The purpose of this research study is to better understand how people respond to cancer-causing chemicals in cigarette smoke. Some people are able to get rid of these chemicals as harmless agents while others suffer damage to their cells that can ultimately result in cancer. We hope to develop a better understanding of how we can identify the people who are in danger of getting cancer. Participants will complete questionnaires regarding their health and smoking history. We will take blood samples to look at genes which determine how the body breaks down some tobacco-related toxins. Participants will be given a small amount of liquid to drink, containing alcohol, water, and a compound called deuterated phenanthrene (DP), which is found in cigarette smoke and in the environment. Phenanthrene is non-toxic and does not cause cancer, but this compound is broken down by the body in the same way as cancer-causing agents. We will follow the pathway of this compound as it is broken down in the body.