Abstract
| - The presence of chlorinated and brominated compoundsin electronic waste (EW) results in the formation ofpolychlorinated dibenzo-p-dioxins and dibenzofurans(PCDD/Fs) and polybrominated dibenzo-p-dioxins anddibenzofurans (PBDD/Fs) during the EW dismantling process.In this study, we investigated the dioxins present inambient air around the EW dismantling area Guiyu inGuangdong, China. Atmospheric PCDD/F (tetra to octa)abundances and toxic equivalent (TEQ) values were64.9−2365 pg/m3 and 0.909−48.9 pg of W-TEQ/m3, respectively;these are the highest documented values of thesecompounds found in ambient air in the world. PBDD/Fs(eight 2,3,7,8-substituted congeners) were also found at highpollution levels (concentrations of 8.124−61 pg/m3 and1.6−2104 pg of I-TEQ /m3). Profiles of the 2,3,7,8-PCDD/Fhomologues in the air of Guiyu differed from typical urbanair patterns reported in the literature, and the concentrationof homologues increased with the chlorination degree of2,3,7,8-PCDD/Fs except for OCDF. The severe dioxinpollution present in Guiyu substantially influences theadjacent area of Chendian, where atmospheric PCDD/Fand 2,3,7,8-PBDD/F levels are higher than those of commonurban areas in the world. Our tentative inhalation riskassessment showed that residents in Guiyu are at a highrisk of exposure to dioxins. The total PCDD/F intakedoses far exceed the WHO 1998 tolerable daily intakelimit of 1−4 pg of W-TEQ kg-1 day-1.
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