Delta-8 tetrahydrocannabinol (d8-THC) or commonly known as “D8” or “Delta-8” is a popular cannabinoid in CBD markets and smoke shops because of its intoxicating properties and ambiguous legality in certain states. This article aims to clarify what Delta-8 is, its effects, and why its legality is vague.
WHAT IS DELTA-8?
Delta-8 THC is one of hundreds of cannabinoids found naturally in cannabis; however, it appears in such trace amounts that most, if not all, delta-8 products on the shelves are chemically synthesized from CBD isolate or THC distillate. This synthetic ingredient is then made into various consumer products such as vape oils, tinctures, and edibles.
Delta-8 THC is an isomer of delta-9 THC, the more commonly known version of THC that is naturally found in potent amounts in the cannabis plant. Being an isomer means that delta-8 has the exact same chemical formula of delta-9 (C₂₁H₃₀O₂) but in a slightly different configuration . The nomenclature, or naming of delta-8, refers to the double bond in the ring being on the 8th carbon versus the 9th carbon for delta-9 according to the dibenzopyran numbering convention , as highlighted in figure 1 below. The position of the highlighted double bond is what gives delta-8 its name as well as its effects on the body slightly differing from that of delta-9.
Figure 1. Structural differences between d8-THC and d9-THC, and the dibenzopyran numbering for THC-type cannabinoids is shown in blue text.
WHAT ARE THE EFFECTS OF DELTA-8?
Delta-8 interacts with the endocannabinoid system  which is responsible for maintaining homeostasis  in the body. All cannabinoids interact with this system in different ways, mainly through the CB1 receptors in the central nervous system and CB2 receptors in the peripheral nervous system. Whereas CBD might bind with just one of these receptors, THC in general binds to both the CB1 and CB2 receptors in the body, making it have a stronger effect on the body. While delta-9 binds to the receptors a certain way, that double bond shift on the delta-8 structure allows it to bind to the receptors differently, which in turn, causes it to have different effects on the body. For example, Delta-8 is known for having a less potent effect on the user compared to delta-9 , meaning that users still experience intoxicating effects, but the effects may be more mild than with the use of d9-THC.
IS DELTA-8 LEGAL?
Hemp and hemp-derived products are legal under the vague language of the 2018 Farm Bill, where hemp is defined explicitly as cannabis having less than 0.3% delta-9 THC on a dry weight basis . Under this definition of hemp, if a delta-8 product contains less than 0.3% delta-9, it is federally legal. However, delta 8-THC and other analogues of d9-THC fall into an ambiguous category of legality because while it is derived from hemp feedstock, they are also analogues of a controlled substance according to Title 21 U.S.C Sec 813 . So, there is conflict between the intent of the 2018 Farm Bill and other federal laws around controlled substances. Even though d8-THC has similar intoxicating effects as d9-THC and is listed as a controlled substance by the DEA, the 2018 farm bill has been interpreted by many as having the congressional intent to allow d8-THC and other synthetic THC analogues with intoxicating potential. Some states have taken steps to restrict or outright ban delta-8 and other synthetic cannabinoids derived from hemp. Currently, delta-8 has been restricted or banned in 18 states in the US .
THE FUTURE OF DELTA-8
Even with the ambiguity surrounding hemp derived analogs of THC and specific language restricting d8-THC products in many hemp markets, producers continue to question the intent of state and federal lawmakers with respect to analogs of d9-THC. Analogues of d9-THC are continuously being developed and marketed as legal alternatives to the naturally produced phytocannabinoid delta 9-THC. Predicting where all of this is going is difficult in the midst of two legal cannabis markets, hemp and marijuana. Perhaps the best solution is to consolidate the industry around federally legal cannabis and some of these “creative” legal workarounds will naturally go away with market demand.
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