Clinical Research Directory

Inclusion Criteria: Vapers Group: 1. Current electronic cigarette (EC) Puff Bar users defined as using EC either daily or occasionally in the past 30 days for at least 6 months, and with 5% nicotine concentration pods. 2. Adults aged 18-40 years Healthy Group: 1. Healthy never smokers, never vapers 2. Adults aged 18-40 years Exclusion Criteria: 1. Current or past smoking of tobacco cigarette (TC) or other tobacco/nicotine products (e.g., smokeless tobacco, Hookah) or marijuana will be excluded from the study. 2. Subjects with self-reported history of chronic health problems including asthma, chronic obstructive pulmonary disease (COPD), morbid obesity (BMI\>40 kg/m2), hypertension or diabetes 3. Pregnant or breastfeeding women