ASSESSMENT OF AIR QUALITY INDEX AND ITS HEALTH IMPLICATION IN APAPA SEAPORTS LAGOS

This study assessed air quality and estimated the potential health implications of selected gaseous pollutants in Apapa and Tin Can Island Seaports, Lagos State, Nigeria. Air quality measurements were obtained using a calibrated Testo 350 flue gas analyser at selected monitoring locations within the two seaports. Concentrations of carbon monoxide (CO), nitrogen dioxide (NO₂), sulfur dioxide (SO₂), carbon dioxide (CO₂), and hydrocarbons (HC) were measured and analysed using descriptive statistics. NO₂ and SO₂ concentrations were converted from parts per million (ppm) to micrograms per cubic metre (µg/m³) and compared with the 2021 World Health Organization (WHO) Air Quality Guidelines. Potential health implications were further assessed using concentration-response relationships and attributable fractions (AFs). The results showed mean CO concentrations of 26.15 ppm in Apapa and 25.74 ppm in Tin Can Island. The corresponding mean concentrations of NO₂ were 60.18 µg/m³ and 58.27 µg/m³, while SO₂ concentrations were 86.46 µg/m³ and 83.77 µg/m³, respectively. These measured concentrations were above the relevant WHO guideline values; however, the comparisons should be interpreted in relation to the different averaging periods specified by the WHO guidelines. The estimated attributable fractions for NO₂ were 16.30% for Apapa and 15.84% for Tin Can Island, while those for SO₂ were 4.96% and 4.81%, respectively. Under the concentration-response assumptions adopted in this study, NO₂ produced a higher model-based attributable fraction than SO₂. The findings indicate that port-related combustion activities, including vessel operations, heavy-duty vehicle movements, cargo-handling activities, and other fuel-consuming operations, contribute to gaseous air pollution in the study areas.The study recommends strengthened air-quality monitoring, improved emission controls for ships and port vehicles.