Researchers say the practice of “dabbing” marijuana may produce cancer-causing chemicals.
How much do you know about “dabbing”?
The latest trend in marijuana consumption, researchers now say, produces carcinogenic substances.
Dabbing uses highly potent marijuana concentrates that are vaporized on a special dabbing rig, similar to a glass water pipe.
However, unlike a traditional pipe, dabbing rigs use a small heated surface, called a nail, typically made of glass, metal, or ceramic.
The user applies the marijuana concentrate, or dab, to the nail, releasing vapors that they inhale.
Marijuana concentrates are often extracted using butane, resulting in a final product called butane hash oil (BHO).
BHO goes by a variety of names, typically based on its consistency: wax, oil, shatter, and butter (or budder).
It’s also viewed by some as being easier on the lungs than smoking marijuana.
This form of consumption is new, only becoming popular in the past few years.
On account of this, scientific data on BHO consumption is limited.
New research from Portland State University has now identified that dabbing vapor contains known carcinogenic substances, including methacrolein and
More specifically, scientists identified that terpenes, a class of organic compounds found in marijuana, are responsible for the resulting carcinogens when smoked or vaporized.
Terpenes commonly occur in plant resins. They give marijuana plants their wide variety of aromas and fragrances.
Terpenes are used in essential oils and cosmetics, and serve as flavoring additives for electronic cigarette and vaporizer products.
“Terpenes are believed by many to be harmless flavorants because they are natural products,” Robert Strongin, a study author and professor of organic chemistry at Portland State, told Healthline. “When heated as part of a cannabis concentrate formulation via certain methods of dabbing, they can degrade to produce toxins.”
While the discovery of the relationship between terpenes and carcinogens may be a new development, others say that finding benzene and other toxic substances in BHO should be expected.
“It has long been known that the combustion of marijuana (or tobacco) produces benzene, acrolein, and scores of other noxious compounds,” said Dale Gieringer, PhD, director of the California National Organization for the Reformation of Marijuana Laws (NORML).
“In short, some of the toxins in regular smoked marijuana may also be produced by dabbing,” he told Healthline.
Studies exist comparing the carcinogenic effects of
Gieringer notes that like with tobacco, there are differences in composition between marijuana smoke and vapor.
Marijuana that’s smoked contains cellulose and other carbon compounds not found in marijuana concentrates.
“Therefore, one might reasonably posit that smoking poses greater hazards than dabbing,” he said.
Arguments for the safety of vaporizers and e-cigarettes often bring up vaporization versus combustion.
Vaporization occurs at lower temperatures than combustion, resulting in the formation of fewer toxic compounds when inhaled.
However, dabbing presents a problem in that there must be proper temperature control of the nail to vaporize the BHO and not burn it.
Appropriate vaporizing temperature can vary, depending on the makeup of the BHO and the user’s preference, but it’s typically around 572˚F to 662˚F (300˚C to 350˚C), according to the researchers.
Uncontrolled heating can result in the temperature of the nail being well above that recommended range.
While some electronic dabbing rigs do exist, the more common method is to use a culinary torch to heat the nail, which results in inconsistent and imprecise temperatures when dabbing.
Controlling temperature is “critical” to limiting exposure to carcinogens, said Strongin.
“Hotter temperatures afford more toxins,” he said. “This is what our work has shown so far. Using a torch to heat the nail so far appears to produce the most toxins from terpenes.”
Gieringer is also keenly aware of the detrimental effects of dabbing at high temperatures.
“The essential problem here is combustion, which breaks down terpenes and other compounds into other, potentially toxic compounds,” he said.
“Such problems may be avoided by the use of vaporizers, which don’t attain the high temperatures of combustion that cause these chemical changes.”
Dabbing at lower temperatures will result in a vapor with significantly less carcinogens.
“We have no evidence so far of finding toxins from terpenes at lower temps. The toxin levels decrease with lower temp,” said Strongin.