Concentrations of seven indicator polychlorinated biphenyls (Ʃ7PCBs) and eight predominant polybrominated diphenyl ethers (Ʃ8PBDEs) were examined in outdoor dust samples collected from some representative areas in northern Vietnam, including a core urban area of Hanoi City, an industrial park in Thai Nguyen Province, and a rural area in Bac Giang Province. Levels (median and range) of Ʃ7PCBs and Ʃ8PBDEs in our dust samples were 2.8 (0.028–22) and 11 (0.55–52) ng/g, respectively. Concentrations of PCBs and PBDEs in the urban and industrial dust samples were significantly higher than those measured in the rural ones, suggesting the role of urbanization-industrialization processes on the emission of these pollutants. PCBs exhibited specific profiles in the industrial dusts with significant proportions of low-chlorinated congeners such as CB-28 and CB-52, while the remaining samples were more contaminated by heavier compounds such as CB-118, CB-138, and CB-153. For PBDEs, BDE-209 was the most predominant congener in all the samples. Emission souces of PCBs and PBDEs in our dust samples were estimated to be household, traffic, and industrial activities. Human exposure to PCBs and PBDEs in outdoor dusts was estimated, implying relatively low health risk.
The Role of Bacteria on the Breakdown of Recalcitrant Polychlorinated Biphenyls (PCBs) Compounds in Wastewater