Author(s): Abdul Raheem AMO, Owolabi AA and Abdulrahim HA

Abstract: This research evaluated in-vehicle and ambient air samples for three pollutants; NO₂, SO₂, CO and deduced the air quality index, emission factors and health risk assessments from the pollutants concentrations. The concentrations of these pollutants were measured in-vehicle using two modes of transportation with open-window scenario while ambient measurements covered three hours of the day at six sampling points covering two states along the highway. NO₂, SO₂ and CO concentrations were measured with Altair-5X MGD. Vehicular volume was conducted per 45 minutes and self-administered forms were used to draw health data on the samples. The values of the in-vehicle exposure in μgm-3 ranges from 90–1270 NO₂; 124-810 SO₂ and 3262-23800 CO. The highest average in-vehicle exposure appeared in cars with the following μgm-3 average NO₂, 426±109; SO₂ 571±61 and CO 10433±1650. The Ambient air pollutants results showed that the mean concentrations of NO₂ and SO₂ exceeded the 1-hour averaging time-limit of 40 μgm^-3 set by FEPA but within the 1-hour averaging time-limit set by EPA while the mean concentration of CO falls within minimal limit stipulated by WHO. Air Quality Index was deduced with rating for NO₂ and SO₂ which ranged from good “A” through unhealthy for sensitive group “UHFS’ to hazardous “F” and rating for CO, F across the sampling points. The study established strong evidence that traffic volume affects the quality of air in the atmosphere at all sampling points. Results from questionnaire indicated some key health risks related with contact to pollutants by commuters and other road users.

DOI: 10.33545/26174693.2019.v3.i1a.106