New research suggests that a child's race may be a factor in determining his/her susceptibility to tobacco toxins associated with environmental tobacco smoke (ETS).
The study, published in the March issue of CHEST, the peer-reviewed journal of the American College of Chest Physicians (ACCP), reveals that African American children with asthma, who are exposed to ETS, have significantly higher toxin levels when compared to their Caucasian counterparts.
"African American children suffer from higher rates of tobacco-related disorders, such as asthma, sudden-infant death syndrome, and low birth weight, and we need to know why," said lead author Stephen Wilson MD, University of Cincinnati. "So our goal is to understand how certain populations-particularly those groups who are most susceptible-respond to ETS exposure."
Dr. Wilson and colleagues from the Cincinnati Children's Hospital Medical Center examined 220 tobacco-exposed children with asthma, who had previously participated in the Cincinnati Asthma Prevention study. Researchers studied a bi-racial, community-based sample (55% African American) of children ranging in ages 5 to 12. All of the children had physician-diagnosed asthma, symptoms consistent with persistent asthma, and were exposed to at least five cigarettes per day in or around the home.
Researchers tested for levels of cotinine, a nicotine metabolite, by collecting serum and hair samples at baseline, 6 months, and 1 year. Serum samples accounted for short-term tobacco exposure and hair samples accounted for long-term tobacco exposure.
"Cotinine is a product of nicotine metabolism. When people inhale or ingest nicotine, the body uses proteins to convert it into cotinine," said Dr. Wilson, "and, currently, measuring cotinine in various biologic specimens is a widely used method for assessing nonsmokers' exposure to ETS."
Researchers also avoided reporting parental bias by actively measuring levels of tobacco smoke in the home. Each study participant had a nicotine dosimeter placed in his or her home at baseline and at the 6-month visit. These dosimeters were removed at the 6-month and 1-year visits, and were used to objectively measure each child's level of ETS exposure.