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Vaporizers
for Medical Marijuana (www.1-marijuana-seeds.com)
April
2002
Technology that could alleviate
a major concern about the medical use of marijuana--the harmful effects
of smoking--exists today and is available to the public. But the research
needed to scientifically verify the benefits of these devices, generally
called vaporizers, is proceeding far too slowly, held back by a variety
of constraints.
Vaporizers are designed to release the active ingredients of marijuana, known
as cannabinoids, without actually burning the plant material. This is potentially
important because it is these combustion products rather than the cannabinoids
that are the source of the major health risks associated with smoking, and
those risks have been cited by government officials and others as a major reason
to prohibit or limit use of cannabis as a medicine.
In its report, Marijuana and Medicine: Assessing the Science Base, released
earlier this year, the Institute of Medicine cited the dangers of smoking as
a major drawback. The IOM stated, "Numerous studies suggest that marijuana
smoke is an important risk factor in the development of respiratory disease...
Because of the health risks associated with smoking, smoked marijuana should
generally not be recommended for long-term medical use." The IOM suggested
that researchers concentrate on isolating medically useful cannabinoids and
developing "rapid-onset, nonsmoked cannabinoid delivery systems." Such
systems might be similar to the inhalers used for certain asthma medicines.
While some critics argue that the IOM overemphasized the dangers of marijuana
smoke, all acknowledge that the smoke does indeed contain many of the same
harmful substances as tobacco smoke, including tars and carbon monoxide. "Like
tobacco, marijuana tars are rich in carcinogenic compounds known as polycyclic
aromatic hydrocarbons," wrote California NORML coordinator Dale Gieringer,
Ph.D., in a 1996 article for the newsletter of the Multidisciplinary Association
for Psychedelic Studies (MAPS). "However, cannabinoids themselves are
not carcinogenic. An obvious way to protect smokers' health is therefore to
minimize the content of smoke tars relative to cannabinoids."
A number of vaporizers now on the market appear to do just that. These products
all work on the same basic principle: Taking advantage of the fact that cannabinoids
vaporize at a temperature below that required for marijuana to burn, they use
a heating element to heat the marijuana enough to release the cannabinoid vapors
without setting it on fire.
One of the scientists who reviewed the IOM report prior to its publication,
Harvard assistant professor of psychiatry Lester Grinspoon, M.D., urged the
IOM panel to consider the advantages of such a "non-smoked respiratory
delivery system for the natural plant medicine" rather than putting the
sole emphasis on pharmaceutical product development. The final report, however,
makes no mention of such devices.
Grinspoon, a longtime supporter of medicinal use of marijuana, charges that
the omission is political rather than scientific. "What the report is
doing is trying to pharmaceuticalize away the medical marijuana problem," he
argues. "What they're doing now that they have to grudgingly acknowledge
that this substance has some use [is to say] 'how do we make it a medicine
and keep this prohibition?'"
As for the vaporizers presently available, Grinspoon says, "I've tested
three such devices. There's no question that these things work. They haven't
been tested in the laboratory, but there's no question that cannabinoids come
off and when you look at the [marijuana] in the end it looks just like it did;
it's not burnt." Two medical cannabis club managers consulted by AIDS
Treatment News, Ken Hayes of CHAMP in San Francisco and Jeff Jones of the Oakland
Cannabis Buyers' Cooperative, both shared Grinspoon's enthusiasm for vaporizers.
Vaporizer makers tout two advantages: Avoidance of unhealthful combustion products
and more complete use of the active ingredients. Considerable amounts of cannabinoids,
they say, are wasted when the herb is burned, so vaporizers are more efficient
and economical than conventional smoking.
Unfortunately, the only study to examine these issues scientifically is over
three years old and did not involve the vaporizers currently marketed. The
study, conducted by MAPS and NORML and described in Gieringer's 1996 article,
compared three different water pipes, an early Canadian vaporizer and a homemade
vaporizer/water pipe hybrid to an ordinary joint [marijuana cigarette] and
a joint with a cigarette filter. The smoke produced by each was analyzed for
solid particulates (tars) and 3 major cannabinoids. The various smoking methods
were then rated based on their cannabinoid-to-tar ratio.
Surprisingly, the water pipes performed worse than the unfiltered joint, suggesting
that "water filtration is actually counterproductive, apparently because
water tends to absorb THC [tetrahydrocannabinol, the main psychoactive ingredient
of marijuana] more readily than noxious tars." The vaporizer without the
water pipe component did best, producing a cannabinoid/tar ratio "about
25 percent higher than the unfiltered joint." (An unexplained finding,
though, was that the vapors from the vaporizer contained a higher than normal
amount of cannabinol, a cannabinoid that is less psychoactive than THC but
which may have medicinal benefits. The THC/tar ratio for the vaporizer was
somewhat lower than the unfiltered joint.) Overall, Gieringer concluded that
the study shows great potential for vaporizers but that "more developmental
work needs to be done."
Since that article was published a number of vaporizers have been developed
and sold through a variety of outlets, including head shops, medical cannabis
clubs and on the Internet. Developers of the individual products tend to claim
great benefits and several have ardent fans, but at present there is no scientific
data to verify the efficiency or cannabinoid/tar ratios of these devices.
AIDS Treatment News received a demonstration of two vaporizers, the VaporTech
Vaporizer from Florida-based VaporTech, and the Volatilizer, from California-based
Chirotech. Both products appear to do what they claim to do: vaporize the active
ingredients without actual combustion. Subjectively, users report that the
vapors are notably less harsh than conventional smoke, while being at least
as potent and perhaps more so.
Although everyone we spoke to had a favorite model, there is at present no
scientific data comparing the products with each other or with conventional
smoking. Such a comparison would not be difficult to do with the proper equipment
and lab facilities, and a number of entities are interested in pursuing such
research, including CHAMP and MAPS. Money is one obstacle, notes Gieringer,
as the study would be relatively expensive and there is no pharmaceutical company
to finance it. The firms now marketing vaporizers are all tiny, with nowhere
near the resources of even a medium-sized drug company.
The other obstacle is the continuing prohibition of marijuana, since tobacco
can't be substituted for marijuana in vaporizer tests. Indeed, drug paraphernalia
laws now constrain vaporizer companies from even discussing marijuana in their
publicity materials, and the obstacles to medical marijuana research remain
high. Chuck Thomas of the Marijuana Policy Project notes that a well-publicized
easing of restrictions announced earlier this year was only a small step in
the right direction. "Health and Human Services still makes it unnecessarily
difficult to do medical marijuana research," he says. "The HHS guidelines
still say a special Public Health Service review is necessary. The question
is, why? You can study thalidomide without a PHS review, and I don't think
anyone in their right mind believes that marijuana is more dangerous than thalidomide."
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