Dr. Eyal Oren and colleagues will be conducting an innovative research project assessing the acceptability among committed smokers of switching to unfiltered cigarettes from filtered cigarettes and will compare doses of nicotine and carcinogens after such switch. The genesis of this project is rooted in recent epidemiological data showing that overall mortality, as well as the incidence of lung cancer, heart disease, and chronic obstructive pulmonary disease, have increased over time suggesting the wide-scale adoption of filtered cigarettes increased rather than decreased the risks of smoking. The project will involve a cross-over clinical trial among smokers to determine changes in their puffing behavior, carcinogen exposures, nicotine exposure, and attitudes toward smoking unfiltered cigarettes if they were no longer able to buy filtered cigarettes. Such research may inform regulatory policy regarding the possibility of banning filters from the US cigarette market because they encourage the uptake of smoking and discourage cessation.