Race Affects Tobacco Absorption In Children
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
"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
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
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.
No racial differences were reported in levels of ETS exposure outside
of the home or in air nicotine levels at the 6-month or 1-year study
visits. But, results indicated that while African-American children spent
less time exposed to ETS, they showed significantly higher levels of
cotinine compared to Caucasian children. On average, serum cotinine levels
in the African-American participants were 32 percent higher than in the
Caucasian participants, and hair cotinine levels were 4 times that of the
"Previous studies of adult smokers, as well as cross-sectional studies
of nonsmokers have demonstrated similar racial differences in serum
cotinine, however, we were surprised at the magnitude of the racial
differences in the hair continine," said Dr. Wilson. "African-American
children may "handle" environmental tobacco smoke differently than white
children, so these results raise questions as to whether there are racial
differences in other tobacco toxicants, as well."
"Exposure to tobacco smoke is dangerous for everyone, regardless of age
or race," said Mark J. Rosen, MD, FCCP, President of the American College
of Chest Physicians. "These findings underline the importance of
eliminating environmental tobacco smoke in every setting, especially those
where children are present."
CHEST is a peer-reviewed journal published by the ACCP. It is available
online each month at