Indoor concentrations of nitrogen dioxide and sulfur dioxide from burning solid fuels for cooking and heating in Yunnan Province, China.

The Chinese national pollution census has indicated that the domestic burning of solid fuels is an important contributor to nitrogen dioxide (NO2 ) and sulfur dioxide (SO2 ) emissions in China. To characterize indoor NO2 and SO2 air concentrations in relation to solid fuel use and stove ventilation in the rural counties of Xuanwei and Fuyuan, in Yunnan Province, China, which have among the highest lung cancer rates in the nation, a total of 163 participants in 30 selected villages were enrolled. Indoor 24-h NO2 and SO2 samples were collected in each household over two consecutive days. Compared to smoky coal, smokeless coal use was associated with higher NO2 concentrations [geometric mean (GM) = 132 µg/m(3) for smokeless coal and 111 µg/m(3) for smoky coal, P = 0.065] and SO2 [limit of detection = 24 µg/m(3) ; percentage detected (%Detect) = 86% for smokeless coal and 40% for smoky coal, P < 0.001]. Among smoky coal users, significant variation of NO2 and SO2 air concentrations was observed across different stove designs and smoky coal sources in both counties. Model construction indicated that the measurements of both pollutants were influenced by stove design. This exposure assessment study has identified high levels of NO2 and SO2 as a result of burning solid fuels for cooking and heating.

Muscle-building supplement use and increased risk of testicular germ cell cancer in men from Connecticut and Massachusetts.

BACKGROUND: No analytic epidemiological study has examined the relationship between use of muscle-building supplements (MBSs) and testicular germ cell cancer (TGCC) risk. METHODS: We conducted a population-based case-control study including 356 TGCC cases and 513 controls from Connecticut and Massachusetts. RESULTS: The odds ratio (OR) for ever use of MBSs in relation to risk of TGCC was significantly elevated (OR=1.65, 95% confidence interval (CI): 1.11-2.46). The associations were significantly stronger among early users, men with more types of MBSs used, and longer periods of use. CONCLUSIONS: MBS use is a potentially modifiable risk factor that may be associated with TGCC.