Sourcing CBD: Marijuana, Industrial Hemp & the Vagaries of Federal Law

cbd oil legal
By on March 28, 2016

What are the best plants for extracting and making high quality CBD-rich oil? Marijuana, industrial hemp, both?

Let’s cut through the legal mumbo jumbo, the obfuscating nomenclature, and the marketing hype and let’s look at what’s really out there for sourcing CBD-rich oil.

In the cannabis world there are two types of plants, broadly categorized—hemp plants and drug plants. Hemp plants include plants grown for fiber and plants grown for seed oil. Drug plants include euphoric THC-rich plants and non-euphoric CBD-rich plants.

The key difference between hemp plants and drug plants is resin content. Most hemp plants are low-resin plants. Drug plants are high-resin plants.

Industrial hemp varieties are typically a low-resin agricultural crop, grown from pedigree seed, with about one hundred tall, skinny plants per square meter, machine harvested and manufactured into a multitude of products.

Drug plants are a high-resin horticultural crop, typically grown from asexually reproduced clones, 1 to 2 plants per square meter, hand-harvested, dried, trimmed and cured.

Resin Rules

Federal law originally defined marihuana in terms of resin content. Resin was mentioned no less than three times in the definition of “marihuana” encoded in the 1970 Controlled Substances Act, which was lifted word-for-word from the 1937 Marihuana Tax Act:

The term “marihuana” means all parts of the plant Cannabis sativa L. [sic], whether growing or not; the seeds thereof; the resin extracted from any part of such plant; and every compound, manufacture, salt, derivative, mixture, or preparation of such plant, its seeds or resin. Such term does not include the mature stalks of such plant, fiber produced from such stalks, oil or cake made from the seeds of such plant, any other compound, manufacture, salt, derivative, mixture, or preparation of such mature stalks (except the resin extracted therefrom), fiber, oil or cake, or the sterilized seed of such plant which is incapable of germination.

In plain English, this says that certain parts of the plant (“mature stalk” and “sterilized seed”) are exempt from the legal definition of marijuana. But not included in this exemption are the flowers, the leaves, and the sticky resin wherever it is found on the plant.

Federal law was unequivocal on this point: the resin from any part of the marijuana plant, or any “preparation” made from the resin, is strictly out of bounds. Fiber produced from hemp stalk and oil pressed from hempseed got a legal pass, but not the resin. The Feds didn’t want anyone messing with the resin.

As far as medicinal and recreational cannabis goes, the resin is where the action is. The resin contains THC (tetrahydrocannabinol) and CBD (cannabidiol), along with dozens of other secondary plant metabolites (primarily other cannabinoids and terpenoids) that augment human brain chemistry and alleviate physiological and psychological distress.

The sticky, gooey cannabis resin is sequestered within the heads of tiny, mushroom-shaped trichomes, found mainly on the plant’s odiferous female flowers (the buds) and to a lesser extent on the leaves. There are also the measly sessile trichomes, which dot the stalk of the hemp plant, but these contain hardly any resin. Non-glandular hairs shaped like tiny inverted commas also cover the plant’s surface.

Among low resin hemp varietals, dioecious oilseed plants (for making nutritional oil, body care and industrial products) have a higher density of trichomes than monoecious fiber hemp plants. Hempseed oil is not the same as CBD-rich oil extracted from the flowers and leaves of the plant. Oil pressed from hempseed contains no CBD, no THC, no plant cannabinoids to speak of, but it’s excellent for making varnish, paint, soap, nutraceuticals, and much more.

Kentucky hemp


Hemp or marijuana in Kentucky


Outdoor medical marijuana grow


The THC Trap

Right from the start, the Feds assumed that resin content was the key factor that distinguished marijuana from industrial hemp. Today, however, federal law includes a recently added caveat that officially characterizes industrial hemp as having no more than 0.3 percent THC by dry weight. Such a tiny amount of THC would not have a euphoric (or dysphoric) effect.

