Assessment of airborne particulate pollution and health risks in communities surrounding Obajana cement factory, Nigeria

Abstract

Industrial air pollution remains one of the most pressing environmental and public health issues, particularly in developing nations where rapid industrial growth often surpasses regulatory capacity. This study assessed the potential non-carcinogenic and carcinogenic health risks associated with exposure to fine and coarse particulate matter (PM₂.₅ and PM₁₀) in communities surrounding the Dangote Cement Manufacturing Plant, Obajana, Kogi State, Nigeria. Air quality sampling was conducted using standard gravimetric methods, and results were analyzed against World Health Organization (WHO) and United States Environmental Protection Agency (USEPA) air quality benchmarks. Health Risk Models—Average Daily Dose (ADD), Hazard Quotient (HQ), and Excess Lifetime Cancer Risk (ELCR)—were applied to estimate exposure impacts for adults and children. Results showed that PM₂.₅ concentrations ranged from 41.2 µg/m³ to 291.6 µg/m³, while PM₁₀ concentrations ranged between 45.4 µg/m³ and 230.1 µg/m³. Most HQ values exceeded unity (HQ > 1), indicating potential non-carcinogenic effects, and ELCR values were above the acceptable threshold of 1 × 10⁻⁶, and suggesting possible carcinogenic risk. Communities within 0.5–2 km of the plant recorded the highest pollutant loads reaching up to 0.0023 (ELCR ≥ 1×10⁻³), underscoring the influence of proximity. Overall, the study revealed that residents of Obajana and neighboring settlements are chronically exposed to unsafe particulate concentrations, posing significant long-term health implications.