The psychoactive constituent of cannabis, THC & CBD, are the most well known cannabinoids. However, in the plant, THC & CBD are actually produced a a non-psychoactive acid analog known as THCA or CBDA (acid cannabinoids), respectively. This is important because cannabinolic acids can be more than 20-fold more abundant than the neutral forms in fresh plant material. Although not psychoactive, THCA is an effective topical applicant that acts as an antibacterial and anti-inflammatory agent. Other acidic cannabinoids, including THCA, CBDA, and CBGA, are converted to the neutral form upon heating (> 105 oC). For example, THCA is converted to THC by flame or baking plant material in the oven. During the heating process the THCA molecule actually losses mass in the form of CO2.
Some people may be confused by the total THC or CBD contents in analytical reports.THE TOTAL THC CONTENT IS NOT EQUAL TO THE SUM OF THE THCA + THC. In fact it is always lower than the sum, because mass is lost when the cannabis smoked and the cannabinolic acids are converted to the neutral form. Some labs are reporting the sum of THCA and THC, but would mislead the audience with an artificially high result if the target product was distillate or isolate. Taking into account the stoichiometric loss of carbon dioxide is the most accurate way to report the total THC or CBD content, because it is the maximum amount of THC or CBD you could obtain if all THCA were converted to THC.