Where did the 0.3 percent THC figure come from? It stems from a 1976 taxonomic report by Canadian plant scientists Ernest Small and Arthur Cronquist, who never intended for 0.3 percent THC to function as a legal demarcation between hemp and other forms of cannabis.

But that’s exactly what has happened.

The Drug Enforcement Administration opened this can of worms when it tried to ban hemp food products, including nutrient-dense hempseed oil, even though these products are about as psychoactive as a baked potato. On October 9, 2001, the DEA published an “Interpretative Rule,” which stated that “any product that contains any amount of THC is a schedule I controlled substance.” But this ungainly attempt to destroy hemp food commerce in America would falter thanks to the efforts of the Hemp Industries Association (HIA), which engaged in protracted litigation against the DEA. The HIA scored a major victory in February 2004 when the Ninth Circuit Court of Appeals rejected the DEA’s hemp food ban on substantive grounds.

The legal status of CBD was not affected by this court decision. The Controlled Substances Act remained the law of the land. Yet CBD hemp oil purveyors would often cite the Feb 2004 court ruling as the basis for asserting that their products are “legal in all 50 states.” This court decision, however, never mentions CBD, and the HIA and Joe Sandler, the HIA’s lead attorney in the case, maintain that this ruling did not legalize CBD.

The Farm Bill

Nor did the 2004 court decision (HIA, et al. v DEA, et al.) mention a specific percentage of THC as a determinative factor regarding what’s permissible in industrial hemp. It wasn’t until ten years later with the passage of the Federal Farm Bill, otherwise known as the Agricultural Act of 2014, that the ‘0.3 percent THC or less’ qualification for hemp was enshrined into federal law.

Section 7606 of the Agricultural Act defined “industrial hemp” for the first time in U.S. history and distinguished it from marijuana. Cannabis was hemp, not marijuana, as long as no part of the plant (including the leaves and flowers) exceeded a THC concentration of “more than 0.3 percent on a dry weight basis.”

Resin was not mentioned in Section 7606 of the Farm Bill, which also carved out a legal exception for growing industrial hemp in the United States under the auspices of state-approved pilot research programs. This loophole opened up huge opportunities for industrial hemp advocates and entrepreneurs.

Whereas previously only products made from hemp grown abroad could be marketed in the United States, for the first time in many years American farmers were allowed to cultivate industrial hemp on domestic soil, albeit on a provisional basis. But only states that legalized industrial hemp farming could opt into this federally sanctioned agricultural experiment. Growing industrial hemp outside the parameters of state-sanctioned pilot research is still forbidden under federal law.

Bluegrass CBD

Kentucky, an early 19th century hemp-growing bastion, was the first state to launch a multifaceted, federally approved pilot program to study the feasibility of farming fiber hemp and hemp for seed oil, as well as farming CBD-rich plants for medicinal oil extraction. It is currently legal under state and federal law for certain licensed Kentuckians to breed, cultivate, and harvest industrial hemp, formulate products, including CBD-rich oil concentrates, and ship these products across state lines.

Because Kentucky chose to operate within the context of a federally sanctioned agricultural program, local hemp farmers could access certified, pedigree seed stock from official European and Canadian sources after obtaining a Controlled Substances Import & Export Permit from the DEA. A pedigree seed supply is crucial to maintain the uniformity and consistency of a large-scale, machine-harvested crop. Today there are hundreds of cultivars available to meet the global demands for many industrial hemp products.

But industrial hemp varieties are not optimal for extracting CBD-rich oil. So Kentucky farmers sought out high-resin, CBD-rich drug plants from sources in states where cannabis is legal for therapeutic use. Bluegrass ambassadors visited CBD-rich clone repositories in Northern California and returned to Kentucky with cuttings of high-resin cannabis strains, including “ACDC,” which tips the scales at twenty percent CBD and roughly one percent THC by dry weight. By comparison, some oilseed hemp varieties weigh in at about 3.5 percent CBD max with hardly any THC, while low resin fiber hemp has even less CBD.

