Passive Air Sampling of Polychlorinated Biphenyls, Organochlorine Compounds, and Polybrominated Diphenyl Ethers Across Asia

Abstract

Asia is of global importance economically, yet data on ambient persistent organic pollutant levels are still sparse for the region, despite international efforts under the Stockholm Convention to identify and reduce emissions. A large-scale passive air sampling survey was therefore conducted in Asia, specifically in China, Japan, South Korea, and Singapore. Polyurethane foam disks were deployed simultaneously at 77 sites, between Sept 21 and Nov 16, 2004, and analyzed for polychlorinated biphenyls (PCBs), organochlorine compounds (hexachlorobenzene (HCB), dichlorodiphenyltrichloroethanes (DDTs), chlordane), and polybrominated diphenyl ethers (PBDEs). The meteorological conditions prevailing in the region at this time facilitated the assessment of local/regional differences in atmospheric emissions, because large-scale advection effects due to monsoons or dust storms did not occur. Air concentrations estimated assuming an average sampler uptake rate of 3.5 m3/day ranged as follows (pg m(-3)): PCBs, 5-340; HCB, 10-460; DDTs, 0.4-1800; chlordanes, 1-660; PBDEs, < 0.13-340. South Korea and Singapore generally had regionally low concentrations. Elevated concentrations of PCBs, DDTs, and HCB occurred at sites in China, higher than reported in a similar recent sampling campaign in Europe. Chlordane was highest in samples from Japan (which also had elevated levels of PCBs and DDTs) and was also elevated in some Chinese locations. PBDE levels were generally low in the region.

Levels and Vertical Distributions of PCBs, PBDEs, and OCPs in the Atmospheric Boundary Layer: Observation from the Beijing 325-m Meteorological Tower

“…Dependence of sampling rates on wind speed and temperature. (10). Also it is consistent with the viewpoint that atmospheric PBDE levels in China were generally low owing to the limited use of PBDE products (10).…”

“…Therefore, PAS devices have been successfully used on various geographical scales from local (8) to continental (9) and global (3). In 2004, a large-scale PAS survey was conducted across Asia including China (10). However, field monitoring data in China are still very scarce, especially regarding atmospheric POPs.…”

Polybrominated Diphenyl Ethers vs Alternate Brominated Flame Retardants and Dechloranes from East Asia to the Arctic

“…Concentrations in the Canadian Arctic were 0.78À48 pg m À3 for ∑ 15 PDBEs in 2002À2003 24 which are, again, significantly higher than in the present study. Jaward et al 25 reported concentrations in the East Asian terrestrial atmosphere mainly in the low pg m À3 range which are similar to the concentrations observed in the East Asian samples in this study. The observed concentrations in the Arctic are similar to those recently observed in Greenland and East Greenland Sea 20,26 and the Southern Ocean 17 representing remote concentrations derived from LRAT.…”

Hexachlorobenzene sources, levels and human exposure in the environment of China

“…HCB was detected in all the sampling sites, which implies its long-range transport potential and persistence. Jaward et al (2005) studied the spatial distribution of HCB concentrations across Asia by passive sampling survey using PUF discs in 2004, which revealed that air HCB levels in China showed much variation, increasing gradually from southwest to northeast (Table 2). It is different from the uniform distribution found in South Korea (14-95 pg/m 3 ), Japan (26-136 pg/m 3 ) (Jaward et al, 2005) and Europe (1.4-8.9 pg/m 3 ) (Jaward et al, 2004), which indicated that there were some primary emission sources of HCB in China.…”

“…The atmospheric concentrations are now fairly uniform, varying by less than an order of magnitude at background sites. However, highest HCB air concentrations were still found in historical source regions, indicating that there are some ongoing primary or secondary emissions (Jaward et al, 2005). HCB concentrations in background soils were strongly influenced by source region and soil organic matter content (Meijer et al, 2003a;Valle et al, 2005).…”