ABSTRACT
Brominated haloacetic acids (HAAs) are much more cytotoxic and genotoxic than chlorinated one, yet little information is available for their organic precursors. In the present study, 8 water samples were collected in East China: 2 from lakes, 2 from rivers, 2 from reservoirs, a well and a mountain spring. Dissolved organic carbon (DOC), UV absorbance at 254 (UVA), specific UVA (SUVA) and chlorophyll a (Chl-a) were determined in raw water samples; formation of 9 HAA species as well as bromine substitution factor (BSF) were measured in chlorinated water samples. Results showed that water samples located in city generally contained higher levels of DOC (6.4-12.2mg/L) and UVA (0.124-0.194/cm), while those in the country side, low DOC (2.4-5.9mg/L) and UVA (0.061-0.109/cm) levels were observed. Negative relationship (p<0.01) was found between SUVA values and Chl-a levels. Among 9 HAA species, 4 brominated HAA were detected. As for BAA and DBAA (i.e. Br-HAAs), their yields (µg/L) were significant related (p<0.05) with DOC; In terms of BCAA and BDCAA (i.e. ClBr-HAAs), they were not only related with DOC, but also with UVA. These two results were quite different from DCAA and TCAA (Cl-HAAs), whose yields (µg/mg C) were only correlated with SUVA values, suggesting that precursors of Cl-HAA, Br-HAA and ClBr-HAA were different from each other, and their aromaticity/hydrophobicity may be in the order of Br-HAA
