Phytocannabinoids are the molecules found in the cannabis plant. Endocannabinoids are the receptors that are activated by THC and other similar molecules. Molecules that activate these receptors are not naturally produced by the body. The saliva test picks up on the metabolites produced in the body after ingesting cannabis, typically THCa, the carboxylic acid derivative of THC. This is just a preliminary test, as there are other molecules that can produce a false positive for the THC saliva test. If the saliva test is positive for THC, a second confirmatory test must be performed in order to produce a conviction. The preliminary test is inexpensive and can be done very quickly. The confirmatory test is more expensive, more time consuming, and generally requires someone with a chemistry degree to perform. This is why the confirmatory test is not done first.

Phytocannabinoids are derived from plants while endocannabinoids are found internally in the body. And thank you for the feedback about the text, we will look into this!