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Air samples were concurrently collected using high volume air samplers for 24 h every week from September 2008 to August 2009 at 15 sites (11 urban, 1 suburban, and 3 background/rural) across China. Twelve polybrominated diphenyl ether (PBDE) congeners (BDE-17, -28, -47, -66, -85, -99, -100, -138, -153, -154, -183, and -209) were measured. Total PBDE concentrations (Σ12PBDEs) in air (gas + particle phases) were in the range of 11.0-838 pg m-3 with a mean of 232 ± 72 (mean ± SE) pg m-3. The site with the highest concentration was Guangzhou (838 ± 126 pg m-3), followed by Beijing (781 ± 107 pg m-3). Significant positive correlations were found between PBDEs levels and urban population (R = 0.69, P < 0.05) and gross industrial output values (R = 0.87, P < 0.001) as well. BDE-209 was the dominating congener with the contribution of 64 ± 23% to Σ12PBDEs, followed by BDE-47(8 ± 8%) and -99(6 ± 5%) at all urban and suburban sites. At background/rural sites, however, BDE-47 was the dominating congener, followed by BDE-99, together accounting for 52 ± 21% of Σ12PBDEs, while BDE-209 was only 11 ± 2%. It was found that PBDEs at the 15 sites showed a primary distribution and fractionation pattern. This study produced more than 700 pairs of air samples in gaseous and particulate phases with a wide temperature range of ∼60 °C, providing a good opportunity to investigate gas–particle partitioning for individual PBDE congeners. The results of gas–particle partitioning analysis for PBDEs using both subcooled-liquid–vapor pressure (PL)-based and octanol-air partition coefficient (KOA)-based models indicated that PBDEs in air at all sampling sites had not reached equilibrium because the slope values (mO) in the KOA-based equation and the opposite slope values (mP) in the PL-based equation at all 15 sampling sites were less than 1. It also found that both mO and –mP were significantly and positively correlated with the annual average temperatures of sampling sites and also significantly and negatively correlated with the mole masses of PBDE congeners, indicating a general trend that the higher the temperature at the sampling site and the lower the mole mass of the PBDE congeners are, the closer to the equilibrium the congeners approach and vice versa. To our knowledge, this is the first study to report the correlations of the slope values for both the KOA-based and PL-based equations with temperatures at sampling sites and mole masses for individual PBDE congeners. [ABSTRACT FROM AUTHOR]

The article discusses a study which concluded that the Simplified Chinese versions of questionnaires on back pain beliefs are valid and reliable research tools to be used among the Chinese medical professionals in mainland China. Based on a psychometric evaluation, the Back Beliefs Questionnaire (BBQ), Health Care Providers' Pain and Impairment Relationship Scale (HC-PAIRS) and the Fear-Avoidance Beliefs Questionnaire (FABQ) were found to have internal consistency and construct validity.

This paper presents the first comprehensive survey of 19 novel brominated flame retardants (NBFRs) in soil samples collected among five Asian countries. High variability in concentrations of all NBFRs was found in soils with the geometric mean (GM) values ranging from 0.50 ng/g dry weight (dw) in Vietnam to 540 ng/g dw in the vicinity of a BFR manufacturer in China. In urban, rural, and background locations, the GM concentrations of Σ19NBFRs decreased in the order of Japan > South Korea > China > India > Vietnam. Correlations among different NBFR compounds were positive and statistically significant (p < 0.05), suggesting that they originate from similar sources. Evidence for simultaneous application between polybrominated diphenyl ethers (PBDEs) and NBFRs were also noted. Principal component analysis of NBFR concentrations revealed specific pollution sources for different NBFRs coming from urban, BFR-related industrial, and e-waste sites. For the first time, this study demonstrates a "point source fractionation effect" for NBFRs and PBDEs. The concentrations of all NBFRs and PBDEs were negatively and significantly correlated with the distance from BFR-related industrial and e-waste regions. Positive and significant correlation between population density and NBFR concentrations in soils was identified. Our study revealed that the primary sources effects were stronger than the secondary sources effects in controlling the levels and distribution of NBFRs and PBDEs in soils in these five Asian countries. [ABSTRACT FROM AUTHOR]