Comparison of biomarkers of exposure among US adult smokers, users of electronic nicotine delivery systems, dual users and nonusers, 2018–2019May 24, 2023May 24, 2023https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10163269/?fbclid=IwAR2ftvFV6mySHe3HmGPMsJK_N1IJp-IWltXYpcYN27cp3OyjLnbbgEoYyHELeave a Reply Cancel replyYour email address will not be published. Required fields are marked *Name * Email * Website Comment * Save my name, email, and website in this browser for the next time I comment. ΔThis site uses Akismet to reduce spam. Learn how your comment data is processed.