Effects of implementing improved cookstoves and heaters to reduce household air pollution: a FRESH AIR study

Introduction: Exposure to household air pollution (HAP) caused by biomass fuel combustion is associated with a wide range of adverse health outcomes. The poorest people living in the rural areas of low- and middle-income countries (LMICs) have limited opportunities to switch to cleaner fuels. Objective: To evaluate effectiveness and acceptability of locally-tailored implementation of an improved cookstoves/heaters program in LMICs. Methods: Interventional implementation study in 649 adults and children living in rural communities in Uganda, Vietnam and Kyrgyzstan, performed after situational analyses and awareness programs. Outcomes included HAP exposure (PM2.5, CO), respiratory symptoms, chest infections, school absence and intervention acceptability. Measurements were conducted at baseline, at 2 months and 6-12 months after intervention. Results: After intervention, health outcomes diminished significantly in Uganda and Kyrgyzstan, and to a smaller extent in Vietnam. PM2.5 levels decreased by 31% to 65%. The figure shows mean PM2.5 with 95% confidence interval; p-value measured between baseline and 6-12 months. CO levels remained below WHO guidelines. Conclusions: Locally-tailored implementation of clean cookstoves/heaters had considerable effects on health outcomes and HAP, yet PM2.5 levels remained above WHO guidelines, especially in Uganda. Villagers indicated high acceptance of the new cookstoves/heaters.