Inhalation exposure to fine particles and particle size distributions among rural Chinese

摘要

Air pollution is one leading environmental risk factor in China causing millions of premature deaths every year. It has been documented that adverse health impacts of particulate matter are not solely associated with the mass but factors like particle size and toxic chemical components. In rural China, severe indoor as well as ambient air pollution has been identified due to high dependence on traditional solid fuels including coals and biomass fuels in daily lives particularly for space heating. In this study multiple-site field measurements have been carried to investigate daily inhalation exposure to particles in rural China, by using personal carried samplers. Results showed that daily inhalation exposure to fine PM2.5 varied in nearly two orders of magnitude ranging from 10 to over 1200 u.g/m3. The overall median and geometric means were around 130 ug/m3 that was several times of WHO guidelines for indoor air quality. Primarily fuels are one main cause causing seasonal difference, as well as variations among rural residents. The study also evaluated size distributions and presence of submicron particles in inhaled particles, which found similar size distributions among the residents using clean and polluting fuels, but significant differences between winter and summer periods. Results from this study fill in important data gaps in inhalation exposure among rural Chinese, and provided strong supports for clean intervention and risk assessment on air pollution in rural China and controls on traditional solid fuel use.