Selected heavy metals in blood of male Nigerian smokers

Lead, cadmium and zinc levels were determined in the blood of 47 all male smokers (age range, 19-56 years). The subjects were classified into 4 subgroups based on the number of years of smoking, namely: 1-5, 6-10, 11-15 years, >16 years. Thirty all male non-smokers serves as the control. The weight, height and body mass indexes of all subjects were noted in addition to other information obtained through structured questionnaire. Those that were likely to be exposed to any of these metals either occupationally or through other life style habits were excluded from the study. The mean values of blood lead (BPb), blood cadmium (BCd) and blood zinc (BZn) in male smokers (n=47) were 43.26 +/- 4.28, 98.21 +/- 6.39 and 104.84 +/- 3.66 microg dL(-1), respectively while the corresponding mean values for these parameters in the non smokers (n = 30) were 32.44 +/- 3.02, 76.51 +/- 4.59 and 90.38 +/- 2.55 microg dL(-1), respectively. The smokers have statistically significant higher BPb, BCd and BZn than the non-smokers (p < 0.001, p < 0.001 and p < 0.001, respectively). The results appear to confirm the presence of these metals as component of cigarette and agree with similar findings from literature. Consequently, it is probable that high level of these metals in blood of smokers is from tobacco smoking. Additionally it appears that the number of years of smoking has nothing to do with the level of these metals in smokers' blood.