This came from www.maps.org , the web site of the Multidisciplinary
Association for Psychedelic Studies (address at end.) It was in their
Spring '96 newsletter; join them to get the hard copy, including
photos of the bongs tested.
Marijuana Water Pipe and Vaporizer Study
---------------------------------------------------------------------------
Dale Gieringer, Ph.D.
Contrary to popular impression, waterpipes don't necessarily protect
smokers from harmful tars in marijuana smoke, according to a new study
sponsored by MAPS and California NORML (National Organization for the
Reform of Marijuana Laws). The reason is that waterpipes filter out more
psychoactive THC than they do other tars, thereby requiring users to smoke
more to reach their desired effect. The study does not rule out the
possibility that waterpipes could have other benefits, such as filtering
out gases, but it suggests that other methods, such as the use of high
potency marijuana, vaporizers, or oral ingestion are needed to avoid
harmful toxins in marijuana smoke.
Seven Devices Tested
The study, which was supported by the Drug Policy Foundation and private
donors, was conducted at a research lab with expertise in the analysis of
various chemical properties of tobacco and marijuana. Researchers tested
the smoke from seven different sources: a regular rolled joint, a joint
with a cigarette filter, three different waterpipes, and two vaporizers,
designed to heat marijuana to a temperature where psychoactive vapors form
without producing smoke. The waterpipes included a standard bong (Picture
#1), a small portable device with a folding pipestem (Picture #6), and a
battery-operated model with a motorized paddle to thoroughly mix the smoke
in the water (Picture #3). The first vaporizer (Picture #5), commercially
produced in Canada, consisted of a battery-powered metal hot plate inside a
jar to trap the marijuana vapor. The second (Picture #4) was a homemade,
hybrid apparatus, in which vapors were produced by a hot air gun and then
drawn through a beaker of water, thereby combining vaporization with water
filtration. The smoke was produced from standard NIDA-supplied marijuana
drawn through a smoking machine adjusted to mimic the puff length of
marijuana smokers.
Focus: Cannabinoid/Tar Ratio
The study focused on two key components of the smoke: (1) total solid
particulates, or tars, which are noxious waste by-products of burning leaf
like those from tobacco; and (2) cannabinoids, the chemicals distinctive to
marijuana, including its major psychoactive ingredient,
delta-9-tetrahydrocannabinol (THC), and its two commonest chemical
relatives, cannabinol (CBN) and cannabidiol (CBD), which are only weakly
psychoactive but may have medical benefits.
Like tobacco, marijuana tars are rich in carcinogenic compounds known as
polycyclic aromatic hydrocarbons, which are a prime culprit in
smoking-related cancers. 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.
One way to do this is to increase the THC potency of the marijuana.
Assuming smokers adjust their smoke intake to the cannabinoid dosage, the
higher the concentration of cannabinoids, the lower the amount of tars they
are likely to consume.
Another strategy is to try to reduce the tars in the smoke with some kind
of filtering device. Obviously, this is beneficial only to the extent that
THC isn't also reduced, thereby inducing users to smoke more to compensate.
A major aim of the study was to determine the efficacy of various smoking
devices at reducing the concentration of tars relative to cannabinoids. The
performance of each device was accordingly rated in terms of the
cannabinoid-to-tar ratio in its smokestream.
Joints and Waterpipes
Surprisingly, the unfiltered joint outperformed all devices except the
vaporizers, with a ratio of about 1 part cannabinoids to 13 parts tar. This
disturbingly poor ratio may be explained by the low potency of the
NIDA-supplied marijuana used in the study, which was around 2.3%.
Disappointingly, waterpipes performed uniformly worse than the unfiltered
joint. The least bad waterpipe, the bong, produced 30% more tar per
cannabinoids than the unfiltered joint. Ironically, the pipe with the
electric mixer scored by far the worst of any device. This suggests that
water filtration is actually counterproductive, apparently because water
tends to absorb THC more readily than noxious tars. Like the waterpipes,
the cigarette filter also performed worse than the unfiltered joint, by
about 30%. Researchers speculate this is because cannabinoids are
exceptionally sticky and adhere to other solids. Hence, any filtration
system that picks up particulates is likely also to screen out
cannabinoids.
(continued next post)
--- PPoint 2.00
---------------