California NORML/MAPS Study Shows Vaporizer Can Drastically
Reduce Toxins in Marijuana Smoke
(Published in the Journal of Cannabis Therapeutics 4(1), 2004)
Harmful 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 Project).
The 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 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.
The 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
The 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.
Previous 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®
(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
The 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.
The 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.
The 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."
Two 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.
Sponsors 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.
For more information , see
California NORML Release May, 2003 - Exerpted from: http://www.canorml.org/healthfacts/vaporizerstudy2.html
"Great spirits have always encountered violent opposition from mediocre minds."
- Albert Einstein