is it bad to smoke tobacco without a filter Anyone joints filter? : r/trees Lung Cancer Risk With Filtered,

American Journal of Public Health 94(2):300-307

(ii) The program participant is no longer in compliance with the customs laws and CBP regulations, including the requirements set forth in 191.192

For substances other than prescription psychotherapeutic drugs, respondents who had ever used the substance (e.g., marijuana) were asked to report when they first used the substance, and respondents who reported first use within a year of their current age were asked to report the year and month when they first used it

Musso, Francesco, Franziska Bettermann, Goran Vucurevic, Peter Stoeter, Andreas Konrad, and Georg Winterer