The occurrence of haloanisoles as an emerging odorant in municipal tap water of typical cities in China

Abstract

In this study, occurrence of the haloanisoles odorous compounds in tap water of Chinese cities, were investigated by solid-phase microextraction (SPME)-GC/MS analysis. This study revealed the occurrence of four kinds of haloanisoles in 22 cities of China in both summer and winter. Except 2,4,6-tribromoanisole (2,4,6-TBA), all studied haloanisoles showed higher frequency of detection. 2,3,6-Trichloroanisole (2,3,6-TCA) and 2,3,4-trichloroanisole (2,3,4-TCA) showed higher occurrence concentration; however, the relative odor values of them was lower. These values of 2,4,6-TBA and 2,4,6-trichloroanisole (2,4,6-TCA) in all samples were greater than zero in both summer and winter, indicating the odor from haloanisoles could be felt by human noise. This study further showed that Beijing exhibited most serious occurrence of haloanisoles that were depended on the season and drinking water distribution system (country and city). From this study, it was confirmed that haloanisoles was important taste and odor compounds in tap water of China. Based on the survey of occurrence of halophenol and residual chlorine, the possible source for the formation of haloanisoles in tap water was discussed. Furthermore, several suggestions on control the haloanisoles odor in drinking water treatment plant and water distribution system were provided.