The study is the first on humans to track how substances in tobacco cause DNA damage, and appears in the peer-reviewed journal Chemical Research in Toxicology, issued by the American Chemical Society.Using 12 volunteer smokers, scientists tracked pollutants called PAHs, or polycyclic aromatic hydrocarbons, that are carried in tobacco smoke and can also be found in coal-burning plants and in charred barbecue food.They followed one particular type -- phenanthrene, which is found in cigarette smoke -- through the blood and saw it form a toxic substance that is known to "trash DNA, causing mutations that can cause cancer," the study said.
"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," the study said. Lung cancer kills about 3,000 people around the world each day, and 90 percent of those deaths are attributable to cigarette smoking.
The research was funded by the National Cancer Institute.