Marijuana concentrate products, which  often are lumped  together with edibles, dabs, hash oil and many cannabinoid (CBD) liquids, are one of the hottest products in pot shops. By some estimates, they account for 30 to 60 percent of sales at dispensaries. They're often used in portable vaporizers that pair discretion with a level of potency not always experienced with traditional cannabis flowers.

Mostly produced by dousing weed with butane, concentrates have earned a bad name as a result of countless amateur lab explosions. At the same time, investor-backed producers are entering the market with safely produced concentrates and even “solvent-free” products. But as many industry leaders have argued against banning or heavily regulating concentrates, a new study says using this form of cannabis could be seriously bad for your health.

“Toxicant Formation in Dabbing: The Terpene Story” from researchers at Portland State University was recently published in the American Chemical Society's ACS Omega journal. A summary notes that concentrates “are playing a central role in the expansion of the medical and recreational use of cannabis.”

But authors warn that burning dabs, wax and other forms of concentrates in bongs, as is often done, exposes users to carcinogenic terpenes, namely methacrolein and benzene. Dabbing can produce benzene at levels “many times higher than the ambient air,” according to a statement. High levels of methacrolein were also produced in the lab, researchers said.

“The results of these studies clearly indicate that dabbing, while considered a form of vaporization, may in fact deliver significant amounts of toxins,” lead study author Rob Strongin, a Portland State organic chemistry professor, said in a statement.

The research suggests that burning something and inhaling it has generally been known to be carcinogenic — potentially cancerous. Terpenes have even been found in some e-cigarette liquids, researchers say.

“This happens in anything that burns,” says Dale Gieringer, coordinator of California NORML and a published marijuana researcher in his own right. “It happens in cigarettes and it happens in pot flowers.”

He said the dangers aren't something that could be addressed through regulation of the butane extract process, although newer, solvent-free processes might produce safer products because “they often they take terpenes out.” Otherwise, Gieringer says, the study is “not surprising.”

The group Citizens Against Legalizing Marijuana used the Oregon research to bolster its argument that California has gone too far with recreational pot legalization. Retail sales are scheduled to begin in January under voter-approved Proposition 64.

“We should definitely ban concentrates,” says Scott Chipman, the organization's Southern California chair. “The gap between what people who are studying the harms know and what the public knows is worrying.”

LA Weekly