Community effectiveness of stove and health education interventions for reducing exposure to indoor air pollution from solid fuels in four Chinese provinces

Indoor air pollution (IAP) from biomass and coal is a leading cause of mortality and disease burden in the developing world. There is limited evidence of the community effectiveness of interventions for reducing IAP exposure. We conducted a community-based intervention study of stove and health education interventions in four low-income Chinese provinces: Gansu, Guizhou, Inner Mongolia, and Shaanxi. Separate townships in one county in each province were assigned to stove plus behavioral interventions, behavioral interventions alone, and control. Data on household fuel and stove use, and on concentrations of respirable particles (RPM), carbon monoxide (CO), and sulfur dioxide (SO₂), were collected in peak and late heating seasons before and after interventions. The effectiveness of interventions was evaluated using difference-in-difference analysis. Pollutant concentrations were also measured in controlled tests, in which stoves were operated by expert users. In controlled tests, there was consistent and substantial reduction in concentrations of RPM (>88%) and CO (>66%); in the two coal-using provinces, SO₂ concentrations declined more in Shaanxi than in Guizhou. In community implementation, combined stove and behavioral interventions reduced the concentrations of pollutants in rooms where heating was the main purpose of stove use in the peak heating season, with smaller, non-significant, reduction in late heating season. Gansu was the only province where combined stove and behavioral interventions led to pollution reduction where cooking was the primary purpose of stove use. Compared to the control group, no significant IAP reductions were seen in groups with health education alone.