Seasonal variation in outdoor, indoor, and personal air pollution exposures of women using wood stoves in the Tibetan Plateau: Baseline assessment for an energy intervention study.
Cooking and heating with coal and biomass is the main source of household air pollution in China and a leading contributor to disease burden. As part of a baseline assessment for a household energy intervention program, we enrolled 205 adult women cooking with biomass fuels in Sichuan, China and measured their 48-h personal exposure to fine particulate matter (PM2.5) and carbon monoxide (CO) in winter and summer. We also measured the indoor 48-h PM2.5 concentrations in their homes and conducted outdoor PM2.5 measurements during 101 (74) days in summer (winter). Indoor concentrations of CO and nitrogen oxides (NO, NO2) were measured over 48-h in a subset of ~80 homes. Women's geometric mean 48-h exposure to PM2.5 was 80μg/m(3) (95% CI: 74, 87) in summer and twice as high in winter (169μg/m(3) (95% CI: 150, 190), with similar seasonal trends for indoor PM2.5 concentrations (winter: 252μg/m(3); 95% CI: 215, 295; summer: 101μg/m(3); 95% CI: 91, 112). We found a moderately strong relationship between indoor PM2.5 and CO (r=0.60, 95% CI: 0.46, 0.72), and a weak correlation between personal PM2.5 and CO (r=0.41, 95% CI: -0.02, 0.71). NO2/NO ratios were higher in summer (range: 0.01 to 0.68) than in winter (range: 0 to 0.11), suggesting outdoor formation of NO2 via reaction of NO with ozone is a more important source of NO2 than biomass combustion indoors. The predictors of women's personal exposure to PM2.5 differed by season. In winter, our results show that primary heating with a low-polluting fuel (i.e., electric stove or wood-charcoal) and more frequent kitchen ventilation could reduce personal PM2.5 exposures. In summer, primary use of a gaseous fuel or electricity for cooking and reducing exposure to outdoor PM2.5 would likely have the greatest impacts on personal PM2.5 exposure.
Department of Building Science, Tsinghua University, Beijing, China.
Kun
K
Ni
Institute on the Environment, University of Minnesota, St. Paul, MN, USA.
Ellison
E
Carter
Environmental Chemistry and Technology Program, University of Wisconsin, Madison, WI, USA; Department of Civil and Environmental Engineering, University of Wisconsin, Madison, WI, USA.
James J
JJ
Schauer
MRC-PHE Center for Environment and Health, Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, UK.
Majid
M
Ezzati
College of Resources and Environment, University of the Chinese Academy of Sciences, Beijing, China.
Yuanxun
Y
Zhang
Department of Building Science, Tsinghua University, Beijing, China.
Hongjiang
H
Niu
Department of Civil and Environmental Engineering, University of Wisconsin, Madison, WI, USA.
Alexandra M
AM
Lai
Department of Building Science, Tsinghua University, Beijing, China.
Ming
M
Shan
College of Resources and Environment, University of the Chinese Academy of Sciences, Beijing, China.
Yuqin
Y
Wang
Department of Building Science, Tsinghua University, Beijing, China. Electronic address: xyang@tsinghua.edu.cn.
Xudong
X
Yang
Institute on the Environment, University of Minnesota, St. Paul, MN, USA; Institute for Health and Social Policy, Department of Epidemiology, Biostatistics & Occupational Health, McGill University, Montréal, QC, Canada. Electronic address: jill.baumgartner@mcgill.ca.
Jill
J
Baumgartner
D000328:Adult; D000397:Air Pollution / Q000032:analysis*; D002248:Carbon Monoxide / Q000032:analysis; D003296:Cooking; D004781:Environmental Exposure / Q000032:analysis* / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D009589:Nitrogen Oxides / Q000032:analysis; D012621:Seasons; D018609:Tibet / Q000453:epidemiology; D014934:Wood
D009589:Nitrogen Oxides; D002248:Carbon Monoxide
Carbon monoxide; China; Energy; Exposure; Household air pollution; Nitrogen oxides; Particulate matter; Tibetan Plateau