Carcinogen and Toxicant Exposure Among Young Adults Who Co-Use E-cigarettes and Cannabis (Co-Tox Study)

Subjects will asked which type of recruitment material they've seen when completing the screening survey

subjects will choose location when coordinator calls to schedule appointment

Self reported measure of current cannabis use that contains 30 questions assessing quantity, frequency of use and method of consumption in the past 30 days.

A 22-item questionnaire measuring e-cigarette dependence. Higher scores indicate greater dependence.