HEALTH RISK ASSESSMENT OF DUST-BOUND HEAVY METALS IN URBAN ROADSIDE ENVIRONMENTS IN KOGI STATE, NIGERIA

Abstract

Natural processes and anthropogenic activities contribute heavily to the roadside as a major sink for toxic heavy metals, with health implications for residents. A study was conducted to determine the concentrations and health impacts of heavy metals bound to roadside dust at selected sites within the urban road system in Kogi State, Nigeria. Roadside dust was randomly collected at Nataco, Ganaja, Ejule and Okene and analyzed by ICP-OES for Pb, Cd, Cr, As, Ni and Zn. Zn ranged from 81.029–168.000 mg/kg; Pb ranged from 11.01–28.14 mg/kg. Nataco had the highest Pb (28.14), Cd (1.003), and As (0.911). CF showed values ranging from considerable to very high for Cd (up to 5.02) and As (up to 6.18). Igeo indicated moderate pollution for Cd (+1.74) and As (+2.04). Hazard values were all <1 (ranging from 0.008 to 0.144). Cancer risks (1.44×10⁻⁶ to 6.63×10⁻⁶) were below the USEPA limit (1×10⁻⁶). PCA identified traffic-industrial-combustion (58.2%) and tire wear (21.4%). The roadside dust in the urban centers of Kogi State shows higher concentrations of heavy metals at Nataco and Ganaja Junction. The risk currently posed to the lives of the urban center's dwellers has been reported to be acceptable for now. However, regular surveillance and efforts toward pollution prevention/control are encouraged to reduce future buildup and protect susceptible individuals.