Low Level Smoke Exposure Risk

Low levels of smoke exposure could cause genetic abnormalities in airway cells.
The Los Angeles Times (8/20, Kaplan) "Booster Shots" blog reported, "Smoking a pack (or two) of cigarettes each day is obviously not good for your lungs. But for those who enjoy an occasional smoke, an obvious question is, 'How many cigarettes can I smoke before I start to do some damage?'" New research from Cornell indicates there's a "sobering answer: Zero."
Even "secondhand smoke" does harm, reports CNN (8/23). "Sometimes it's hard to avoid being around family members who smoke at home or friends who light up at bars. But it's worth it," because "just a small amount of smoke can be detrimental to your health."
Indeed, "public-health bans on smoking have been fueled by strong population-based data that links exposure to secondhand cigarette smoke and a higher incidence of lung diseases, such as emphysema and even lung cancer, but [they] do not establish a biological cause for the correlation," Time (8/20, Park) reported. "Now, for the first time, researchers can point to one possible cause: the passive recipient's genes are actually being affected." Before reaching that conclusion, investigators "devised a study in which 121 volunteers -- some of whom smoked and some of whom had never smoked -- agreed to have samples of their airway cells studied for genetic activity."
The team eventually discovered that "when exposed to smoke, the genes get turned on and off abnormally," WebMD (8/20, Doheny) reported. "The cell is crying out at a biological level, saying, 'Something's wrong. I'm being stressed here.'" Altogether, "about 370 different genes sense the smoke...and turn off and on in the area."
And, "there was no level of nicotine or cotinine, no matter how small, that did not produce genetic abnormalities," HealthDay (8/20, Reinberg) noted. Yet, "knowing which genes are damaged could provide targets for new drugs that could protect the lungs," the authors wrote in the American Journal of Respiratory and Critical Care Medicine. Dr. Norman H. Edelman, of the American Lung Association, "applauded the study," saying, "I like this one, because it cleverly uses molecular biology to answer a very important question, one that I get asked very often."