Diurnal Variations and Occupational Exposure Risks of Gaseous and Particulate Pollutants in Petrol Filling Stations of Uvwie, Delta State, Nigeria

Petrol filling stations are vital for fuel distribution but act as localised hotspots for gaseous and particulate emissions, posing occupational and environmental health concerns. A cross-sectional observational design was employed to assess air quality and occupational exposure risks in petrol filling stations across 86 stations in Uvwie LGA, Delta State. Selection criteria included daily operational status, accessibility for sampling, and absence of confounding emission sources such as nearby industrial stacks. Morning and afternoon sampling revealed clear shifts: halogen rose by over 600 ppm, combustible gases increased by nearly 200 ppm, and carbon monoxide tripled from morning to afternoon levels, while TVOCs declined by almost 80%, likely due to enhanced atmospheric dispersion. Formaldehyde and oxygen remained stable, and hydrogen sulphide showed episodic but variable patterns. Although most pollutants were below international exposure limits, afternoon peaks in combustible gases and CO highlight elevated occupational risks during hotter, busier hours. These findings emphasise the need for time-sensitive interventions, including morning scheduling of high-emission tasks, vapour recovery systems, improved ventilation, and consistent PPE use to protect attendants and nearby communities.