current drinking water quality standards for HAAs in Japan.

Keywords: Haloacetic acids; Low molecular weight compounds; Pollutant release and transfer registers; Quantitative structure-activity relationships.