Volatile Organic Compounds from Gas Flaring and Their Atmospheric Implications in the Niger Delta

Abstract

This study investigates volatile organic compounds (VOCs) emitted from gas flaring in the Niger Delta, focusing on their atmospheric lifetimes and transformation pathways under tropical conditions. Field measurements combined with photochemical modelling (MCM v3.3.1 coupled with AERMOD) revealed accelerated degradation of BTEX compounds, with lifetimes shortened to 2–12 hours compared with 6–18 hours in temperate regions. Elevated solar radiation and hydroxyl radical concentrations were identified as the main drivers of rapid secondary pollutant formation. Secondary organic aerosols (SOAs) reached nearly double the World Health Organization (WHO) guideline, while ground-level ozone exceeded recommended thresholds. From a public health perspective, benzene concentrations were nearly nine times above WHO limits, formaldehyde exceeded guidelines threefold, and ozone accumulation was linked to heightened risks of respiratory, cardiovascular, and carcinogenic outcomes in nearby communities. These findings highlight the unique role of tropical photochemistry in amplifying health and climate risks from flaring emissions, demonstrating that oil-producing communities in the Niger Delta face pollution burdens comparable to those in heavily industrialised cities.