Patterns and predictors of personal exposure to indoor air pollution from biomass combustion among women and children in rural China.

UNLABELLED: Indoor air pollution (IAP) from domestic biomass combustion is an important health risk factor, yet direct measurements of personal IAP exposure are scarce. We measured 24-h integrated gravimetric exposure to particles < 2.5 μm in aerodynamic diameter (particulate matter, PM₂.₅) in 280 adult women and 240 children in rural Yunnan, China. We also measured indoor PM₂.₅ concentrations in a random sample of 44 kitchens. The geometric mean winter PM₂.₅ exposure among adult women was twice that of summer exposure [117 μg/m³ (95% CI: 107, 128) vs. 55 μg/m³ (95% CI: 49, 62)]. Children's geometric mean exposure in summer was 53 μg/m³ (95% CI: 46, 61). Indoor PM₂.₅ concentrations were moderately correlated with women's personal exposure (r=0.58), but not for children. Ventilation during cooking, cookstove maintenance, and kitchen structure were significant predictors of personal PM₂.₅ exposure among women primarily cooking with biomass. These findings can be used to develop exposure assessment models for future epidemiologic research and inform interventions and policies aimed at reducing IAP exposure. PRACTICAL IMPLICATIONS: Our results suggest that reducing overall PM pollution exposure in this population may be best achieved by reducing winter exposure. Behavioral interventions such as increasing ventilation during cooking or encouraging stove cleaning and maintenance may help achieve these reductions.