Donald P. Tashkin, MD, Director of the Pulmonary Function Laboratories at the University of California, Los Angeles (UCLA), reported at the June 2005 meeting of the International Cannabinoid Research Society on his as-yet unpublished study of 1,209 Los Angeles residents aged 59 or younger with cancer:

“We found absolutely no suggestion of a dose response [i.e. marijuana smoking leads directly to lung cancer].

The data on tobacco use… revealed a very potent effect and clear dose-response relationship — a 21-fold greater risk of developing lung cancer if you smoke more than two packs a day.

So, in summary, we failed to observe a positive association of marijuana use and other potential co-founders.”

June 2005