ACDC is the prototypical high-resin, non-euphoric, drug-type cannabis plant. It’s an excellent source of CBD-rich oil, far more prodigious than any internationally certified industrial hemp cultivar or hemp/marijuana hybrid. But ACDC does not legally qualify as industrial hemp because it slightly exceeds 0.3 percent THC by dry weight.

Colorado Cowboys

ACDC and a number of other high-CBD/low-THC cannabis strains are also being grown in Colorado under the guise of that state’s putative industrial hemp program. But Colorado’s fledgling hemp industry is not compliant with Section 7606 of the Agricultural Act of 2014.

Instead of growing hemp for research purposes as part of a federally sanctioned pilot initiative, Colorado leapfrogged official protocol and went straight to large-scale commercial cultivation. Thus, while it’s legal under state law to grow industrial hemp, make hemp products, and distribute these products within Colorado, federal law prohibits the cross-border transport and sale of Colorado hemp oil products. CBD is not legal in all 50 states, but that hasn’t stopped several Colorado start-ups (and others) from marketing CBD-rich “hemp” oil to all 50 states and beyond.

Some farmers in Colorado are actually growing high-resin, CBD-rich drug plants and calling it hemp. These “hemp” growers typically harvest their crop several weeks before maturity (i.e., before peak resin content) to keep the THC level at 0.3 percent or less. But sometimes it doesn’t work out that way.

Last year, Ryan Loflin, a Colorado farmer, was forced to destroy his entire crop because it tested at 0.5 percent THC, a smidgen over the arbitrary legal limit. This tragicomic episode underscores the folly of defining hemp, as distinct from marijuana, according to a precise THC percentage.

Whether ACDC or any other high-resin, non-euphoric, CBD-rich cannabis strain measures slightly above or slightly below the 0.3 percent THC limit won’t make any appreciable difference in terms of the quality of the CBD-rich oil extract or its therapeutic impact.

Industrial Hemp Revival

Joy Beckerman, president of Hemp Ace International, a Seattle-based consulting firm, teaches a class for law students on “The Curious Legal Status of CBD and Industrial Hemp-Derived Cannabinoids.” An industrial hemp entrepreneur and advocate for the past 25 years, Beckerman recognizes that cannabidiol has played a key role in jump-starting the creation of new infrastructure for hemp’s vast oilseed and fiber industries. Simply put, huge interest in CBD’s medicinal potential is the main reason why industrial hemp is growing again in the United States. “I see the revenue that can be immediately generated by the hemp CBD market as leading to the funding of an extensive domestic infrastructure for processing hemp fiber and seed into tens of thousands of natural and manufactured products, as well as CBD oil,” says Beckerman.

Project CBD applauds the fact that cannabidiol has helped to liberate industrial hemp from the confines of the drug abuse paradigm. Catalyzed by CBD, today’s industrial hemp revival in the United States is a major step forward that bodes well ecologically and economically. But it also highlights ongoing problems related to cannabis prohibition.

CBD has undoubtedly helped to loosen federal law with respect to industrial hemp. But current federal law prohibits American farmers from growing high-resin CBD-rich drug plants that narrowly exceed the 0.3 percent THC limit, even though these high-resin cannabis plants are much better suited for extracting CBD-rich oil than low-resin industrial hemp. Cannabis oil should be safely extracted without using toxic solvents and it should be formulated into high quality products with no artificial ingredients, chemical preservatives, poisonous thinning agents, or corn syrup.

