Background. Reliance on biomass for cooking and heating exposes many women and young children in developing countries to high levels of air pollution indoors. Environmental tobacco smoke also contributes to this indoor air pollution. This study estimates the effects of these sources of air pollution on acute respiratory infections (ARI) in children below 36 months of age in India.

Methods. The analysis is based on 29,768 children age 0–35 months included in India’s 1998–1999 National Family Health Survey (NFHS-2). Logistic regression is used to estimate effects.

Results. In NFHS-2, children living in households using only biomass fuels for cooking or heating are almost twice as likely to have suffered from ARI during the 2 weeks before interview as children in households using cleaner fuels (OR = 1.82; 95% CI: 1.58, 2.09). This effect is somewhat reduced when exposure to environmental tobacco smoke (ETS) and a number of other factors are statistically controlled (OR = 1.58; 95% CI: 1.28, 1.95). With these other variables controlled, children in households using a mix of biomass and cleaner fuels also have a higher risk of ARI than children in households using only cleaner fuels (OR = 1.41; 95% CI: 1.17, 1.70). With controls, the effect of biomass fuel use on ARI is stronger for boys (OR = 1.68; 95% CI: 1.26, 2.23) than for girls (OR = 1.49; 95% CI: 1.11, 2.01). The effect of ETS on ARI is also positive and significant, but smaller when other variables(including type of cooking fuel) are controlled (OR = 1.12; 95% CI: 1.01, 1.23). No modifying effects of cooking smoke and ETS are observed.

Conclusions. Findings support previous research showing positive effects of cooking smoke and ETS on ARI in young children. The relationship needs to be further investigated using more direct measures of smoke exposure and measures of outcome that are more specific to acute lower respiratory infections (ALRI), which are the most important component of overall ARI from a public health standpoint.