CINCINNATI—African-American children may be more susceptible to toxins found in environmental tobacco smoke, and therefore more prone to serious health complications such as cancer, according to a study by University of Cincinnati (UC) researchers.
Researchers found that African-American children with asthma had higher levels of hair and blood cotinine (COAT-e-neen), a product of nicotine metabolism, when compared with Caucasian children.
Stephen Wilson, MD, author of the study to be published in the March issue of the journal Chest, said average blood serum levels of the African-American children studied were 32 percent higher in cotinine than those of Caucasian children.
Although health effects of cotinine are not well understood, the fact it is derived only from nicotine makes it a good indicator of how much cigarette smoke enters the body. Many other chemicals found in tobacco smoke, however, are known to be harmful.
“African-American children with asthma had hair cotinine levels that were almost four times that of their white counterparts,” Wilson said.
Wilson, an assistant professor of medicine and pediatrics at UC, said this finding shows African-American children handle tobacco smoke differently.
“The difference could make them more susceptible to other compounds found in environmental tobacco smoke,” he said.
The study examined a biracial sample containing 55 percent African-American children, aged 5 to 12, who suffered from asthma and were exposed regularly to tobacco smoke.
Researchers measured cotinine levels in blood serum and hair as well as environmental tobacco smoke in the main activity room in each residence.
Wilson said the main goal of the study was to test whether high-efficiency particulate air cleaners reduced children’s exposure to environmental tobacco smoke in a household where five or more cigarettes were smoked per day.
However, these researchers uncovered more.
“Previous studies have shown differences in cotinine levels among active smokers,” Wilson says. “We extended this work by showing large differences in cotinine levels among children exposed to environmental tobacco smoke.
“This raises questions as to whether there are differences in exposure or metabolism for other ingredients of tobacco that could ultimately lead to the development of cancer and other tobacco-associated diseases.”
Wilson said race was an important variable since African-American children suffer from higher rates of tobacco-related disorders, for example, asthma, sudden-infant death syndrome and low birth weight.
He said more research needs to be done to assess racial differences in exposure to other elements of tobacco.
“We need to understand how certain populations—particularly those groups who are most susceptible—respond to environmental tobacco smoke so we can reduce and ultimately eliminate disparities in these health outcomes,” he said. “These results raise questions as to whether there are racial differences in other tobacco toxins, particularly those compounds that are known to cause cancer.”
Wilson’s research team included UC faculty members Robert Kahn, MD, Jane Khoury, PhD, and Bruce Lanphear, MD, MPH, all of Cincinnati Children’s Hospital Medical Center.
The study was funded by a grant from the National Heart, Lung, and Blood Institute, the Robert Wood Johnson Generalist Physician Faculty Scholars Award and the University of Cincinnati Department of Internal Medicine.