Jonathon Kelso/The New York Times/Redux
FILE -- Delta-8 cartridges in Decatur, Ga., Feb. 23, 2021.
CNN  — 

High school seniors’ use of delta-8, a cannabis compound that’s sometimes marketed as “light THC” or a legal alternative to weed, is “appreciable,” according to a new study, particularly in states that don’t have a legal weed option for adults.

Delta-8 THC, or delta-8 tetrahydrocannabinol, is one of more than 100 chemical compounds found in the cannabis sativa plant. It’s an isomer or chemical cousin of sorts to delta-9 THC, the molecule that creates a high when someone ingests cannabis. Delta-9 is the most abundant form of THC in weed and is responsible for most of the psychoactive effects. Delta-8 acts on the brain the same way but is less potent and has fewer legal restrictions.

Unlike with weed, there are no age restrictions for buying delta-8 in most states where the product is legal. Based on findings in the study, published Tuesday in the journal JAMA, the authors argue that the number of teens who have reported using delta-8 may be a “potential public health concern.”

“What we hadn’t known prior to this study was to what extent are these products reaching teens, which was a concern because they weren’t being comprehensively regulated,” said study author Dr. Adam Leventhal, executive director of the USC Institute for Addiction Science.

Delta-8 comes in many forms that may appeal to kids, like gummies, chocolate, cookies, vaping cartridges, sodas and even breakfast cereals. Delta-8 is also easily accessible since it is sold in convenience stores, gas stations and online, rather than only at age-restricted dispensaries.

For the new study, the researchers used data from the Monitoring the Future in-school survey conducted across the US between February and June 2023. The survey is an ongoing nationally representative assessment of adolescents’ behavior and attitudes about a variety of topics. Researchers first measured delta-8 use in 2023.

In the sample of 2,186 12th-grade students, 11.4% said they had used delta-8 THC in the past year, and even though weed is illegal for teens, 30.4% of the participants reported using it.

Of the 295 students who reported that had they used delta-8 in the previous year, 68.1% used it at least three times, 35.4% had used it at least 10 times, and nearly 17% used it at least 40 times. Close to 91% of the delta-8 users also reported using weed.

Delta-8 use was higher among teens in the South and the Midwest and in states where marijuana is not legal for adults, the study found.

White teens were more likely to use delta-8 and weed than those of any other race or ethnicity. Slightly more boys used weed and delta-8 than girls, according to the study.

“Eleven percent is a lot of people. That’s at least one or two students in every average-sized high school class who may be using delta-8. We don’t know enough about these drugs, but we see that they are already extremely accessible to teens, “ Dr. Nora Volkow, director of the National Institute on Drug Abuse, who was not involved in study, said in a statement. “Cannabis use in general has been associated with negative impacts on the adolescent brain, so we must pay attention to the kinds of cannabis products teens are using, educate young people about potential risks, and ensure that treatment for cannabis use disorder and adequate mental health care is provided to those who need it.”

Leventhal also said that 11% is a “very high” number.

“We weren’t expecting it to be that high, and it was concerning when we saw the data,” he said.

The study does have some limitations. The survey does not include teens in every state, and it surveys only those who are enrolled in school. Most of the participants were about 17 years old, so the study may not fully represent how many younger teens are using delta-8.

The authors say their research probably underestimates how many kids are using these drugs. There has been a general concern that the number of students using delta-8 has been growing, according to an editorial published Tuesday alongside this study.

“The unregulated proliferation of Δ8-THC represents a potential threat to the public’s health,” wrote Drs. Jennifer Whitehill, Kelly Dunn and Renee Johnson, who are scientists at the University of Massachusetts Amherst and Johns Hopkins University. “The trends in use patterns for Δ8-THC articulated by Harlow et al should serve as an important sentinel and mobilizing event; the next cannabinoid on the marketplace may not be so mild.”

Delta-8 use has been enough of a concern among some public health officials and politicians that it is banned in at least 17 states and “severely restricted” in seven more as of November, according to the National Cannabis Industry Association.

Scientists don’t fully understand what effects delta-8 may have on teens. There are no large medical studies to show exactly how it affects the body, particularly a young one that is still developing. Research on weed has found that it can negatively impact teens’ memory and attention as well as their ability to learn.

“Some of the concerns based on the underlying biology would be, of course, addiction, like what we see with marijuana, some of the neurodevelopmental changes that can happen because the adolescent brain is still forming and exposure to intoxicating substances can interfere with proper development of the brain pathways that support cognition and emotion regulation,” Leventhal said.

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The FDA regulates drug products with cannabis or cannabis-derived compounds like it does with other pharmaceutical and medical products, but it does not regulate delta-8, so it is also not completely clear what is in each individual product.

There are other indications that delta-8 use has been growing and causing some problems. Calls to America’s Poison Centers about delta-8 products spiked 82% from 2021 to 2022, the group said in a recent report, with 3,358 exposures managed in 2022. The calls fall into two categories: kids who have accidentally ingested the products and adults who had bad reactions.