Delta-8-tetrahydrocannabinol (delta-8-THC, Δ8-THC) is a psychoactivecannabinoid found in the Cannabis plant. It is an isomer of delta-9-tetrahydrocannabinol (delta-9-THC, Δ9-THC), the compound commonly known as THC. ∆8-THC is under preliminary research for its biological properties. Delta-8-THC has not been approved by the FDA thus far for public use and should not be used around children or pets. 
∆8-THC is moderately less potent than Δ9-THC. This essentially means that it has properties similar to those of ∆9-THC, although to a lesser degree per milligram of material consumed. Delta-8-THC and delta-9-THC both contain a double bond in their molecular chain, but the location is different. Delta-8-THC has the bond in the 8th carbon chain while delta-9 contains it in the 9th carbon chain.
A 2021 survey of 521 people who use delta-8-THC found that the most common self-reported effects were relaxation (71%), euphoria (68%), pain relief (55%), difficulty concentrating (81%), difficulties with short-term memory (80%), and alerted sense of time (74%).
The pharmacodynamic profile of ∆8-THC is similar to that of ∆9-THC. It is a partial agonist of CB1 and CB2cannabinoid receptors with about half the potency of ∆9-THC in most but not all measures of biological activity. ∆8-THC has been reported to have a Ki value of 44 ± 12 nM at the CB1 receptor and 44 ± 17 nM at the CB2 receptor. These values are higher than those typically reported for ∆9-THC (CB1 Ki = 40.7 nM) at the same receptors, indicating that ∆8-THC binds to cannabinoid receptors less efficiently than ∆9-THC.
∆8-THC is a tricyclic terpenoid. Although it has the same chemical formula as ∆9-THC, one of its carbon-carbon double bonds is located in a different position. This difference in structure increases the chemical stability of ∆8-THC relative to ∆9-THC, lengthening shelf life and allowing the compound to resist undergoing oxidation to cannabinol over time. Like other cannabinoids, ∆8-THC is very lipophilic (log P = 7.4). It is an extremely viscous, colorless oil at room temperature.
∆8-THC has a double bond (a) between the carbon atoms labeled 8 and 9. ∆9-THC has a double bond (a) between the carbon atoms labeled 9 and 10.
The ongoing controversy regarding the legal status of ∆8-THC in the U.S. (see below) is complicated by chemical nomenclature. According to a 2019 literature review published in Clinical Toxicology, the term "synthetic cannabinoid" typically refers to a full agonist of CB1 and CB2cannabinoid receptors. According to the review, "The psychoactive (and probably the toxic) effects of synthetic cannabinoid receptor agonists are likely due to their action as full receptor agonists and their greater potency at CB1 receptors." Because ∆8-THC and ∆9-THC are partial agonists of cannabinoid receptors, rather than full agonists, these compounds are less potent and less toxic than many synthetic cannabinoids. Although it has not been definitively proven if full agonism is the reason for toxicity as Delta-9-THC has been shown to act as a full CB1 agonist on specific CB1 receptors located in the hippocampus section of the brain. and the synthetic cannabinoid EG-018 acts as a partial agonist The classical cannabinoid dibenzopyran structure class of drugs which includes THC interact with a different spot inside of the CB1 receptor than synthetic cannabinoid compounds of unrelated chemical classes such as Naphthoylindoles do which may contribute to toxicity.
In 1937, Delta-9 THC was made illegal with the passage of the Marihuana Tax Act, which made cannabis illegal on a federal level. Over the course of the 1970s, 11 states decriminalized marijuana, with others reducing related penalties. In 1976, a parent’s movement started which influenced concerned emotions and questions, leading to the war on drugs in the 1980s. President Ronald Reagan re-enacted mandatory sentences for cannabis-related offenses.
The 2018 United States farm bill signed into law in December 2018 states that, "Any cannabis containing under 0.3% Delta-9 THC is classified as “hemp” and no longer a controlled substance.", ∆8-THC products partially synthesized from compliant sources (including industrial hemp and derivative cannabidiol extracts) have been sold by a range of digital vendors and a more limited array of brick and mortar retailers, including head shops. Ranging from bulk quantities of unrefined distillate to prepared edibles and atomizer cartridges suffused with cannabis-derived terpenes, they are usually marketed as federally legal alternatives to their ∆9-THC counterparts. However, the legal status of ∆8-THC at the federal level is in question with some believing that the Oct. 2020 DEA IFR addressing "synthetics" applied to Delta-8 and other hemp derivatives allowed by the Farm Bill. While most states have legalized ∆8-THC, a handful have not leading to confusion as to whether or not it should be legalized.
Beginning in late 2020, ∆8-THC began to attract the attention of many cannabis consumers throughout the United States. Thought of as an alternative to traditional cannabis use, especially in areas where marijuana is illegal, the news of ∆8-THC spread quickly via multiple media platforms which attracted a storm of social media attention. With ∆8-THC starting to attract the attention of people, it has made it easy for smoke shops and dispensaries to start carrying ∆8-THC infused edibles and atomizer cartridges for individuals to purchase.
Because marketing of ∆8-THC products does not require special licensing or, the fact that these products can be produced and marketed nationally instead of one state at a time, and have no more tax than an ordinary sales tax, if that, means that they are far cheaper than ∆9-THC products purchased in a cannabis dispensary. They can be sent through the mail; ∆9-THC products, still illegal at the federal level, can not. As of 2021, a sizeable new industry, including franchises, is being or has already been created.
As of early 2021, "Delta-8"/∆8-THC is one of the fastest growing segments of products derived from hemp. Delta-8-THC products have been sold in regulated recreational cannabis and medical cannabis industries within the United States for over one year.
Delta-8-THC products have been sold in regulated recreational Cannabis and medical Cannabis industries within the United States for over 2 years. Including California's regulated recreational Cannabis industry  and Pennsylvania's regulated medical Cannabis industry both with products containing Delta-8-THC at levels unnaturally higher than what the plant can produce suggesting chemical conversion.
Side effects, Risks, and Safety concerns
∆8-THC is typically synthesized from cannabidiol extracted from hemp as the natural quantities of Delta 8 found in hemp are low. The reaction often yields a mixture that contains other cannabinoids and unknown reaction by-products. As a result, most products sold as ∆8-THC are not actually pure ∆8-THC. Little is known about the identity and the health effects of the impurities.
The safety profile of regular, long-term delta-8-THC use is unknown. The FDA has reported 104 adverse event reports related to delta 8 THC, including one pediatric case with a coded outcome of "death". National poison control centers received 2,362 exposure cases of delta-8 THC products between January 1, 2021 (i.e., date that delta-8 THC product code was added to database), and February 28, 2022, 58% of these exposures involve adults.
When using ∆8-THC, there are some minor side effects that one may experience when using. When using, one may experience dry mouth, fatigue and red eyes.  ∆8-THC can be used in a variety of ways such as disposable vapes, edibles and atomizer cartridges. People that consume ∆8-THC edibles are more likely to experience severe side effects as compared to other methods of ingesting.  When ingesting, one may also experience the "munchies". This stimulates one's appetite and makes them eat food uncontrollably. One will consume large portions of food compared to what an average person would eat in a day.
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