Personal and Indoor PM_2.5 Exposure from Burning Solid Fuels in Vented and Unvented Stoves in a Rural Region of China with a High Incidence of Lung Cancer

The combustion of biomass and coal is the dominant source of household air pollution (HAP) in China, and contributes significantly to the total burden of disease in the Chinese population. To characterize HAP exposure related to solid fuel use and ventilation patterns, an exposure assessment study of 163 nonsmoking female heads of households enrolled from 30 villages was conducted in Xuanwei and Fuyuan, two neighboring rural counties with high incidence of lung cancer due to the burning of smoky coal (a bituminous coal, which in health evaluations is usually compared to smokeless coalan anthracite coal available in some parts of the area). Personal and indoor 24-h PM_2.5 samples were collected over two consecutive days in each household, with approximately one-third of measurements retaken in a second season. The overall geometric means (GM) of personal PM_2.5 concentrations in Xuanwei and Fuyuan were 166 [Geometric Standard Deviation (GSD):2.0] and 146 (GSD:1.9) μg/m³, respectively, which were similar to the indoor PM_2.5 air concentrations [GM­(GSD):162 (2.1) and 136 (2.0) μg/m³, respectively]. Personal PM_2.5 was moderately highly correlated with indoor PM_2.5 (Spearman <i>r </i>= 0.70, <i>p</i> < 0.0001). Burning wood or plant materials (tobacco stems, corncobs etc.) resulted in the highest personal PM_2.5 concentrations (GM:289 and 225 μg/m³, respectively), followed by smoky coal, and smokeless coal (GM:148 and 115 μg/m³, respectively). PM_2.5 levels of vented stoves were 34–80% lower than unvented stoves and firepits across fuel types. Mixed effect models indicated that fuel type, ventilation, number of windows, season, and burning time per stove were the main factors related to personal PM_2.5 exposure. Lower PM_2.5 among vented stoves compared with unvented stoves and firepits is of interest as it parallels the observation of reduced risks of malignant and nonmalignant lung diseases in the region

Pre-Pregnancy BMI, Gestational Weight Gain, and the Risk of Hypertensive Disorders of Pregnancy: A Cohort Study in Wuhan, China

<div><p>Background</p><p>Hypertensive disorders of pregnancy (HDP) are major causes of maternal death worldwide and the risk factors are not fully understood. Few studies have investigated the risk factors for HDP among Chinese women. A cohort study involving 84,656 women was conducted to investigate pre-pregnancy BMI, total gestational weight gain (GWG), and GWG during early pregnancy as risk factors for HDP among Chinese women.</p><p>Methods</p><p>The study was conducted between 2011–2013 in Wuhan, China, utilizing data from the Maternal and Children Healthcare Information Tracking System of Wuhan. A total of 84,656 women with a live singleton pregnancy were included. Multiple unconditional logistic regression was conducted to evaluate associations between putative risk factors and HDP.</p><p>Results</p><p>Women who were overweight or obese before pregnancy had an elevated risk of developing HDP (overweight: OR = 2.66, 95% CI = 2.32–3.05; obese: OR = 5.53, 95% CI = 4.28–7.13) compared to their normal weight counterparts. Women with total GWG above the Institute of Medicine (IOM) recommendation had an adjusted OR of 1.72 (95% CI = 1.54–1.93) for HDP compared to women who had GWG within the IOM recommendation. Women with gestational BMI gain >10 kg/m² during pregnancy had an adjusted OR of 3.35 (95% CI = 2.89–3.89) for HDP, compared to women with a gestational BMI gain <5 kg/m². The increased risk of HDP was also observed among women with higher early pregnancy (up to 18 weeks of pregnancy) GWG (>600g/wk: adjusted OR = 1.48, 95% CI = 1.19–1.84).</p><p>Conclusion</p><p>The results from this study show that maternal pre-pregnancy BMI, early GWG, and total GWG are positively associated with the risk of HDP. Weight control efforts before and during pregnancy may help to reduce the risk of HDP.</p></div

Associations of pre-pregnancy BMI, gestational BMI gain, total GWG, and GWG during early pregnancy with risk of HDP^a.

<p>^a. Gestational BMI gain, total GWG, and GWG during early pregnancy were evaluated in separate models.</p><p>^b. Adjusted for age at delivery, education level, parity, offspring sex, and gestational week. Additionally, pre-pregnancy BMI and gestational BMI gain were mutually adjusted. Total GWG also adjusted for pre-pregnancy BMI. (n = 84,656)</p><p>^c. Adjusted for age at delivery, education level, parity, offspring sex, and pre-pregnancy BMI. (n = 63,603)</p><p>Associations of pre-pregnancy BMI, gestational BMI gain, total GWG, and GWG during early pregnancy with risk of HDP<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0136291#t002fn001" target="_blank">^a</a>.</p