Environmental Determinants of Childhood Asthma in Petrochemical Corridor Communities of Akwa Ibom State: A Prospective Cohort Study

Childhood asthma attributable to environmental pollutant exposure in Nigeria's petrochemical corridors represents a significant and poorly characterised public health burden, particularly in communities surrounding refineries and petrochemical facilities in Akwa Ibom State. This study investigates the environmental determinants of childhood asthma incidence in petrochemical corridor communities of Akwa Ibom through a prospective birth cohort design, following 900 newborns from birth to age five in exposed communities compared to 450 in unexposed control communities in the same state. Environmental exposure assessment includes quarterly air quality monitoring for particulate matter (PM2.5 and PM10), nitrogen dioxide, benzene, and volatile organic compounds at residential locations using portable monitors and passive samplers. Asthma incidence is determined through annual paediatric respiratory assessments using spirometry, skin prick testing, and the International Study of Asthma and Allergies in Childhood validated diagnostic criteria. Soil and tap water samples at study sites are additionally analysed for heavy metal contamination. Distributed lag non-linear models in R are used to estimate exposure-lag-response relationships between pollutant concentrations and asthma risk, controlling for genetic susceptibility, indoor allergen burden, and socioeconomic factors. The Environmental Epigenome Framework and the Developmental Origins of Health and Disease theory provide the conceptual basis. Original contributions include the first prospective environmental exposure and childhood asthma cohort study in Nigeria's oil corridor. Findings will support the National Environmental Standards and Regulations Enforcement Agency in setting enforceable ambient air quality standards. Keywords: childhood asthma, environmental pollutants, petrochemical corridor, prospective cohort, Akwa Ibom State.