Sosanya Peter & Remi-esan Ifelolu

Polycyclic Aromatic Hydrocarbons (PAHs) are persistent toxic substance and omnipresent environmental contaminants causing toxic health effects to human and potential threats to the environment. This study determines the concentration and health risk of polycyclic aromatic hydrocarbons (PAHs) in industrial road. Ten samples were collected during the dry season from Sango Otta Ogun State in Southwest Nigeria. Dust particles that accumulated on surfaces of pavements and roadside within a 5m radius circle were collected and analyzed using standard method. Gas chromatography-mass spectrometry (GC-MS) were used to determine the twenty-four potential toxic congeners according to USEPA PAHs standard. The average concentration of PAHs in the dust samples were 1.80 mgkg-1 , with concentrations ranging from 23.31 mgkg-1 to 1.74 mgkg-1. The PAH level in Rubee Medical Road were the greatest, with 3-Methylcholanthracene being the highest PAH congener 10.47 mgkg-1, while the PAH level in Conoil Bus stop were the lowest (1.74 mgkg-1). Potential human health risk of the exposure to PAHs by inhalation and skin contact were evaluated using the Chronic Daily Intake (CDI), which ranged from 9.59×10-18 mgkg -1day -1 to 1.09 ×10 -8 mgkg -1day -1 , Hazard Quotient (HQ). Hazard Index (HI) and Cancer Risk (CR) of all PAH congeners has the highest HQ value. The PAHs' CR values were greater than the USEPA's allowed limit of 0.2 mg/m3 , indicating that they may be carcinogenic. This data reveals that the inhalation route is primarily responsible for the total carcinogenic risk of PAHs to humans. Keywords: Polycyclic aromatic hydrocarbons, hazard quotient, cancer risk, health risk, urban 0150