||Numerous vaporizers, designed to minimize smoke inhalation and health risks, have been marketed in recent years. Models include the electric Volcano and Easy-Vap, as well as the flame-powered VaporGenie. Detailed analysis of cannabis vapor produced by the Volcano confirmed that it vaporizes cannabinoids while generating significantly fewer toxins than burning.1|
Vaporizers are able to release THC from cannabis without creating smoke because the boiling point of THC—about 200° C (392° F)—is significantly lower than the combustion temperature of the plant material.2 However, the melting point of salvinorin A, the principal psychoactive chemical in Salvia divinorum, is significantly higher at 238-244° C (460-464° F).3,4 According to S. divinorum expert Daniel Siebert, the boiling temperature has not yet been conclusively determined. He notes:
When this compound is heated beyond its melting point, it gradually evaporates. The rate of evaporation increases with temperature. It can evaporate quickly and completely without ever actually boiling—a process known as sublimation. When rapidly heated at high temperatures, bubbling does occur, but the compound quickly discolors, turning brown. This bubbling might be the result of pyrolytic decomposition rather than the actual boiling of salvinorin A. To vaporize salvinorin A, it need only be heated to just past its melting point, and with sufficient airflow, it will completely vaporize with no significant decomposition. Based on my own experiments using an adjustable thermocouple-controlled heat gun, I found that the ideal airstream temperature for vaporizing salvinorin A from dried leaves is approximately 277° C.5
Unfortunately, 277° C is well beyond the maximum temperature of the VaporGenie's advertised range of 107-190° C (225-375° F),6 and also above the Volcano's advertised maximum of 230° C (446°F).7 The Volcano runs hotter than some other electronic vaporizers, such as the Easy-Vap, which advertises a maximum temperature of only 204° C (400°F).
Nevertheless, a small informal poll of vaporizer users indicates that the Volcano is able to at least partially vaporize salvinorin A, with most users achieving effects by setting the unit to its maximum temperature. It may be that the actual maximum temperature exceeds what the manufacturer advertises.
The commercial vaporizers most effective with Salvia divinorum are those that employ a variable temperature heat gun as the heat source. One example is the Steinel HG 3002, which has an LCD temperature control adjustable in 10° F increments (120-1100 °F). Such heat guns allow the appropriate vaporization temperature for salvinorin A to be selected.
Two important safety notes: Because it can be easier to obtain strong effects when vaporizing instead of burning, extra care must be taken
when selecting and measuring doses. And, Siebert cautions that inhaling hot air can be irritating and potentially damaging to the lungs.5 Vapor produced by a heat gun needs to be cooled by running it through a water pipe or cooling chamber before inhalation.
The failure of most commercial cannabis vaporizers to successfully vaporize salvinorin A was described to Erowid as a challenge by one lab considering human research into the effects of Salvia divinorum. After looking into this issue, it appears that this challenge could be overcome by using a variable temperature heat gun, although additional testing would be required to show that temperatures are consistent enough for research purposes.
- Chemic Laboratories, Inc. "Evaluation of VolcanoŽ Vaporizer for the Efficient Emission of THC, CBD, CBN and the Significant Reduction and/or Elimination of Polynuclear-Aromatic (PNA) Analytes Resultant of Pyrolysis". Apr 2003.
- O'Neil MJ, Heckelman PE, Koch CB, et al. The Merck Index: 14th Edition. Merck & Co. 2006.
- Ortega A, Blount JF, Manchand PD. "Salvinorin, A New trans-Neoclerodane Diterpene from Salvia divinorum (Labiatae)". J Chem Soc Perkin Trans I. 1982; 2505-8.
- Valdes LJ III, Hatfield GM, Paul AG, et al. "Divinorin A, a Psychotropic Terpenoid, and Divinorin B from the Hallucinogenic Mexican Mint, Salvia divinorum". J Org Chem. 1984;49:4716.
- Siebert DJ. Personal communication. 2009.
- VaporGenie.com. "How does the VaporGenie Provide Vaporization?" Accessed Apr 22, 2009; VaporGenie.com.
- TheVolcanoVaporizer.com. "Volcano Classic Vaporizer vs. Volcano Digit Vaporizer". Accessed Apr 22, 2009; TheVolcanoVaporizer.com/compare-digital-classic.php.