Assessment of Carbon Monoxide, Nitrogen Dioxide, and Aerosols in Lokoja, Kogi State, North-Central Nigeria (2019–2024)

Air pollution is an escalating environmental and public health concern in rapidly urbanizing cities like Lokoja, Nigeria. This study examines the spatial and temporal variations in carbon monoxide (CO), nitrogen dioxide (NO2), and aerosol concentrations in Lokoja from 2019 to 2024 using Sentinel-5 Precursor (Sentinel-5P) satellite data. Results reveal that though CO levels fluctuated over the years, it showed an increasing trend which peaked in 2024, with the highest concentrations recorded in traffic-dense and industrial areas. NO2 concentrations peaked in 2021 before declining steadily through 2024. Aerosol concentrations remained relatively low from 2019 - 2021 but surged in 2022, followed by a slight decrease in 2023 and stabilization in 2024. A paired sample t-test revealed a significant increase in NO2 levels between 2020 and 2021 (p = 0.003), reflecting higher emissions during post-COVID-19 economic recovery. Similarly, a significant difference in aerosol concentrations was observed between 2021 and 2022 (p = 0.012), aligning with increased industrial and vehicular activity. No significant variations in CO levels were detected across the years. These findings provide critical insights for policymakers and environmental agencies in Nigeria, emphasizing the need for targeted air quality management strategies in mid-sized urban centers like Lokoja.