Atmospheric PCDD/Fs in southeastern China

Air samples were collected simultaneously at Guiyu (an electronic waste recycling site), three urban sites in Hong Kong and two urban sites in Guangzhou, southeast China on August 20, 2004 and January 24, 2005, respectively. Seventeen congeners of PCDD/Fs (polychlorinated dibenzo-p-dioxins dibenzofurans) were measured. The results showed that the concentration of PCDD/Fs in Guiyu was 6,721 fg/m³, which was 1.5 times of Guangzhou and 3.1 times of Hong Kong sites. TEQ (total toxic equivalent) of Guiyu, Guangzhou and Hong Kong air samples were 598, 202 and 137 fg I-TEQ/m³, respectively. A clear seasonal variation of PCDD/Fs in the air was found in both Guangzhou and Hong Kong sites. The concentration of 2,3,7,8-TCDD (2,3,7,8-Tetrachlorodibenzodioxin) in Guiyu was 54 fg/m³, higher than the whole year standard of 30 fg/m³ imposed by USA (Indiana, Kansas and Washington). This was primarily due to the incomplete combustion of e-wastes (e.g., plastic chips, wire insulations, PVC (polyvinyl chloride polymer) materials and metal scraps). Copyright © 2013 David Publishing Company.