Characterization of polybrominated dibenzo-p-dioxins and dibenzofurans in different atmospheric environments

Few studies have measured polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs) in the atmosphere. In this study, four categories of atmospheric environments, including rural (Kengting national park, Taitung county, and Yilan county), urban (north Kaohsiung city and south Taichung city), industrial (Lin-hai industrial park), and science park(Hsinchu science park) areas were investigated for their characteristics of 2,3,7,8-substituted PBDD/F and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). The elevated PCDD/F I-TEQ concentrations and higher ratio of PCDFs to PCDDs in the industrial areas reveal that the metallurgical facilities, including sinter plants, electric arc furnaces, secondary aluminum smelters, and secondary copper smelters, significantly influence their surrounding atmospheric environments. The mean PBDD/F concentrations in the atmosphere of the rural, urban, industrial, and science park areas were 11, 24, 46, and 95 fg/Nm(3), respectively, while the corresponding mean TEQ concentrations were 2.7, 6.4, 12, and 31 fg TEQ/Nm(3), respectively. The significantly high correlation (r = 0.85, P=0.034)found between the PBDD/F and PCDD/F concentrations in the atmospheres of the industrial areas reveals that the metallurgical facilities are also the most likely PBDD/F emission sources in the industrial areas. The PBDD/F concentration in the science park area Was similar to 2-fold higher than that in the industrial areas, whereas PCDD/F I-TEQ concentration in the area was only 23% of that in the industrial areas. The elevated PBDD/F concentrations in the science park areas may be attributed to the use of polybrominated diphenyl ethers as brominated flame retardants in the electrical and electronics industries, which contribute to direct PBDD/F emissions into the environment. PBDFs were all much more dominant than PBDDs in the atmosphere, and their mass fractions increase with PBDD/F concentrations.