If a large CBD-rich oil yield is the goal, then it makes little sense to decide whether a plant qualifies as a worthy source of CBD on the basis of THC content. To be clear: The best source of whole plant, CBD-rich oil is high-resin, CBD-rich cannabis—regardless of minor THC variations—that is sustainably grown without the use of pesticides or plant growth regulators. Bottom-line economics, however, may argue in favor of massive acres of seed-germinated, machine-harvested industrial hemp with 3.5 percent CBD, rather than a much smaller number of high resin cannabis plants, grown from clones, with 20 percent CBD by dry weight. Unlike with medicinal cannabis gardens, there are no plant limits for industrial hemp.

For many hemp farmers around the world, CBD oil is actually a co-product or byproduct of industrial hemp grown primarily for another purpose. Farmers can make additional money if they sell their unused hemp biomass to a business that wants to extract CBD from the leftovers. This ‘dual-use’ practice is widespread among large-scale hemp growers in Canada, for example, but it’s technically illegal, entirely unregulated, and the hemp biomass sold via underground channels is often tainted with pesticides and requires toxic solvents to extract the CBD.

Hemp Oil Issues

If grown outdoors in tested soil and carefully processed, industrial hemp can be a viable source of CBD. But it is not an optimal source of CBD-rich oil for several reasons. Industrial hemp typically contains far less cannabidiol than high-resin, CBD-rich cannabis, and huge amounts of skimpy hemp foliage are required to extract a small amount of CBD. This raises the risk of contaminants as hemp is a bio-accumulator, meaning the plant draws toxins from the soil. That’s an excellent property for phyto-remedial purposes, but it’s not so great for making ingestible medicinal oil concentrates.

Heavily refined CBD paste derived from industrial hemp foliage is poor starter material for formulating CBD-rich oil products. Both the imported hemp paste and the products infused with “pure” hemp-derived CBD powder that proliferate online typically include a thinning agent, which dilutes the oil that is heated and inhaled by vape pen users. Medical patients should beware of vape pen oil that contains propylene glycol as a thinning agent. When overheated, this chemical additive produces formaldehyde, a carcinogen, as a byproduct, according to a 2015 report in the New England Journal of Medicine. Why do so many vape oil products contain this thinning agent? It’s because of the dubious quality of the extracted material from which these unregulated vape oil products are made.

Products with heavily processed “pure” CBD derived from industrial hemp lack the full spectrum of aromatic terpenes and other cannabinoids found in high-resin drug plants. These compounds interact synergistically with CBD and THC to enhance their therapeutic effects. Scientific research shows that whole plant CBD-rich cannabis oil has a broader range of therapeutic attributes and greater therapeutic efficacy than single-molecule CBD.

As far as current federal law goes, any CBD-rich plant that exceeds 0.3 percent THC is considered marijuana and is therefore off limits for growing and extracting. But the Feds are much more lenient when it comes to pharmaceutical THC. Single-molecule THC (sold as “Marinol”) is a Schedule III drug available by prescription in all 50 states, even though it makes one as high as a kite. Schedule III is reserved for therapeutic substances with low abuse potential. Whole plant cannabis, meanwhile, continues to be classified as a dangerous Schedule I drug with no medical value.

Single-molecule compounds are the preferred domain of Big Pharma, which favors patentable isolates over “crude” whole plant synergies. It’s only a matter of time before the Food and Drug Administration gives a thumbs-up to synthetic, single-molecule, pharmaceutical CBD. The FDA, however, is generally not in the business of approving plants as medicines (though there are a few exceptions). The FDA’s single-molecule tilt reflects a cultural and political bias that privileges corporate pharmaceuticals. Single-molecule medicine is the predominant corporate way, the Big Pharma way, but it’s not the only way, and there’s scant evidence that it’s the best way to benefit from cannabis therapeutics.

The FDA Chimes In

On February 4, 2016, the FDA issued warning letters to eight CBD hemp oil retailers for making unproven medical claims about 22 different hemp-derived CBD products. The FDA also tested these products for CBD content and found some that contained no cannabidiol. This was the second round of FDA warning letters sent to CBD hemp oil businesses for product mislabeling. Some of the same products that had been previously identified as containing no CBD were still being hawked by unscrupulous internet storefronts.

