It is the first human study to detail the way certain substances  in tobacco cause DNA damage linked to cancer.
Stephen  S. Hecht and colleagues have pointed out that evidence  indicates  harmful substances in tobacco smoke termed polycyclic aromatic   hydrocarbons, or PAHs, are one of the culprits in causing lung cancer.
Until  now, however, scientists had not detailed the specific way  in which  the PAHs in cigarette smoke cause DNA damage in humans.
The  scientists added a labeled PAH, phenanthrene, to cigarettes  and  tracked its fate in 12 volunteers who smoked the cigarettes. They found  that  phenanthrene quickly forms a toxic substance in the blood known to  trash DNA,  causing mutations that can cause cancer.
The  smokers developed maximum levels of the substance in a time  frame that  surprised even the researchers: Just 15-30 minutes after the   volunteers finished smoking.
Researchers said the effect is so fast that it’s equivalent to  injecting the substance directly into the bloodstream.
"It  is the first to investigate human metabolism of a PAH  specifically  delivered by inhalation in cigarette smoke, without interference by   other sources of exposure such as air pollution or the diet. The results   reported here should serve as a stark warning to those who are  considering  starting to smoke cigarettes," noted the article.
The findings were reported in the journal Chemical Research in  Toxicology, published by the American Chemical Society. (ANI)
Courtesy - The Island