First correspondence with BLF over Lung Cancer and Cannabis | In the News | Forum

Hello Alistair,
My name is Des Humphrey, I am a co-founder of NORML-UK, a group that wishes promote a sensible and responsible policy when it comes to the reform of cannabis laws.
We believe in scientific based research and evidence, not hearsay and speculation. After listening to Dame Helena Shovelton on radio Sheffield this morning I would like further information regarding the source and study your information was obtained from, specifically your assertion that 1 cannabis
joint is the equivalent to 20 cigarettes and the evidence that suggests that eating cannabis causes heart attacks, I will be very interested in hearing from you asap
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Kind Regards
Des Humphrey

Dear Alistair,
Thank you kindly for replying so fast, however after going through all the relevant information I find it hard to believe that the British Lung Foundation are trying to instill more scare mongering like they did in 2002. Most of the same studies and reports that you have used are the same as you did back in 2002.

Today there is much more information available.

Dr Donald Tashkin at the UCLA has been involved in several 20 year studies on the impact of smoking cannabis on the lungs, heart and the chances of developing cancers. The studies were funded by the United States Federal Government and took place from between 1985 and 2005. They concluded that:

“The heaviest marijuana users in the study had smoked more than 22,000 joints, while moderately heavy smokers had smoked between 11,000 and 22,000 joints.
While two-pack-a-day or more cigarette smokers were found to have a 20-fold increase in lung cancer risk, no elevation in risk was seen for even the very heaviest marijuana smokers.
The more tobacco a person smoked, the greater their risk of developing lung cancer and other cancers of the head and neck. But people who smoked more marijuana were not at increased risk compared with people who smoked less and people who didn’t smoke at all.”

This may well be why over 40% of young people today correctly believe that cannabis is much less harmful that cigarettes, which are labeled accordingly. Under the black market cannabis cannot be labeled as more harmful than tobacco even if it were the case. Even FRANK advice that cannabis is much less harmful than tobacco and if you are going to smoke it then they advise you do so in a water bong.

The comment that ‘eating cannabis can cause heart attack’, I do believe that if you eat anything at all the risk of heart attack increases by x4 even having a hot bath increases the risk by x10 http://www.diabetes.co.uk/news…..11141.html

For the comment about cannabis “Young people in particular are smoking cannabis unaware that, for instance, each cannabis cigarette they smoke could increase their chances of developing lung cancer by as much as an entire packet of 20 tobacco cigarettes.” this comment is so misleading and needs to be subtracted with immediate effect.

It is said that those who smoke cannabis inhale more deeply and therefore cause more damage to the lung – this last part is only true if it is mixed with tobacco. Telling people to smoke cannabis without tobacco would be a much more sensible approach,. The reason this would work is because there are a large number of cannabis consumers that cut it with tobacco to reduce cost but don’t smoke cigarettes alone. Prohibition has caused this problem by increasing the price of cannabis. Most consumers say they would stop tobacco if the price was not controlled by the back market and funded criminals. In 17 states of America and Washington DC there is regulated access to cannabis for patients who can afford to smoke pure.

Cannabis consumption has been around for 5000 years of recorded history and has yet to kill someone, so instead of scaring people why not try a different approach and advise about the safest way of doing it. you even identify that people are smoking it in much higher concentrates in the report but where are the bodies and death tally of those who have dies of cannabis induced cancer to fulfil the 20x higher risk claim?

It is a well-known fact that adulterated cannabis is the cause of harm caused by cannabis. Sand, glass, iron filings, chemical sprays and fiberglass just to name a few of the things that prohibition has introduced the a cannabis consumers life, if you remove prohibition and allow a legitimate industry to take its place then they harms can be avoided almost entirely.

Vaporization of cannabis with one of the many available mechanisms on the market now allow cannabis consumers to avoid combustion (if they can afford the price tag). These devices are even recommended by the Dutch Government and health authorities for patients prescribed Dutch Medicinal Cannabis Bedrocan. It is reasonable for me to add that this variety is available in the Coffeeshops as Super Silver Haze and is a favorite among cannabis smokers in the UK.

We at NORML UK completely agree that inhaling combusted plant material of any kind or breathing in any kind of smoke can be harmful to the lungs and carries its risks, but to try and scare people into not consuming cannabis will not work.

Something that has to be understood with this kind of hysteria inducing publication is the confusion it creates when the public are being eased into its use as a medicine. GW Pharmaceuticals are using it for pain in cancer patients because cancer patients smoke cannabis for relief, they have even about to start trials in Barcelona this year to actively treat cancer with cannabis because cancer patients have been using cannabis oil for decades and many with success to treat their cancers. Many use it as an adjunctive medication to chemotherapy to reduce nausea, pain and induce an appetite that will help them keep their strength.

