BACKGROUND: Smoking is the source of exposure to various hazardous substances including nicotine, tar, carbon monoxide and heavy metals. Lead (Pb), mercury (Hg) and cadmium (Cd) contained in the cigarette smoke are among the top 10 chemicals harmful to health. In this connection, this study investigated the effects of smoking on concentrations of blood heavy metals and clinical characteristics.
METHODOLOGY: Heavy metal concentrations in the blood were studied in 7,719 samples from Korea National Health and Nutrition Examination Survey (KNHANES) in 2008-2011.
RESULTS: The geometric means of lead, mercury, and cadmium concentrations in blood were 2.24 ㎍/dL (95% CI: 2.22-2.27), 4.02 ㎍/L (95% CI: 3.94-4.09) and 0.97 ㎍/L (95% CI: 0.96-0.99). Lead and cadmium levels in the blood of current-smokers were higher than non-smokers and former-smokers, but mercury level was highest in former-smokers. The odds ratio of smoking status and lead, mercury, and cadmium concentrations in blood were higher with 3.73, 1.59, and 23.84 in current-smokers than non-smokers. Heavy smokers were found to have correlation with high concentrations of white blood cell (WBC), hemoglobin, hematocrit, and ferritin in blood.
CONCLUSION: This study demonstrated that smoking increased heavy metals (lead, mercury, and cadmium) concentrations, affected hemoglobin, hematocrit, ferritin concentrations and was associated with high WBC counts.