Exposing fraud is necessary and laudable on the part of the FDA. That’s what a regulatory agency should do to protect vulnerable consumers. Over the years, however, the FDA has undermined its own credibility by marching in lockstep to the drug war drumbeat. On April 20, 2006, for example, the FDA dissed medical marijuana by issuing an advisory memo, which repeated the official fiction that cannabis is both dangerous and therapeutically useless.

Under the current regulatory regime, a product can’t be marketed as a medicine unless the FDA approves it as safe and effective for a specific condition. But FDA approval is no guarantee of safety or efficacy. Big Pharma, like Big Tobacco, routinely falsifies studies by hiding clinical trial data about adverse side effects and negative outcomes. And all too often, the FDA handles corporate criminals with kid gloves.

Limited by single-molecule dogma and allergic to plant compounds that can’t be patented, Big Pharma is way behind the curve with respect to cannabis therapeutics. For all its billions, Big Pharma hasn’t done much for children with intractable epilepsy. Little Charlotte Figi in Colorado, featured on CNN, wasn’t helped by Big Pharma. It was oil from a resinous CBD-rich cannabis plant that stopped her chronic seizures and saved her life.

The Seven Percent Solution

Charlotte’s Web, the CBD-rich strain that does wonders for children with Dravet’s Syndrome, isn’t a FDA-approved pharmaceutical. It came from marijuana growers in Colorado, where medicinal cannabis is legal. A lab analysis of Charlotte’s Web from ROC [Realm of Caring] Labs, dated October 16, 2013, reports the total CBD content at 7.28 percent and THC at 0.24 percent. These numbers suggest that Charlotte’s Web might be a cross between high-resin cannabis and industrial hemp. For marketing purposes, however, Charlotte’s Web was promoted as hemp and nothing but hemp.

Rumors abound regarding the origins of this strain. Its CBD content is about the same as CBD levels in certain offshoots of ‘Finola,’ a leading industrial hemp cultivar bred for nutritional seed protein and seed oil by Jace Callaway, an American medical chemist who lives in Finland. “We reliably measured CBD in ‘Finola’ samples up to eight percent in open pollinated field conditions (individual plants), but the field average is just between 3-4 percent,” Callaway told Project CBD, adding: “’Finola’ typically has a 1:15 ratio of THC to CBD. Some individual plants can be isolated and cloned from ‘Finola’ with much higher ratios . . . These are now all over the place.”

GW Pharmaceuticals, a British firm at the forefront of developing cannabis-based medications, utilizes a proprietary cultivar known as ‘Grace,’ which measures around seven percent cannabidiol and sub-0.3 percent THC. ‘Grace’ is grown outdoors in the United Kingdom. Bucking the Big Pharma trend while establishing a foothold in that sphere, GW is researching whole plant CBD-THC combinations, as well as cannabis-derived isolates.

Seven percent CBD is not nearly as attractive as twenty percent CBD (the California standard) if the goal is to grow and harvest cannabis for maximum CBD-rich oil production. European and North American botanists, accordingly, have set their sights on breeding a stable politically correct seed line with a CBD level that tops the charts and barely any THC so that it technically qualifies as industrial hemp under federal law.

The Straight Dope

When it comes to CBD-rich oil production, the 0.3 percent THC legal limit is an absurd, impractical, resin-phobic relic of reefer madness. It has become the lynchpin of cannabis prohibition, a venal, dishonest policy that impedes medical research and blocks patient access to valuable therapeutic options, including herbal extracts with various CBD:THC ratios. For patients struggling with a wide range of conditions, CBD and THC work best together, enhancing each other’s beneficial effects.

