Cannabis does not cause cancer, lung disease, or ill health. Recent reports confirm this.


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Large Study Finds No Link between Marijuana and Lung Cancer: Scientific America, September 2010

CANADA: Pot Doesn't Cause Lung Cancer, Researcher Says: Toronto Star, 12 June 2001

New 126-Page Study, 'NTP Technical Report On The Toxicology And Carcinogenesis Studies Of 1-Trans-Delta-9-Tetrahydrocannabinol, CAS No. 1972-08-3, In F344/N Rats And B6C3F(1) Mice, Gavage Studies': February 1999 from AIDSNEWS

BOSTON, Jan. 30, 1997 (UPI) - The U.S. federal government has failed to make public its own 1994 study that undercuts its position that marijuana is carcinogenic - a $2 million study by the National Toxicology Program. The program's deputy director, John Bucher says the study found absolutely no evidence of cancer. In fact, animals that received THC had fewer cancers. Bucher denies his agency had been pressured to shelve the report, saying the delay in making it public was due to a personnel shortage.

The Boston Globe reported on Thursday 30th January 1997 that the study indicates not only that the main ingredient in marijuana, THC, does not cause cancer, but also that it may even protect against malignancies, laboratory tests on animals show.

The report comes on the heels of an editorial in the prestigious New England Journal of Medicine that favors the controlled medical use of marijuana, and calls current federal policy misguided, heavy-handed and inhumane.


The KAISER PERMANENTE. Prohibition is unhealthy. 1997

Kaiser-Permanente is a large US health-care provider. This study into the effects of long-term smoking of cannabis took 10 years and involved 65,000 people who had received check-ups between 1979 and 1985. The patients were divided into those who had, and those who had not, used cannabis regularly or currently. It was reported that risks associated with cannabis smoking were lower than for tobacco smoking. It also noted that smokers with AIDS had no higher death-rate than non-smokers with AIDS.

The report stated
"Relatively few adverse clinical effects from the chronic use of marijuana have been documented in humans. However, the criminalization of marijuana use may itself be a health hazard, since it may expose the users to violence and criminal activity."
The Kaiser Permanente study - "Marijuana Use and Mortality" April 1997 American Journal of Public Health".

See also: Radioactivity in Tobacco


An 8-year study at the University of California at Los Angeles (UCLA) School of Medicine, concluded that long-term smokers of cannabis do not experience a greater annual decline in lung functions than non-smokers.
Researchers said:
"Findings from the present long-term follow-up study of heavy, habitual marijuana smokers argue against the concept that the continuing heavy use of marijuana is a significant factor for the development of [chronic lung disease]"
"No difference were noted between even quite heavy marijuana smoking and nonsmoking of marijuana."
Volume 155 of the American Journal of Respiratory and Critical Care Medicine 1997


A study of 268 cannabis smokers who, on average, had smoked for 19 years and 31 non-using partners and family members, concluded that the health of the long-term smokers is virtually no different to that of the general population.
Chief researcher Richard Reilly said "The results seem unremarkable...The exceptional thing was that the respondents were unexceptional."
For more information e-mail Jamnes Danenberg

Source: New Scientist (UK)
Pubdate: Sat, 15 Aug 1998
Author: Redford Givens


Michael Roth's "preliminary evidence" suggesting that the THC in marijuana may promote a carcinogenic effect (This week, 25 July, p 16) flies in the face of Louis S. Harris's findings in Analgesic and Anti-Tumor Potential of The Cannabinoids (Medical College of Virginia, 1972) that delta-8 THC, delta-9 THC and cannabinol are quite active as anticancer agents.

At the time of Harris's research, no anticancer agent that was much more potent than delta-9 THC existed and no compounds differentiated between tumour and normal cells the way delta-9 THC does. Considering that delta-9 THC alone increased survival in cancerous rats by 36 per cent, it seems very unlikely that THC promotes carcinogenic effects.

THC's known anticarcinogenic properties are probably the reason the Center for Disease Control in Atlanta, Georgia, has never been able to trace any cancers to marijuana use.

Redford Givens San Francisco

Checked-by: (Joel W. Johnson)

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