Effect of stove intervention on household air pollution and the respiratory health of women and children in rural Nigeria

Domestic cooking with biomass fuels exposes women and children to pollutants that impair health. The objective of the study was to investigate the extent of household air pollution from biomass fuels and the effectiveness of stove intervention to improve indoor air quality, exposure-related health problems, and lung function. We conducted a community-based pilot study in three rural communities in southwest Nigeria. Indoor levels of particulate matter (PM2.5) and carbon monoxide (CO) were measured, and exposure-related health complaints were assessed in 59 households that used firewood exclusively for cooking. Fifty-nine mother-child pairs from these households were evaluated pre-intervention and 1 year after distribution and monitored use of low-emission stoves. Mean age (+/- SD; years) of mothers and children were 43.0 +/- 11.7 and 13.0 +/- 2.5, respectively. Median indoor PM2.5 level was 1414.4 mu g/m(3) [interquartile range (IQR) 831.2-3437.0] pre-intervention and was significantly reduced to 130.3 mu g/m(3) (IQR 49.6-277.1; p < 0.0001) post-intervention. Similarly, the median CO level was reduced from 170.3 ppm (IQR 116.3-236.2) to 14.0 ppm (IQR 7.0-21.0; p < 0.0001). There were also significant reductions in frequency of respiratory symptoms (dry cough, chest tightness, difficult breathing, and runny nose) in mothers and children. Over 25 % of mothers and children had moderate airway obstruction on spirometry pre-intervention that did not improve 1 year after intervention period. Cooking with firewood causes household air pollution and compromised lung health. Introduction of low-emission stoves was effective at improving indoor air quality and reducing exposure-related symptoms.