Project Summary In low- and middle-income countries ~2.8 billion people are exposed daily to smoke from cooking fires, termed household air pollution (HAP), resulting in an estimated 2.3M deaths and 91.4M DALYs in 2019. A large proportion of HAP-attributable deaths and DALYs are due to respiratory disease. Establishment of ideal lung health in childhood is critical to reduce risk for future respiratory disease. We hypothesize that prenatal to age 1 exposure to HAP impairs lung health and programs future disease risk. We further hypothesize that higher mucin gene expression in response to HAP exposure is a key biological mechanism, and that genotypes that exhibit a stronger mucin response to HAP are more susceptible to HAP exposure. We propose to build on an existing pregnancy cohort in Ghana – the Ghana Randomized Air Pollution and Health Study, or GRAPHS – to assess how prenatal to age one HAP exposure affects lung health through age 13 years. We will use well- established, validated methods to assess these outcomes. In the long run, our research will help build the evidence base for cost effective interventions to improve health by reducing HAP exposure.