Thursday, July 2, 2009
Marijuana Smoking Does Not Cause Lung Cancer, UCLA Expert Dr. Tashkin Concludes Protective Effect "Not Unreasonable"Marijuana smoking -"even heavy long-term use"- does not cause cancer of the lung, upper airways, or esophagus, Dr. Donald Tashkin reported at this year's meeting of the International Cannabinoid Research Society...
Stephen Sidney examined the files of 64,000 Kaiser patients and found that marijuana users didn't develop lung cancer at a higher rate or die earlier than non-users. Of five smaller studies on the question, only two -involving a total of about 300 patients- concluded that marijuana smoking causes lung cancer. Tashkin decided to settle the question by conducting a large, population-based, case-controlled study."Our major hypothesis," he told the ICRS, "was that heavy, long-term use of marijuana will increase the risk of lung and upper-airways cancers."
The Los Angeles County Cancer Surveillance program provided Tashkin's team with the names of 1,209 L.A. residents aged 59 or younger with cancer (611 lung, 403 oral/pharyngeal, 90 laryngeal, 108 esophageal). Interviewers collected extensive lifetime histories of marijuana, tobacco, alcohol and other drug use, and data on diet, occupational exposures, family history of cancer, and various "socio-demographic factors." Exposure to marijuana was measured in joint years (joints per day x years that number smoked)...
There was time for only one question, said the moderator, and San Francisco oncologist Donald Abrams, M.D., was already at the microphone: "You don't see any positive correlation, but in at least one category, it almost looked like there was a negative correlation, i.e., a protective effect. Could you comment on that?" [Abrams was referring to Tashkin's lung-cancer-only data for marijuana-only smokers in 1-10 j-yrs category.] "Yes," said Tashkin. "The odds ratios are less than one almost consistently, and in one category that relationship was significant, but I think that it would be difficult to extract from these data the conclusion that marijuana is protective against lung cancer. But that is not an unreasonable hypothesis."
And this one...
State rules marijuana smoke is a carcinogen, may require dispensaries to post warnings
Joints and baggies sold at California's medical marijuana dispensaries will soon carry a new warning label. Next to tags like "Purple Haze" and "White Widow" will be the advisory: Contents may cause cancer when smoked.
On Friday, California added marijuana smoke to its official list of known carcinogens, joining the ranks of arsenic, asbestos and DDT. Pot brownies, lollipops and other non-inhalables are not affected by the new ruling.
Scientists found the pungent smoke shares many of the same harmful properties as tobacco smoke, warranting its inclusion on the Proposition 65 warning list. The law requires the state to publish a list of chemicals known to cause cancer or reproductive toxicity, and businesses and government agencies must post warnings when they use such chemicals or sell products containing them.
"Marijuana smoke is a mixture of different chemicals, and a number of those were already on the Prop. 65 list," said Allan Hirsch, chief deputy director of the state Office of Environmental Health Hazard Assessment, which made the designation.
Okay, that last one was boring too, but it was also absolutely insane. Ignoring the science showing pot may prevent cancer, they declare it a carcinogen because it "shares many of the same harmful properties as tobacco smoke." That doesn't prove anything. Here's how their logic works.You can make orange juice from oranges. Oranges are a fruit. Apples are also a fruit, therefore you can make orange juice out of apples.