Evaluation of Blood Levels of Carbon Monoxide in Smokers in Nnewi Metropolis

Cigarette smoking is a major source of exposure to carbon monoxide (CO). CO is a colourless, odourless gas that displaces oxygen in the blood, which can lead to a variety of health problems, including heart disease, stroke, peripheral vascular disease, cancer, reduced cognitive function, premature birth, and low birth weight. This study was conducted to evaluate the levels of Carbon monoxide (CO) in active smokers in Nnewi Metropolis. This was a cross-sectional study involving 100 participants comprising of 50 smokers and 50 non-smokers, all within the age range of 18-45 years. The participants were recruited by simple random sampling technique. Recruited smokers were grouped based on duration of smoking into those who had smoked for less than 2 years (n = 20), those who had smoked for 2 years to 5 years (n = 19) and those who had smoked for more than 5 years (n = 11). The participants were also grouped based on type of substance smoked into those who smoke cigarette (n-12) alone, those who smoked weed alone (n=20) and those who smoked other substances aside from cigarette and weed (n=18). Carbon monoxide levels was determined by spectrophotometric measurement of caboxyhaemoglobin as it has been validated various researches as valuable for measurement of exposure to carbon monoxide. Independent sample test and Analysis of variance (ANOVA) were used for statistical analysis of data. The mean ± SD carboxyhaemoglobin level (4.45 ± 0.86 %) smokers was significantly higher than in non-smokers (carboxyhaemoglobin 1.61 ± 0.21 %, p<0.001). There were no differences in mean levels of carboxyhaemoglobin between individuals who smoke cigarette compared to individuals who smoke weed (p>0.05), individuals who smoked cigarette compared to individuals who smoke other substances (p>0.05) and individuals who smoked weed compared to individuals who smoke other substances (p>0.05). Carboxyhaemoglobin was higher in individuals who have been smoking for more two years and above than in individuals who have been smoking for two years and above (p>0.05). This study observed that carbon monoxide level was higher in active smokers than in non-smokers. This study also observed that carbon monoxide was not dependent on the type of substance smoked. However, duration smoking for less than 2years was characterised by lower COHB% compared with duration of more than 2 years smoking. Although the levels of caaboxyhaemoglobin observed in smoker was below WHO approved permissible level of carbon monoxide in active smokers, the outcome of this study further buttresses the fact that smoking predisposes individuals to carbon monoxide toxicity.