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Abstract: 57 pairs of air samples (gas and particle phases) were collected using a high volume air sampler in a typical city of Northeast China. Brominated flame retardants (BFRs) including 13 polybrominated diphenyl ethers (PBDEs, including BDEs 17, 28, 47, 49, 66, 85, 99, 100, 138, 153, 154, 183, and 209) and 9 alternative BFRs (p-TBX, PBBZ, PBT, PBEB, DPTE, HBBZ, γ-HBCD, BTBPE, and DBDPE) were analyzed. The annual average total concentrations of the 13 PBDEs and the 9 alternative BFRs were 69pg/m3 and 180pg/m3, respectively. BDE 209 and γ-HBCD were the dominant congeners, according to the one-year study. The partial pressure of BFRs in the gas phase was significantly correlated with the ambient temperature, except for BDE 85, γ-HBCD and DBDPE, indicating the important influence of ambient temperature on the behavior of BFRs in the atmosphere. It was found that the gas–particle partitioning coefficients (logKp) for most low molecular weight BFRs were highly temperature dependent as well. Gas–particle partitioning coefficients (logKp) also correlated with the sub-cooled liquid vapor pressure (logPL o). Our results indicated that absorption into organic matter is the main control mechanism for the gas–particle partitioning of atmospheric PBDEs. [Copyright &y& Elsevier]

Abstract: Twenty-eight surface sediment samples and one sediment core were analyzed for 21 organochlorine pesticides (OCPs), in order to provide extensive information of distribution, sources, pollution history and ecological risk of these OCP compounds in Daling River area, China. The results showed that hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethanes (DDTs) were the most frequently detected contaminants in the surface sediment samples with concentrations (in ngg−1 dry weight (dw)) from 1.1 to 30 and from 2.2 to 45, respectively. Analysis of variance showed significant (P<0.05) differences between HCHs and DDTs residues in surface sediment sampled from the various locations. Residues of HCHs and DDTs in sediment core (in ngg−1 dw) ranged from 2.1 to 18 and 9.1 to 53, respectively. The temporal trends of HCHs and DDTs concentrations in the sediment core were affected by application history, emission and soil residues. Compositional analysis of HCHs and DDTs indicated that new sources were lindane and dicofol mainly due to agricultural activities. Additionally, based on the available sediment quality guidelines, slight potential health risks of DDTs may exist to benthic organisms in Daling River and Bohai Sea. [Copyright &y& Elsevier]

Abstract: Air samples were collected using a HiVol air sampler for 24 hours every week from September 2008 to August 2009 in the city of Dalian, a typical coast city in Northeast China. 12 polybrominated diphenyl ethers (PBDEs) congeners (BDE-17, -28, -47, -66, -85, -99, -100, -138, -153, -154, -183 and -209) and Dechlorane Plus (DP) were measured and analyzed. Annual arithmetic mean concentrations of ∑12PBDEs (gas+particle phase) and DP (Particle phase) in air samples were 104±95pgm−3 and 3±6pgm−3, respectively. BDE-209 was the dominating congener in all seasons with the contribution of 56±21% of ∑12PBDEs, followed by BDE-28, -47 and -99. The mean fractional abundance of the syn-DP isomer (f syn) in all samples was 0.31±0.14, lower than the value reported for technical DP mixture produced in China (f syn =0.4), indicating depletion of syn-DP in Chinese air. A year monitoring of PBDE in air produced a large dataset that provided a gas-particle partitioning analysis based on a wide temperature range and also individual PBDE congeners. The values of the portion of PBDEs in particle phase to the whole PBDEs in air had a general trend that became higher with the increasing number of bromine atoms at the same temperature and with decreasing temperature for the same congener. The result of PBDEs gas-particle partitioning analysis indicated that PBDEs in gas and particle phases were closer to equilibrium at higher temperature periods. For the first time, the K OA-based absorption model was evaluated for individual PBDE congeners. The results showed that, the model is more suitable for predicting low brominated congeners than high brominated ones, and the accuracy of model predictions decreases along with decrease of temperatures for individual PBDE congeners. [Copyright &y& Elsevier]