[5] A study found THCA and unheated Cannabis sativa extracts exert immuno-modulating effect, not mediated by the cannabinoid CB1 and CB2 receptor coupled pathways like THC.

THCA was able to inhibit the tumor necrosis factor alpha (TNFα) levels in U937 macrophages and peripheral blood macrophages, an inhibition that persisted over a longer period of time, whereas after prolonged exposure time THC and heated extract tend to induce the TNFα level.

However, all fractions of C. sativa at a certain combination of concentrations show a significant increased cytotoxic activity and suppress COX-2 and MMP9 gene expression in both cell culture and colon tissue, suggest the anti-inflammatory activity of Cannabis extracts on colon epithelial cells derives from a fraction of the extract that contains THCA, and is mediated, at least partially, via GPR55 receptor.

[9] Although the decarboxylation of THCA to THC was assumed to be complete, which means that no THCA should be detectable in urine and blood serum of cannabis consumers, it is found in the urine and blood serum samples collected from police controls of drivers, suspected for driving under the influence of drugs (DUID).

[14] Hemp derived THCA is prevalent and explicitly unscheduled under the CSA's definition that legalizes all cannabis with less than 0.3% delta-9 tetrahydrocannabinol concentration.

Thus, any laboratory analysis of THCA using any technique involving significant heat will generate THC in the handling and analytical process.

Further, both the Farm Bill and the USDA specify that analytical testing of samples for total THC must use "post-decarboxylation or other similarly reliable methods".

[28][29] Tennessee is unique in that THCa is explicitly listed as an allowed hemp-derived cannabinoid,[30] and defense attorneys have successfully had prosecutions overturned due to post-decarboxylation testing of post-harvest plant material.