Secondhand Smoke: Damage in Mere Minutes
Just 30 Minutes of Secondhand Smoke Damages the Blood Vessels of Healthy Nonsmokers
April 28, 2008 -- Just 30 minutes in a smoky room can cause profound blood
vessel injury in healthy young adults, greatly increasing the risk of
cardiovascular disease, according to a new study published in the May 6 issue
of the Journal of the American College of Cardiology.
The findings add to the growing body of evidence that suggests that there is
no risk-free level of secondhand smoke. Secondhand smoke, also called
environmental tobacco smoke, contains an array of harmful chemicals, including
nicotine, which have been shown to increase one’s risk for cardiovascular
disease. Exposure to such smoke causes upwards of 50,000 heart disease deaths
in adult nonsmokers every year in the United States, making it a major public
Study author Christian Heiss, MD, currently affiliated with the University
RWTH Aachen in Germany, and colleagues in California evaluated blood vessel
function in healthy, young, nonsmoking adults after they were exposed to a half
hour of secondhand smoke at levels commonly found in public smoking areas. The
study participants also underwent similar evaluations after exposure to
smoke-free air on a different day.
The researchers learned that in healthy nonsmokers, even brief exposure to
secondhand smoke resulted in blood vessel dysfunction and interfered with the
activity of endothelial progenitor cells (EPCs), which are believed to play a
key role in repairing blood vessels. The damage to the EPCs appeared to last as
long as a day.
"Taken together, these findings provide further evidence that even a
very short period of passive smoke exposure has strong, persistent vascular
consequences," the scientists write in the journal article.
Heiss' team is the first to describe the effect of secondhand smoke on EPCs
A decrease in the number and function of EPCs has been linked to
cardiovascular risk factors, including chronic smoking, high blood pressure,
and high cholesterol.
"These findings have significant public health implications and should
raise further awareness of the negative side effects of even brief exposures to
secondhand smoke," Heiss tells WebMD. "Our results help explain
why there is a big immediate drop in heart attacks when smoke-free laws are
In a related editorial, David S. Celermajer, MD, a cardiologist with the
Royal Prince Alfred Hospital in Sydney, Australia, writes that Heiss' current
findings regarding the adverse effect of secondhand smoke on EPC activity, and
not just their number, are worthy of much further investigation, adding that
the team has shown that "where's there's smoke, there is indeed