The device loads 10 cigarettes at a time into a chambered wheel attached to a machine that smokes more than two cartons of cigarettes a day. Researchers use unlabeled research cigarettes from the Tobacco Research Institute in Lexington, Kentucky, with no additives or flavoring agents to skew their findings. The smoke generated by the machine is directed into the otherwise clean and well-ventilated cages of a breed of mice with a genetic susceptibility for developing tumors. A medical doctor and professor of toxicology, Witschi does research on acute and chronic pulmonary disease caused by environmental pollutants. After establishing a connection between secondhand smoke and lung tumors in mice, he set out to test the potential of several anti cancer compounds.
Humans are the only animals who smoke, for which they pay a fearsome price.
More than 400,000 Americans die annually from smoking-related causes, including 150,0000 from lung cancer. More than 90 percent of all people diagnosed with lung cancer are current or former smokers. Average survival time after a lung cancer diagnosis is less than a year. In research funded by the National Institute of Environmental Health Sciences, Witschi fed experimental mice diets of special compounds thought to prevent lung cancer. The mice were exposed to cigarette smoke for five months, then placed in clean air for four more months to mimic what happens to people who smoke and then quit.