Levels and congener profiles of particle-bound polybrominated dibenzo-p-dioxins/furans (PBDD/Fs) in ambient air around Guangzhou, China.

The mean particulate polybrominated dibenzo-p-dioxins/furans (PBDD/Fs) levels for Guangzhou were in the range of 225-2244 fg/m(3) and showed the spatial trend of background < suburb areas < urban area < industrial area, suggesting the industrial and urban sources of PBDD/Fs. The most abundant congeners were 2,3,7,8-TBDF, 1,2,3,7,8-PeBDF and 2,3,4,7,8-PeBDF. The mean toxicity equivalency quantities (TEQs) of PBDD/Fs were in the range of 89.3-456 fg I-TEQ/m(3) for Guangzhou, which were several times higher than that of the background area (49.1 fg I-TEQ/m(3)). The rough inhalation risk evaluation showed that the residents in Guangzhou were in relatively higher exposure levels of PBDD/Fs.