The purpose of this study is to use Randomized Controlled Trial (RCT) methods to examine the influence of novel tobacco products on biomarkers of toxicant exposure and disease risk, reports of adverse events, and concurrent use of other tobacco products. In this case, the novel products are one type of electronic cigarette and an imitation cigarette or cigarette substitute.

Inclusion Criteria:

• Age 21-65
• Smoke >9 cigarettes per day for at least 1 year
• Smoke regular filtered cigarettes or machine-rolled cigarettes with a filter
• CO measurement >9 ppm at baseline
• No serious quit attempt in the prior 1 month. This includes use of any FDA approved smoking cessation medication (varenicline, bupropion [used specifically as a quitting aid], patch, gum, lozenge, inhaler, and nasal spray) in the past 1 month as an indication of treatment seeking.
• Not planning to quit in the next 6 months
• Interested in reducing cigarette consumption
• Willing to attend visits weekly and monthly over a 9-month period (not planning to move, not planning extended vacation, no planned surgeries)
• Read and write in English
• Able to understand and consent

Exclusion Criteria:

• Pregnant and/or nursing women
• Unstable or significant medical condition in the past 12 months (Recent heart attack or some other heart conditions, stroke, severe angina including high blood pressure if systolic >159 or diastolic >99 observed during screening).
• Immune system disorders, respiratory diseases (exacerbations of asthma or COPD, require oxygen, require oral prednisone), kidney (dialysis) or liver diseases (cirrhosis), or any medical disorder/medication that may affect participant safety or biomarker data.
• Use of any non-cigarette nicotine delivery product (pipe, cigar, dip, chew, snus, hookah, ECIGs, strips, sticks) in the past 7 days
• Uncontrolled mental illness or substance abuse or inpatient treatment for these in the past 6 months
• History of difficulty providing or unwilling to provide blood samples (fainting, poor veins, anxiety)
• No surgery requiring general anesthesia in the past 6 weeks
• Use of an ECIG for 5 or more days in the past 28 days or any use in the past 7 days
• Use of marijuana or any illicit drug/prescription drugs for non-medical use daily/almost daily, or weekly in the past 3 months per NIDA Quick Screen
• Use of hand-rolled, roll your own cigarettes
• Known allergy to propylene glycol or vegetable glycerin
• Other member of household is currently participating/participated in the study