Polluting characteristics, sources, cancer risk, and cellular toxicity of PAHs bound in atmospheric particulates sampled from an economic transformation demonstration area of Dongguan in the Pearl River Delta, China.

The Songshan Lake Science and Technology Industrial Park is a national economic transition demonstration area, which centers at a traditional industrial region, in Dongguan, China. We were interested in the involved atmospheric particulates-bound PAHs regarding their sources, cancer risk, and related cellular toxicity for those in other areas under comparable conditions. In this study, the daily concentrations of TSP, PM10, and PM2.5 were averaged 127.95, 95.91, and 67.62 µg/m3, and the bound PAHs were averaged 1.31, 1.22, and 0.77 ng/m3 in summer and 12.72, 20.51 and 40.27 ng/m3 in winter, respectively. The dominant PAHs were those with 5-6 rings, and 4-6 rings in summer and winter, respectively. The incremental lifetime cancer risk (ILCR) (90th percentile probability) of total PAHs was above 1.00E-06 in each age group, particularly high in adolescents. Sensitivity analysis indicated that slope factor and body weight had greater impact than exposure duration and inhalation rate on the ILCR. Moreover, treatment of human bronchial epithelial BEAS-2B cells with mixed five indicative PAHs increased the formation of ROS, DNA damage (elevation in γ-H2AX), and protein levels of CAR, PXR, CYP1A1, 1A2, 1B1, while reduced the AhR protein, with the winter mixture more potent than summer. For the sources of PAHs, the stable carbon isotope ratio analysis and diagnostic ratios consistently pointed to petroleum and fossil fuel combustion as major sources. In conclusion, our findings suggest that particulates-bound PAHs deserve serious concerns for a cancer risk in such environment, and the development of new power sources for reducing fossil fuel combustion is highly encouraged.

Societal costs of rheumatoid arthritis in China: a hospital-based cross-sectional study.

OBJECTIVE: To estimate the annual direct and indirect costs of rheumatoid arthritis (RA) in China and identify the predictors for cost of illness. METHODS: A cross-sectional study of cost of illness from the societal perspective was conducted on 829 patients with RA in 21 tertiary care hospitals in China between July 2009 and December 2010. Data on demographics, clinical variables, and components of costs were collected by physician interview. Costs were represented in 2009 US dollars using purchasing power parity estimates. Univariate and multivariate linear regression analyses were performed to identify the predictors for cost of illness. RESULTS: The mean ± SD total cost of RA in China was $3,826 ± $5,659 per patient-year, given a gross domestic product per capita of $6,798 in China in 2009. Direct costs and indirect costs comprised 90.0% and 10.0% of the total costs, respectively. Drug expense represented approximately half of the total costs, dominated by biologic agents (48.2%) and disease-modifying antirheumatic drugs (23.5%). Additionally, the cost of extracted herbal drugs and traditional Chinese medicine comprised ∼17.6% of the drug expense. Higher education level, noninsured status, longer disease duration, more extraarticular manifestations, and higher Health Assessment Questionnaire score independently predicted higher total costs. CONCLUSION: Our results provide the first study of costs of RA in China. This study not only demonstrates the economic burden of RA, but also identifies the predictors that could be interventional factors to reduce the societal costs of RA in China.