A breakthrough report published in the journal Science, October 18, 1996, provides the first true molecular evidence conclusively linking components in tobacco smoking to lung cancer. A chemical found in tobacco smoking, benzopyrene, causes genetic damage in lung cells that is identical to the damage observed in the DNA of most malignant tumors of the lungs.
Although scientists have been convinced in the past that smoking causes lung cancer, the strong statistical associations did not provide absolute proof. This paper absolutely pinpoints that mutations in lung cancer cells are caused by benzopyrene.
An average marijuana cigarette contains 30 nanograms of this carcinogen, compared to 21 nanograms in an average tobacco cigarette. (Marijuana and Health, National Academy of Sciences, Institute of Medicine report, 1982.)
This potent carcinogen suppresses a gene that controls growth of cells. When this gene is damaged, the body becomes more susceptible to cancer. This gene, P53, is related to half of all human cancers and as many as 70% of lung cancers.
marijuana smoke contains more of the potent carcinogen benzopyrene than
tobacco smoke. Furthermore, the technique of smoking marijuana by inhaling
deeply and holding the smoke within the lungs presents a chance of much
greater exposure than a conventional
material has been reviewed and commented on by William M. Bennett, M.D.,
Professor of Medicine, Division of Nephrology, Clinical Pharmacology and
Hypertension at Oregon Health Sciences University, Portland, Oregon. Dr.
Bennett, who is listed in "BEST DOCTORS IN AMERICA" states, "The idea of
using smoked marijuana containing these carcinogens as medicine, particularly
for patients who have suppressed immune systems like those with AIDS, should
be unthinkable. Thus, prior to considering marijuana as medicine, one must
abide by the old edict, ‘first do no harm’."