Study links cancerous toxins to cannabis extract

September 27, 2017, Portland State University

Researchers at Portland State University found benzene and other potentially cancer-causing chemicals in the vapor produced by butane hash oil, a cannabis extract.

Their study raises about dabbing, or vaporizing hash oil - a practice that is growing in popularity, especially in that have legalized medical or recreational marijuana.

Dabbing is already controversial. The practice consists of placing a small amount of cannabis extract—a dab—on a heated surface and inhaling the resulting vapor. The practice has raised concerns because it produces extremely high levels of cannabinoids—the active ingredients in marijuana.

The process of making hash oil also is dangerous because it uses highly flammable and potentially explosive butane as a solvent to extract active ingredients from marijuana leaves and flowers. In July, two people in Portland, OR, died in an explosion and fire at a home where butane hash oil was being manufactured.

"Given the widespread legalization of marijuana in the USA, it is imperative to study the full toxicology of its consumption to guide future policy," said Rob Strongin, a Portland State professor who led the study. "The results of these studies clearly indicate that dabbing, while considered a form of vaporization, may in fact deliver significant amounts of toxins."

Strongin and his team analyzed the chemical profile of terpenes - the fragrant oils in and other plants - by vaporizing them in much the same way as a user would vaporize hash oil.

Terpenes are also used in e-cigarette liquids. Previous experiments by Strongin and his colleagues at Portland State found toxic chemicals in e-cigarette vapor when the devices were used at high temperature settings.

The dabbing experiments produced benzene - a known carcinogen—at levels many times higher than the ambient air, Strongin said. It also produced high levels of methacrolein, a similar to acrolein, another carcinogen.

Their findings were published in the Sept. 22 issue of ACS Omega, a journal of the American Chemical Society.

Explore further: Concern with potential rise in super-potent cannabis concentrates

More information: Jiries Meehan-Atrash et al. Toxicant Formation in Dabbing: The Terpene Story, ACS Omega (2017). DOI: 10.1021/acsomega.7b01130

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4.2 / 5 (5) Sep 27, 2017
Remove regulations against Cannabis and the production costs will drop to about the same as broccoli making the safer rosin, water, and dry sift hashes affordable for everyone. Not many gangs buying guns with broccoli money. Of course private for profit prisons would be unnecessary. Then we could start using it for some of the 50,000 industrial applications outlined in Popular Mechanics before the industrialists monopolized our economy with this state sanctioned prohibition that went against all scientific fact then and now. You may say I'm a dreamer, but I'm not the only one.
2.6 / 5 (5) Sep 27, 2017
making the safer rosin, water, and dry sift hashes affordable for everyone.

It's less about cost and more about the fact that the users want a bigger faster high, so they need highly concentrated THC with little or no other components:

In dabbing, users inhale through a water pipe the vapor from "dabs" of waxy or solid marijuana concentrate. A piece of superheated metal or glass instantly vaporizes the dab, creating an intense high from a single inhalation.

Dabs, also known as butane hash oil, are created by stuffing marijuana trimmings into a glass, metal or plastic pipe, according to the U.S. Drug Enforcement Agency. Butane is forced into the pipe, and the flammable liquid extracts THC from the plant material.

The crystallized resins created by the process can have a THC concentration approaching 80 percent, the study authors said. THC, or tetrahydrocannabinol, is the chemical compound in marijuana that causes intoxication.

2.1 / 5 (7) Sep 27, 2017
Also, with 80% THC the effects of the drug are no longer the same silly hungry stoner stuff:


Some like the "alert high", kinda like how some people are adrenalin junkies, I guess. Problem is, potent THC also makes you psychotic and paranoid, so the highly concentrated varieties are more like madness in a bottle.
5 / 5 (3) Sep 27, 2017
Eikka: Wow, "madness in a bottle." You must mean Scotch whisky, which has been known to provoke people to acts of spontaneous violence and stupidity (like drunk driving).

Pot just makes its abusers sleepy. Concentrates likewise. The "alert high" has nothing to do with adrenaline; it's like a strong cup of coffee. But the sad truth is, the effects of mood altering drugs attenuate --- driving users to higher dosing. Which doesn't work for long. The only way to get "high" after a user reaches saturation is --- to stop getting high. Take a week off, and the stuff delivers euphoria again, but then the cycle must be repeated.

Note to copy editor: The headline is misleading since it suggests the toxins are inherent in the extract itself. You have to go to the story to learn the toxins are due to poor manufacturing processes. In fact, the anti-tumoral properties of THC may reduce or eliminate the cancer risk, as shown in UCLA's ground-breaking smoking study.

1.7 / 5 (6) Sep 27, 2017
Eikka: Wow, "madness in a bottle." You must mean Scotch whisky, which has been known to provoke people to acts of spontaneous violence and stupidity (like drunk driving).

Tu-quoque, eh?

The staple comeback of people who try to defend something bad: "yours is equally bad".

My problem with pot is that I've watched people literally smoke themselves retarded, and the stronger the stuff they smoked the more argumentative, delusional, shut in and weird they became, to the point of starting fights with people because they were constantly imagining stuff that wasn't done or said. Everything just turns to drama.

You have to go to the story to learn the toxins are due to poor manufacturing processes.

Actually, due to the way its quickly vaporized on a hot surface, which causes chemical changes in the oil similiar to how burned cooking grease turns carsinogenic.
5 / 5 (2) Sep 27, 2017

It's less about cost and more about the fact that the users want a bigger faster high, so they need highly concentrated THC with little or no other components:

No, Eikka,

As with virtually every other industry, it is almost ONLY about cost.
In this case, the butane extraction is the down-and-dirty super cheap way to get the job done.
This, then, is an outstanding exasmple of the most common failure of capitalism, and not--as you would lead us to believe-- a study in ill-conceived policy.

There are other methods to achieve the same end which avoid this dangerous side effect, which --at this point, at least-- remains purely anecdotal, since these researchers didn't use the actual compounds or processes involved, which is another very salient issue which you failed to address in your anti-cannabis screed.

1 / 5 (2) Sep 27, 2017
Well derp. Cannabis is a hydrocarbon factory
5 / 5 (2) Sep 27, 2017
Misleading article. Should be "Study links cancerous toxins to high-temp terpene vaporization"

I don't think many of you non smokers are fully aware of why pot smokers prefer dab.

Over time, we end up smoking less, it isn't chasing a high, it's running away from vegetative matter and the couch lock type highs it along with low temp burns produce.

I love all these people commenting as though they fully understand the situation when they've never smoked in their life.

There ARE going to be people smoking more and more chasing a high, and these are the types of people who make people think marijuana is a gateway drug. But how is this any different from alcohol? How many people with alcohol addictions eventually turned to heroin?

Anyone smoking in moderation, dabs for the same reason. It's clean, and for the quantity smoked it lasts longer.
not rated yet Oct 03, 2017
You're talking about hash oil that people make with primitive setups in their kitchens, not hash oil produce in laboratory with other kinds of non-harmful solvents. That homemade hash oil is just like any other street drug. It's buyer beware because they make the stuff with gasoline if the have to. So, if you are buying from reputable source, it shouldn't have benzene in it.

There have been a number of fires related to the manufacture of homemade hash oil. Numerous people have been badly burned because they boil off the solvent, sometimes on an open flame and it is highly flammable. But, it's done because it creates a valuable commodity from the worthless stems. So, it's not going to stop until the price of hash oil is to cheap to make it worthwhile.
1 / 5 (1) Oct 31, 2017
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