Toxicity potential of automobile carbon monoxide emission along a majour highway in Sango-Ota, Ogun State, Nigeria

This study investigated the toxicity potential of carbon monoxide along a major highway in Sango-Ota, an emerging city, in Nigeria. Ambient air carbon monoxide was monitored and measured at ten different locations using the GM8805 benetech carbon monoxide monitor. Coca-Cola junction was selected as the control location for this study. The 1-hr averaging period measured for carbon monoxide concentrations within the selected locations ranged between 25.2 ppm and 29.3 ppm while at the control point, it was measured to be 8 ppm. The extrapolated 8-hr averaging period for carbon monoxide concentration ranged between 14.076 ppm and 16.366 ppm with the concentration at the control point being at 4.4688 ppm. The extrapolated 24-hr averaging period for carbon monoxide concentration ranged between 10.357 ppm and 12.042 ppm with the concentration at the control point being 3.288 ppm. An assessment of toxicity potential of these locations based on Federal Environmental Protection Agency (FEPA), United States Environmental Protection Agency (USEPA) and World Health Organization (WHO) statutory limits were all above unity (one) except at the control location and this poses as a threat to human lives. These values showed unhealthy air conditions at these regions of the emerging city. This study establishes that traffic congestions contribute significantly to the ambient air thereby reducing its quality thus calls for the attention of regulatory bodies to rise to protection of commuters and businessmen along the major highways in emerging cities in Nigeria.