Examining Heavy Metal Exposure and Respiratory Health in Young Adult Electronic Cigarette Users

Inclusion Criteria: * Aged 18-29 years * Established electronic cigarette (EC) user (participant uses ECs on a daily/weekly basis \[used on ≥ 5 days in past 30-days\] for the past 3 months) * Willing to abstain from nicotine for at least 12 hours before the laboratory visit * Willing to not eat food or drink water/beverages for at least 30 minutes before the laboratory visit \[required for salivary collection\] * Utilize 4th generation EC products (pod-mod or disposable EC products; e.g., JUUL, Hyde) * Must be able to read and write in English Exclusion Criteria: * Recently COVID-19+ (defined as a positive test in the past 30 days) or a recent COVID-19 hospitalization (within the past 6 months) * Attempting to quit the use of ECs * Is pregnant, planning on becoming pregnant and/or breastfeeding \[will be verified using a urine pregnancy test\] * Self-reported severe or significant psychological and/or psychiatric conditions \[e.g., not currently receiving treatment/medication; only past and/or stable conditions will be allowed\] * A history of cardiac events and/or distress within the past 3 months * Diagnosed with a chronic, serious lung disease or current infection (e.g., pneumonia, pulmonary edema) * Are deaf, hard of hearing, or have a severe motor disability