Evaluations will include vital signs, interval smoking history, food frequency questionnaire, exhaled carbon monoxide, blood drawn for chemistry and CBC, peripheral blood harvested and serum aliquoted and saved for future biochemical analysis, urine sample for isoprostane, pregnancy test for females, and exhaled breath condensate. Some visits may also include spirometry with and with out bronchodilators, 24 hour urine collections for NNAL and NNAL-glc quantification, health status assessed using St. George’s Respiratory Questionnaire, the Functional Assessment of Chronic Illness Therapy – Fatigue, the Leicester Cough Questionnaire, the Clinical COPD Questionnaire and smoking related symptoms assessed using the Breathlessness, Cough, and Sputum Scale.