are in Research
shows vaporizer can drastically reduce toxins in marijuana smoke
NORML Release - May 2 2003
toxins in marijuana smoke can be effectively avoided by a vaporization device,
according to a new study by California NORML and MAPS (Multidisciplinary Association
for Psychedelic Studies) with support from a grant from the MPP (Marijuana Policy
study, conducted by Chemic Labs in Canton, Mass., tested vapors from cannabis
heated in an herbal vaporizer known as the Volcano (manufactured by Storz &
Bickel GmbH&Co. KG, Tuttlingen, Germany; http://www.storz-bickel.com)
and compared them to smoke produced by combusted marijuana. The Volcano is designed
to heat material to temperatures of 130° to 230° C (266° to 446°
F) where medically active vapors are produced, but below the threshold of combustion
where smoke is formed.
vapors from the Volcano were found to consist overwhelmingly of THC, the major
active component in marijuana, whereas the combusted smoke contained over 100
other chemicals, including several polynuclear aromatic hydrocarbons (PAHs), carcinogenic
toxins that are common in tobacco smoke. The respiratory hazards of marijuana
and tobacco smoke are due to toxic byproducts of combustion, not the active ingredients
in the plant, known as cannabinoids.
study suggests that medical marijuana patients can avoid the respiratory hazards
of smoking by using a vaporizer. In its 1999 report on medical marijuana, the
Institute of Medicine recommended against long-term use of smoked marijuana because
of the health risks of smoking. However, the IOM failed to take account of vaporizers.
studies have found that vaporizers can reduce harmful toxins in cannabis smoke.
However, this is the first study to analyze the gas phase of the vapor for a wide
range of toxins. A previous NORML/MAPS study conducted by Chemic Labs found that
a vaporizer known as the M-1 Volatizer (http://www.volatizer.com)
completely eliminated three specific toxins (naphthalene, benzene and toluene)
in. the solid phase of the vapor (D. Gieringer, "Cannabis Vaporization: A
Promising Strategy for Smoke Harm Reduction," Journal of Cannabis Therapeutics
Vol. 1#3-4: 153-70 (2001); http://www.canorml.org/healthfacts/vaporizerstudy1.html
new study used a gas chromatograph mass spectrometer (GCMS) to examine the gas
components of the vapor. .The analysis showed that the Volcano vapor was remarkably
clean, consisting 95% of THC with traces of cannabinol (CBN), another cannabinoid.
The remaining 5% consisted of small amounts of three other components: one suspected
cannabinoid relative, one suspected PAH, and caryophyllene, a fragrant oil in
cannabis and other plants. In contrast over 111 different components appeared
in the gas of the combusted smoke, including a half dozen known PAHs. Non-cannabinoids
accounted for as much as 88% of the total gas content of the smoke.
study used standard NIDA cannabis with 4% THC content. A quantitative analysis
found that the Volcano delivered 46% of the THC into vapor following three 45-second
exposures of the sample to the heat. This compares favorably with the typical
efficiency of marijuana cigarettes as observed in other studies, which depending
on conditions can fall below 25% due to loss of THC in sidestream smoke. An important
feature of the Volcano is that it uses a balloon to capture the vapor, thereby
avoiding leakage to the air. It is possible that higher THC efficiencies could
have been reached with the Volcano by stirring the sample around and exposing
it to more heat.
combusted sample achieved a relatively high THC efficiency of 78% upon complete
combustion. The high efficiency seems due to the fact that the sample was completely
consumed by combustion, and that smoke leakage was effectively prevented by the
laboratory setup. Similar conditions do not obtain under normal circumstances
when a marijuana cigarette is smoked and much of the THC is lost to the air or
left in the unburned "roach."
other cannabinoids , cannabidiol (CBD) and cannabinol (CBN), were detected in
the NIDA cannabis in trace amounts of 0.1%. Both the Volcano and combustion delivered
an apparent increase in CBD and CBN, but the variance of the data was too high
to reach statistically significant conclusions.
believe that the study results lend support for wider use of vaporizers by medical
marijuana patients and researchers. At present, the only FDA-approved method for
administering marijuana to human research subjects is via smoking NIDA cigarettes.
NORML and MAPS are supporting efforts to have vaporizers approved by the FDA.
As a first step in this effort, Dr. Donald Abrams of the University of California,
San Francisco, has submitted a grant proposal to the California Center for Medical
Cannabis Research in San Diego to test the Volcano in human subjects. If the protocol
is funded and the Volcano approved by the FDA for human research, it will be the
first human study using a vaporizer. If the FDA requests additional laboratory
data about the Volcano, additional funding may be necessary.
more information on vaporizers, see
have a copy of the full study from Chemic Laboratories here.