P&S Journal: Winter 1995, Vol.15, No.1
Tobacco Smoke and Preschool Children of Smokers
A study of biological indicators of environmental tobacco smoke (ETS) exposure in preschool children of smoking and non-smoking mothers, reported in the September 21 Journal of the National Cancer Institute, found a statistically significant elevation in levels of two biomarkers in children whose mothers smoked and in levels of one biomarker in children of non-smokers regularly exposed to ETS by others in the home compared with the unexposed.
Dr. Florence G. Crawford, assistant professor of pediatrics at Harlem Hospital Center, and Dr. Frederica Perera, associate professor of public health (epidemiology), led a research team that studied blood levels of cotinine (a nicotine metabolite) and polycyclic aromatic hydrocarbons (PAH, a tobacco smoke carcinogen also found environmentally) carried by blood protein albumin in 87 Hispanic and African-American mothers and 87 of their children ages 2 to 5. Mothers in the study were from northern Manhattan and were their children's primary caretaker, spending at least 70 percent of their time in the home. The mothers were interviewed to assess their smoking history; other exposure to tobacco smoke in the home; and environmental, dietary, and workplace exposure to PAHs. The children's exposure histories and health histories of mother and child also were documented. Following the interview, blood samples were drawn and analyzed for cotinine and PAH-albumin levels.
Both cotinine and PAH-albumin were significantly higher in children whose mothers smoked than in children of non-smoking mothers. While maternal smoking was the greatest contributor to elevated biomarkers in the children, smoking by other household members and visitors also was associated with a significant increase in children's cotinine levels. African-American children had somewhat higher levels of cotinine and PAH-albumin than Hispanic children at similar smoking exposure levels, though the small sample size prevented firm conclusions regarding ethnic differences in ETS effects. Among the children of smokers, a significant dose-response relationship was identified between cotinine (but not PAH-albumin) and the number of cigarettes smoked per day by the mother. None of the mothers who smoked (31 total) smoked as much as one pack of cigarettes per day; the average was 10 cigarettes daily. Like their children, the smoking mothers' cotinine and PAH-albumin levels were elevated compared with non-smoking mothers, and cotinine was strongly correlated with the number of cigarettes smoked daily.