This paper reported the results of the investigation of vehicular emissions in
selected roads in Abeokuta, Nigeria. Five roads: Olorunsogo, Alabata, Onibode,
Kobape, and Ibara-Orile roads were considered with eight different vehicle types
(Honda, Mazda, Mercedez Benz, Mitsubishi, Nissan, Peugeot, Toyota, and
Volkswagen) on each road. Vehicles were parked 8.0m away from the main road in
downwind direction. The vehicular exhaust emissions monitored were CO2, O2, CO,
and HC emissions. The total mean concentration of measured CO2 emission from
vehicular exhaust on all the roads, ranged between 389100 ppm for Nissan and
465600 ppm for Mitsubishi; O2 emission ranged between 99000 ppm for Toyota and
192000 ppm for Peugeot, also CO emission ranged between 319400 ppm for Peugeot
and 460800 ppm for Nissan while HC emission ranged between 2360 ppm for Toyota
and 4652 ppm for Volkswagen. It could be noted that the air pollutants are high for
most of the vehicles irrespective of the type and higher than both the European and
Nigerian standards. This implies that vehicles are poorly maintained in Nigeria. This
study therefore concluded that vehicular pollution in Abeokuta is significant with
possible serious health and environmental consequences