Δ8-THC is a naturally occurring cannabinoid that has seen growing use in the form of concentrates, edibles, and tinctures over the past year due to its mild pharmacol. effects compared to Δ9-THC as well as its possible designation as a federally legal hemp product.Though Δ8-THC is naturally occurring, it is most commonly produced in bulk by conversion from CBD isolate through a p-toluenesulfonic acid-catalyzed reaction with various Lewis acids.This class of reactions often produces Δ8-THC as the primary component, but also produces other unwanted byproducts such as Δ9-THC and other isomeric cannabinoids.This work compares different chromatog. methods in conjunction with other techniques such as NMR spectroscopy to definitively identify isomers of Δ9-THC in these synthetic products and truly determine whether they meet the criteria for legal hemp (<0.3% Δ9-THC content).Here the authors show that GC-MS is the most effective technique in the typical anal. cannabis laboratory toolset to quantify the cannabinoid content of these products, while more common techniques for cannabis potency anal., such as HPLC, are inadequate to make a definitive presence/absence determination of Δ9-THC.