Teens who used a concentrated form of marijuana — sometimes called dabs, wax, shatter or crumble — are more likely to also use other drugs than kids who avoid marijuana, a new study suggests.

Marijuana concentrate can come in multiple forms, including oils and butter-like compounds, and can contain very high levels of THC, the psychoactive compound in cannabis. It’s often ingested using a vaping device and doesn’t smell like traditional pot.

In the study, published Monday in the journal Pediatrics, researchers surveyed almost 50,000 adolescents in Arizona. The researchers found that among teens who used any form of cannabis, 72 percent had experience with the more potent products.

Those findings should serve as an alert to parents who may not even know their kids are vaping, said the study’s lead author, Madeline Meier, an assistant professor of psychology at Arizona State University.

“I don’t know that parents know about this stuff,” Meier said. “If I weren’t a marijuana researcher, I don’t know if I saw [a vape with marijuana] that I would know what it was. Parents should educate themselves about what these forms of cannabis look like.”

To get a better sense of teen drug use, Meier and her colleagues surveyed 47,142 students in eighth, 10th and 12th grades from 245 schools across Arizona in 2018. The students were asked whether they’d ever used marijuana or marijuana concentrate, as well as whether they had used either in the past month. They were also asked about other drug use, peer substance use and whether they thought cannabis was safe.

Some questions on the survey were designed to reveal whether teens were rebellious, engaged in risky behaviors or doing poorly academically.

Overall, the researchers found that 33 percent of the teens had tried some form of pot and 24 percent said they had used concentrated forms. The likelihood of a student using cannabis rose with age: 20 percent of the eighth graders said they’d used the drug, compared to 35 percent of the 10th graders and 46 percent of the 12th graders.

Similarly, 15 percent of the eighth graders, 25 percent of the 10th graders and 33 percent of 12th graders said they had used cannabis concentrates. Concentrate users had the highest rates of having tried other drugs.

Meier is most concerned about the future of kids who use these concentrated forms of pot. Studies in adults have shown that concentrates may raise the risk of addiction, thinking and memory problems and psychosis, she said.

The new study comes at a time when the use of e-cigarettes and other vaporizers in teens has grown explosively, noted Dr. Sheryl Ryan, a professor in the department of pediatrics and chief of adolescent medicine at Penn State.

“Between 2011 and 2018, the rates of vaporizer (including e-cigarette) use by high school students increased from 1.5 percent to 20.8 percent,” Ryan wrote in an editorial published alongside the new study. It is those vaporizers and e-cigarettes that allow teens and others to use the highly concentrated forms of cannabis.

While some might conclude that the new findings mean that cannabis use is leading to other drugs, it’s more likely that cannabis use is simply a marker for the teens who are more likely to be drawn to drugs and other risk, said Ryan Vandrey, an associate professor in the department of psychiatry and behavioral sciences at Johns Hopkins University.

“Use of concentrates might be a predictor of more intensive cannabis use and the propensity to try more dangerous drugs,” Vandrey said.

The findings “are very concerning,” said Dr. Abigail Schlesinger, chief of the behavioral science division of the UPMC Children’s Hospital of Pittsburgh.

“Parents need to know about the risks,” Schlesinger said. “This is not your grandparents’ cannabis. It’s more concentrated. And there’s a lot of reason to believe that in the adolescent years, it alters brain development.”

Schlesinger echoed Meier’s call for parents to have some serious talks with their teens.

“Parents need to be clear that they don’t support cannabis use,” she said. “Because if we don’t give a clear message, then teens can take it as a tacit statement that it’s OK. That doesn’t mean you say they will be expelled from the family if they try something. But we need to tell them that if they do these things, they may not reach their full potential.”

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