SAN FRANCISCO, May 1 (UPI) -- U.S. researchers show that exposure to environmental tobacco smoke, even at extremely low levels, is associated with behavior problems in children.
Kimberly Yolton, a researcher at the Children's Environmental Health Center at Cincinnati Children's Hospital, examined 225 children and pre-teens exposed to at least five cigarettes a day.
To measure exposure to environmental tobacco smoke, Yolton measured levels of cotinine in the children's blood. Cotinine is a substance produced when nicotine is broken down by the body and can be measured in blood, urine, saliva and hair. It is considered the best available marker of environmental tobacco smoke exposure.
Yolton found a relationship between cotinine levels and increases in acting out; increases in holding things in, often manifested by anxiety and depression; increases in behavior problems as rated by parents and behavior and school problems as rated by teachers; and decreases in the ability to adapt to behavior problems.
"The greater the exposure to tobacco smoke, the greater the problems these children had," Yolton told the annual meeting of the Pediatric Academic Societies in San Francisco.