Please find the time to go through a few links I have provided so you to can become aware of some more interesting facts about cannabis and its medicinal properties.

http://www.marketwatch.com/sto…..2012-06-06
http://jama.jamanetwork.com/ar…..8;page=173
http://phoenixtears.ca/make-th…..-medicine/
http://www.ncbi.nlm.nih.gov/pu…..d/18238947
http://erj.ersjournals.com/con…..3/815.long
http://www.sciencedaily.com/re…..193338.htm

Yours Sincerely

Des Humphrey
NORML UK

Dear Des,

Many thanks for your email, which makes a number of well-informed and valid points, which I have attempted to address in turn.

Firstly, with regards to the Tashkin study you refer to (“Marijuana use and the risk of lung and upper aerodigestive tract cancers”, Hashibe et al, 2006), this paper was indeed reviewed as part of our report. However, it is important to consider the paper in the context of other data available. In contrast to the findings of this study, a broader range of research has found that cannabis smoke contains known carcinogens (cancer-causing agents), that cannabis smoke causes DNA damage of the type seen in lung cancer, and that smoking cannabis is associated with a significantly increased risk of lung cancer. References for all these studies can be found in our report, which is free to download from our website. Overall, looking at the sum of all the laboratory and epidemiological evidence available, the report’s authors and independent peer reviewers concluded that, while important to acknowledge this paper, it would be irresponsible for us to not report the risks of developing lung cancer highlighted in a significant number of other studies.

With regards to the legal status of cannabis, I should clarify that we have never, and will not, take a stance on either side of this debate. Our report solely recommends more research into, and greater public awareness of, the health risks involved in smoking cannabis, and makes no recommendations on its legality or classification. I should also add that highlighting research which shows that cannabis may increase the risk of developing lung cancer more than tobacco cigarettes should not be misconstrued as a broad statement that cigarettes are less harmful. We are clear that tobacco is harmful to those who smoke it, and campaign to cut the number of people affected by cigarette smoke.

While it is of course possible that other activities can increase the risk of heart attack, our report looked at the impact of cannabis on the health of users. As such, it would have been remiss of us not to report where research had shown an impact on the risk of heart attacks.

Our report references research data showing that the risk of lung cancer could be up to 20 times greater in cannabis cigarettes than tobacco cigarettes, so again it would be remiss of us not to report it. While you are also correct to point out that there are no recorded deaths directly attributed to a cannabis ‘overdose’, if one’s risk of lung cancer does increase as a result of smoking cannabis, then it is possible that smoking cannabis could lead to a death – the majority of people with lung cancer do die from the disease.

With regards to your comments that cannabis being several times stronger should have increased the number of deaths by a similar amount, it should be noted (as I’m sure you know) that the strength of cannabis is commonly measured in the concentration of THC, which (as far as research has yet shown) is not the active ingredient with regards to the development lung cancer. In any case, it should also be noted that the rise in cannabis strength and use is a relatively recent phenomenon. Diseases like lung cancer have a long lag period before presenting - for instance, the rise in lung cancer cases seen in recent years, particularly among women, is commonly believed to be the result of a rise in smoking cigarettes in the 1970s. One of the reasons for this report was to minimise any possible damage that might be done in future by smoking cannabis now.

I’ve passed your comments regarding vaporisation to our research team. I understand that there is currently very little research data on the health impact of using cannabis this way, so it would be difficult to comment as to its relative health impact, but this would certainly make for an interesting area for future research.

With regards to the websites you sent through, most of these studies, if not all (it is difficult to ascertain from news reports whether a study was ever published in a peer-review journal and under what title) were referenced in our report. One of the studies is of course the very study that suggested the risk of lung cancer is up to twenty times greater in cannabis than in cigarettes, which I assume you emailed me by way of context for the refutation published in the European Respiratory Journal? If so, it should be noted that the views expressed in that letter are those of three researchers who had written to the journal, rather than those of the Journal itself. If the Journal has been sufficiently convinced of the case put forward in this letter, it would have withdrawn the paper. That this did not happen with this, nor any paper reviewed for our report, means they are part of the existing peer-reviewed research base and therefore needed to be considered for our report.

With regards to the JAMA paper you emailed me (‘Association between Marijuana Exposure and Pulmonary Function Over 20 Years’, Pletcher et al, 2012), this study found that lung function was not impaired by smoking cannabis. These data are relevant for obstructive lung diseases like COPD, and as a result of this and other data, we clearly state in our report that there is no firmly established link between cannabis use and obstructive lung diseases. However, as the study referred solely to lung function, it does not contradict any comments made elsewhere in the report relating to lung cancer or other conditions.

Overall, it was not our intention to scare people, but to raise awareness of the potential health risks as outlined by the evidence. We welcome the informed and rational approach you have taken in critiquing our report, however, and will be in touch if we review the report in light of new research data in future.

Best wishes,

Alistair

Alistair Martin
Press and Campaigns Manager
m: 07500 334 165

British Lung Foundation
73-75 Goswell Road
London
EC1V 7ER
http://www.lunguk.org