Casual smoking, low level exposure to smoke causes more harm thanthought

Carol Forsloff -  "No big deal; I just smoke a little," some friend remarks, but casual smokers have been found to be harmed more than they think.


According to new research from
physician-scientists at NewYork-Presbyterian Hospital/Weill Cornell
Medical Center, just having that infrequent cigarette, that occasional
smoke with coffee someplace, or exposed to second-hand smoke that cause
people to be at risk for future lung disease, including lung cancer and
chronic obstructive pulmonary disease.

"Even at the lowest detectable levels of exposure, we found direct
effects on the functioning of genes within the cells lining the
airways," says Dr. Ronald Crystal.  He is the main author of the study
and chief of the division of pulmonary and critical care medicine at
NewYork-Presbyterian/Weill Cornell and chair of the department of
genetic medicine at Weill Cornell Medical College in New York City.

Dr. Crystal goes on to tell us that the genes associated with heavy
smokers are turned on or off even in those that don't smoke much or have
very low level exposure to smoking.

"The genetic effect is much lower than those who are regular smokers,
but this does not mean that there are no health consequences," says Dr.
Crystal.

"Certain
genes within the cells lining the airways are very sensitive to tobacco
smoke, and changes in the function of these genes are the first
evidence of ‘biological disease' in the lungs or individuals."

Dr. Crystal and his collaborators tested 121 people from three
different categories: "nonsmokers," "active smokers" and "low exposure
smokers."  what they found is that there is no level of nicotine or
cotinine that did not also correlate with genetic abnormalities.

"This means that no level of smoking, or exposure to secondhand smoke,
is safe," says Dr. Crystal. He goes on to say that these genetic changes
are like a "canary in a coal mine," warning of potential
life-threatening disease, "but the canary is chirping for low-level
exposure patients, and screaming for active smokers."

Dr. Crystal says that this underlines the need to ban smoking in public places.