Second-hand smoke exposure and blood lead levels in U.S. children.

BACKGROUND

Lead is a component of tobacco and tobacco smoke, and smokers have higher blood lead levels than do nonsmokers.

METHODS

We examined the relation between second-hand smoke exposure and blood lead levels in a nationally representative sample of 5592 U.S. children, age 4-16 years, who participated in the Third National Health and Nutrition Examination Survey (1988-1994). Linear and logistic regression modeling was used to adjust for known covariates.

RESULTS

Geometric mean blood lead levels were 1.5 mug/dL, 1.9 mug/dL, and 2.6 mug/dL for children with low, intermediate, and high cotinine levels, respectively. The adjusted linear regression model showed that geometric mean blood lead levels were 38% higher (95% confidence interval [CI] = 25-52%) in children with high cotinine levels compared with children who had low cotinine levels. The logistic regression models showed that children with high cotinine levels were more likely to have blood lead levels >/=10 mug/dL than were children with low cotinine levels (odds ratio [OR] = 4.4; CI = 1.9-10.5).

CONCLUSIONS

Second-hand smoke could be associated with increased blood lead levels in U.S. children aged 4-16 years.