TUESDAY, June 5, 2007 (HealthDay News) -- Even minor exposure to secondhand smoke can harm the cardiovascular system of children, a new study concludes.
Finnish researchers used high-resolution ultrasound to check brachial artery (located in the arm) function of 402 children, age 11, who were divided into three groups based on their blood levels of cotinine, a biomarker for nicotine.
The three groups included: 229 children with no detectable levels of cotinine; 134 children with low blood levels of cotinine (between 0.2 and 1.6 nanograms per milliliter); and 39 with high blood levels of cotinine (more than 1.7 ng/mL).
The study found that children with the highest cotinine levels had significantly reduced brachial artery endothelial function -- a measure of arterial health. Endothelial dysfunction impairs blood vessels' ability to dilate.
"Even modest exposure to tobacco smoke alters endothelial function in children, and may impact early development of atherosclerosis (hardening of the arteries)," study lead author Dr. Katariina Kallio, a research fellow at the Research Centre of Applied and Preventive Cardiovascular Medicine at the University of Turku, said in a prepared statement.
"Endothelial dysfunction relative to (secondhand smoke) may be only partially reversible after cessation to the exposure, suggesting the importance of implementing smoke-free environments for children at home and in public places," Kallio said.
The study findings are published in the June 5 issue of the journal Circulation.
The American Cancer Society has more about secondhand smoke.