The proliferation of products containing delta-8 tetrahydrocannabinol (THC) hasn’t exactly been a case of “hiding in plain sight,” but as the products have gained greater popularity in states where recreational marijuana is still illegal, disagreement abounds as to whether Congress intended hemp-derived THC products to be lawfully sold and used.

That disagreement is the basis of an Arkansas law, Act 629 of 2023, that has been challenged in federal court — and will be the subject of a hearing Wednesday in U.S. District Court in Little Rock.

The 2014 Farm Bill, signed by President Barack Obama, established the Hemp Research Pilot Program to allow for hemp cultivation for research purposes by higher education institutions or state departments of agriculture. The 2018 Farm Bill, signed by President Donald Trump, established the Domestic Hemp Production Program, which made hemp production eligible for federal crop insurance and reduced some of the legal risks associated with financing hemp production or processing by farm lenders.

The 2018 Farm Bill also removed hemp from the Controlled Substances Act’s statutory definition of marijuana and from oversight by the Drug Enforcement Administration. To be classified as hemp, cannabis must contain less than 0.3% delta-9 THC by volume of dry weight. Cannabis containing concentrations of delta-9 THC above 0.3% is classified as marijuana and is illegal under federal law.

In the wake of that move some in the cannabis industry began experimenting with ways to extract THC isomers from cannabidiol (CBD), a non-intoxicating compound which is found in abundance in hemp. One of those compounds, delta-8 THC, offers a less-potent alternative to delta-9 THC, which is the primary psychoactive compound found in marijuana.

In the 2018 Farm Bill, Congress expressly excluded hemp, which it defined as the plant species cannabis sativa L. — “and any part of that plant, including the seeds thereof and all derivatives, extracts, cannabinoids, isomers, acids, salts, and salts of isomers, whether growing or not, with a total delta-9 tetrahydrocannabinol concentration of not more than 0.3 percent on a dry weight basis” — from the federal Controlled Substances Act, clearing the way for an expansion of industrial products derived from the plant including rope, paper and clothing.

However, that resulted in a glut of CBD extracted from U.S.-grown hemp and caused the price of CBD to plummet, requiring producers to find other ways to keep revenue up, according to the American Chemical Society.

“Looking for ways to turn the glut of CBD into something profitable,” said a 2021 Chemical & Engineering News article, “the industry got creative and started experimenting with ways to convert CBD into delta-8-THC. The resulting products target consumers who are looking to relieve stress and anxiety, especially those who don’t want to use traditional cannabis products or those who live in places where cannabis products are not legally available.”

Producers of the converted THC isomers infused them into products such as gummies, vape pens and oils, primarily marketed to stores that specialize in selling non-intoxicating CBD products. Some use delta-8 recreationally while others use it as a milder alternative to medical marijuana.

The emergence of intoxicating cannabinoids like delta-8 THC has prompted concern among lawmakers in states across the country leading to a patchwork of regulations for the products as well as — in some states, including Arkansas — outright bans. Arkansas’ new law prohibiting delta-8 also outlaws similar substances found in hemp, including delta-9, delta-6a, delta-10a and delta-10, reclassifying them as a Schedule VI drug in Arkansas, the same class of drug as marijuana.

That law — Act 629 of 2023 — has been challenged in federal court and is the subject of a hearing on Wednesday before U.S. District Judge Billy Roy Wilson to determine whether the law will be blocked temporarily while the lawsuit moves through the court system or if the lawsuit will be dismissed.

Variants from THC sourced from hemp are converted with heat or chemical catalysts from legal hemp-derived CBD. According to Dale Gieringer — director of the California Drug Policy Forum and co-author of Marijuana Medical Handbook: Practical Guide to Therapeutic Uses of Marijuana — delta-8 THC is an isomer, or minor chemical variant, of delta-9 THC that occurs only at minuscule levels in natural cannabis. High levels of delta-8 THC are produced artificially by chemically converting CBD or delta-9 THC through a process known as isomerization.

According to the 2018 federal Farm Bill, all hemp “derivatives, extracts, cannabinoids, isomers, acids, salts, and salts of isomers” are federally legal as long as they contain no more than 0.3% delta-9 THC. Last year, the 9th Circuit Court of Appeals in San Francisco ruled that the loophole allowing for the development of delta-8 along with other hemp-derived cannabinoids was legal.

In its ruling, the 9th Circuit panel said, “the plain and unambiguous text of the Farm Act compels the conclusion that the delta-8 THC products before us are lawful.”

The 9th Circuit also held that the method of manufacture of hemp-derived THC products does not determine whether the product is “synthetic” in nature, only that it is not produced from a source other than industrial hemp as defined in the 2018 Farm Bill.

“Regardless of the wisdom of legalizing delta-8 THC products, this court will not substitute its own policy judgment for that of Congress,” wrote Judge D. Michael Fisher in the court’s unanimous opinion. “If … Congress inadvertently created a loophole legalizing vaping products containing delta-8 THC, then it is for Congress to fix its mistake.”

The Food and Drug Administration, citing health and safety concerns, has thus far declined to promulgate rules for the production and sale of hemp-derived CBD or THC products intended for human consumption. Given that lack of regulatory guidance and the growing popularity of products containing hemp-derived cannabinoids, many anticipate increasing state and federal regulation of hemp-derived cannabinoids, which could in turn have a significant impact on companies manufacturing and selling hemp-derived products.

One possible change being discussed in talks over the 2023 Farm Bill is an increase of allowable delta-9 THC content in hemp to a maximum of 1% from the current 0.3% threshold. Patrick Creamer, communications director for the Republican members of the Senate Committee on Agriculture, Nutrition and Forestry — of which Sen. John Boozman of Arkansas is the ranking member — confirmed Friday that discussions regarding possible changes to the maximum THC content allowable in hemp have been ongoing with that possible increase to a 1% threshold being part of those discussions. Creamer said that has been among many issues under discussion as the committee works to finalize the bill.

According to CBDThinker — which bills itself as “a science-based resource for everything related to cannabidiol (CBD) and other hemp-derived cannabinoid products” — as of Aug. 13, delta-8 is banned in 18 states, including Arkansas; legal in 25 states; and regulated like recreational marijuana in three states, and in an additional four states the status of delta-8 is murky.

As for marijuana itself, despite being legal for medicinal use in 38 states and the District of Columbia and legal for recreational use in 21 of those states and the District of Columbia, the plant remains illegal under federal law.

Information for this article was contributed by Alex Thomas with the Arkansas Democrat-Gazette Washington D.C. Bureau and Neal Earley of the Arkansas Democrat-Gazette.