Impacts of firewood burning for cooking on respiratory health and healthcare utilisation: Empirical evidence from Sri Lankan micro-data.

Despite escalating income levels of Sri Lankan households, 70.3% of them still depend on firewood for cooking. This might lead to bad respiratory health and thereby, increased healthcare utilisation. With this backdrop, this paper examines how firewood burning for cooking influences respiratory health and healthcare utilisation of Sri Lankans. The study proposes a theoretical model to explain effects of firewood burning on respiratory health and healthcare utilisation and empirically tests it using nation-wide micro-data of 79,170 individuals belonging to 21,748 households. The data are drawn from the most recent wave of Sri Lankan household income and expenditure survey. After addressing potential endogeneity by applying instrumental variable regression models, the study finds that firewood burning increases households' probability of asthma prevalence by 10.9 percentage points (P < 0.001), out-patient care utilisation by 33.1 percentage points (P < 0.001), and in-patient care utilisation by 17.5 percentage points (P < 0.001), on average. Our individual level analysis demonstrates that females are more vulnerable to bad respiratory health induced by firewood burning (β = 0.055, P < 0.001) compared to males (β = 0.008, P > 0.1). The results imply policies on promoting improved-cooking stoves, separated-kitchen designs, and switching more towards cleaner energy sources, including LP gas and solar power.