Does regular marijuana smoking cause COPD, Emphysema and/or Lung Cancer?

Dr. Donald Tashkin, Medical Director of the Pulmonary Function Laboratory and Professor of Medicine at the University of California at Los Angeles, presented the results of twenty-five years of observations (on cannabis smokers; tobacco smokers; a combination of the two; and non-smokers) at our Fifth National Clinical Conference on Cannabis Therapeutics, held in April, 2008 in Pacific Grove, CA. His presentation is viewable here in three parts: 

One well documented group of patients using "joints" as a delivery device for Cannabis medicine receives an average of three hundred "marijuana cigarettes" per month - grown by the U.S. federal government and provided under the "Compassionate Investigational New Drug Program" - See the Missoula Chronic Cannabis Use Study 

 Suggested Reading:

Hashibe, M., Morgenstern, H., Cui, Y., Tashkin, D. P., Zhang, Z. F., Cozen, W., et al. (2006). Marijuana use and the risk of lung and upper aerodigestive tract cancers: results of a population-based case-control study. Cancer Epidemiol Biomarkers Prev, 15(10), 1829-1834.

Russo, E. B., Mathre, M. L., Byrne, A., Velin, R., Bach, P. J., Sanchez-Ramos, J., et al. (2002). Chronic cannabis use in the Compassionate Investigational New Drug Program: An examination of benefits and adverse effects of legal clinical cannabis. Journal of Cannabis Therapeutics, 2(1), 3-57. 

Additional Research:

Tashkin, D. P. (2005). Smoked marijuana as a cause of lung injury. Monaldi Arch Chest Dis, 63(2), 93-100.

Melamede, R. J. (2005). Cannabis and tobacco smoke are not equally carcinogenic. Harm Reduct J, 2(1), 21.