A new study by the Medical Marijuana Research Institute in Tempe, Arizona tested marijuana oil thinning agents, which are mixed together in the production of vaporizer cartridges used for vaporizing marijuana oil.
Vaporization creates an inhalable aerosol by heating marijuana to a temperature at which the plant’s chemical compounds boil. Because the marijuana is not heated to the point of combustion, fewer carcinogens and irritants are produced. Compared with smoking, vaporization is associated with fewer respiratory issues in marijuana users, which some researchers suggest is a result of lower exposure to toxic substances.
Published in The Journal of Alternative and Complementary Medicine, the study analyzed four marijuana oil thinning agents – propylene glycol [PG], vegetable glycerin [VG], polyethylene glycol 400 [PEG 400], and medium chain triglycerides [MCT] – which were all heated to 230 degrees Celsius, the maximum temperature at which the plant’s chemical compounds vaporize but do not combust. The resulting vapors were then tested for formaldehyde, acetaldehyde, and acrolein.
The Institute stated: “Formaldehyde production from PEG 400 isolate was particularly high, with one inhalation accounting for 1.12 percent of the daily exposure limit, nearly the same exposure as smoking one cigarette. Because PG and PEG 400 are often mixed with cannabis oil, individuals who vaporize cannabis oil products may risk exposure to harmful formaldehyde levels.”
A large discrepancy was found between the two types of thinning agents: the natural agents (MCT and VG) and the petroleum-based agents (PEG 400 and PG). The study concluded that medium chain triglycerides (MCT) and vegetable glycerin (VG) are by far among the safest thinning agents available to individuals who vape marijuana oil.