Investigation into the Ambient Concentrations of Carbon Monoxide in Nsukka Urban, South East , Nigeria, and its likely effects on Human Health

Abstract

Carbon monoxide (CO) is a major air pollutant that causes environmental and health concerns.  Measurements of ambient CO concentrations were made in Nsukka Urban, to determine its concencentration level in line  with the World Health Organisation (WHO)’s guideline for an 8-hour period and to determine the extent in the increase in CO composition in ambient air given that a similar investigation was conducted about 7 years ago. CO levels were monitored for about 8 hours daily at four sampling points in Nsukka Urban. It was measured at different times using gas monitors. The highest single recorded value was 74 ppm at the Post office area in an afternoon, while the least value was recorded at the University of Nigeria, Nsukka (UNN) First (1st) gate.The mean values for each  8 hr period  ranged from 1 ppm to 10 ppm, depending on the time and the location of measurements. Comparing the results of this study with that conducted in 2011 showed that the 2011 CO concentrations were higher than the concentrations recorded in 2018. This may be due to meterological factors, emission sources, and the use of different CO detectors. An exception to this was the results obtained at the Park area, the values were below the WHO maximum limit of 9 ppm for an 8-hourly average time that could cause health problems. In addition to this, the fact that CO is a precussor for CO2 and ground level O3, which are the most prominent greenhouse gases, the values may contribute to global warming and consequent environmental hazards, hence emission inventories are needed for proper comparison of sources of the CO and levels emitted to help in pollutant monitoring and control.Key words: ambient concentrations, carbon monoxide, human health, climate