Distribution and Characterization of Higher Chlorinated Benzenes in Outdoor Dust Collected from a Fast Developing City in North China

Five higher chlorinated benzenes (CBs), include hexachlorobenzene (HCB), pentachlorobenzene (PeCB) and three isomers of tetrachlorobenzens, were analyzed in 20 outdoor dust samples collected from a fast developing city, Xinxiang. Only HCB was detected in all outdoor dust samples. The dominate part of the CBs residue in most samples was HCB and the mean HCB concentration (4.13 ng/g dry weight) in this study was in the range of global background soil HCB levels (ranging from 0.010 to 5.20 ng/g dry weight). The higher ratios of HCB/PeCB in the outdoor dust samples in the present study indicate that pesticide application may be an important source of HCB in China.