Thus far, twenty-three U.S. states have enacted medical marijuana laws and 17 states have passed versions of ’CBD-only’ laws that ostensibly permit the therapeutic use of high CBD/low THC products. None of the ‘CBD-only’ states, except for Kentucky, are in compliance with federal law regarding industrial hemp. There’s no consensus as to the proper THC limit for industrial hemp: North Carolina puts it at 0.9 percent; in Texas, it’s 0.5 percent. Each state government sets its own dysfunctional rules. Some states limit the sources of CBD-rich products and specify a narrow range of conditions for which CBD can be used; others do not.

Leading advocates for ‘CBD-only’ laws have argued that this legislation is a crucial first step toward full-fledged legalization of medical marijuana. Thus far, however, there have been no such advances in any states that passed ‘CBD-only’ laws. Most patients are not well served by ‘CBD-only’ laws. They need access to a wide spectrum of whole plant cannabis remedies, not just low THC products.

Confucius once said that to change society one must start by calling things by their real names. If maximizing CBD-rich oil output for product formulation is the objective and the best plant sources are federally illegal because of a minuscule amount of THC, then perhaps it’s time to call things by their real name. It’s not industrial hemp that’s growing when American farmers harvest their cannabis crops before full maturity to minimize THC content. These are high-resin, CBD-rich drug plants, albeit the non-euphoric kind—in essence, marijuana that doesn’t make you feel high. And marijuana is still prohibited under federal law.

Martin A. Lee is the director of Project CBD and the author of Smoke Signals: A Social History of Marijuana—Medical, Recreational and Scientific.


Sourcing CBD -- Summary:

1. Huge interest in the medicinal potential of CBD has catalyzed a rebirth of industrial hemp in the United States.

2. There are two types of cannabis plants, broadly speaking -- low resin hemp plants and high resin drug plants. Low-resin industrial hemp includes plants grown for fiber and for seed oil. High resin drug plants include euphoric THC-rich plants and non-euphoric CBD-rich plants.

3. Industrial hemp is not an optimal source of CBD-rich oil. 

4. Federal law prohibits American farmers from growing high-resin CBD-rich drug plants that narrowly exceed 0.3 percent THC, even though these high-resin cannabis plants are much better suited for extracting CBD-rich oil than low-resin industrial hemp.

5.  The 0.3 percent THC federal legal limit for industrial hemp is an aribitrary, impractical, scientifically baseless distinction designed to maintain marijuana prohibition, a disreputable policy built on a mountain of lies.

6. American farmers in Colorado and elsewhere are growing high resin CBD-rich marijuana and calling it hemp. These “hemp” growers typically harvest their crop early to minimize THC content.

7. Colorado start-ups are marketing CBD-rich oil to all 50 states, despite the fact that federal law bans the cross-border transport and sale of Colorado cannabis oil products. CBD is not legal in all 50 states.

8. The Federal Farm Bill of 2014 carved out an exemption for growing and marketing industrial hemp under the auspices of state-approved pilot research programs, but only one state thus far implemented such a program. Licensed farmers in Kentucky are currently allowed to breed, cultivate, and harvest industrial hemp, formulate products, including CBD-rich oil concentrates, and ship these products across state lines.

9. For many hemp farmers in Canada and Europe, CBD oil extraction is actually a co-product or byproduct of industrial hemp grown primarily for another purpose. Farmers earn extra money by illegally selling their leftover hemp biomass to businesses that want to extract CBD.

10. CBD and THC enhance each other’s therapeutic effects. Most medical patients need access to a wide spectrum of whole plant cannabis remedies, not just low THC products.

Copyright, Project CBD. May not be reprinted without permission.

How Safe is Your Vape Pen?

cbd vape oil
By on July 14, 2015

The Hidden Dangers of Propylene Glycol

Jahan Marcu, PhD, reports on the hidden dangers of propylene glycol and vape pens that smolder.

Portable electronic devices, known as “vape pens,” are increasingly popular among medical marijuana patients and others because they provide a convenient, discreet, and presumably benign way to administer cannabis. But how safe are vape pens and the liquid solutions inside the cartridges that attach to these devices? Who knows what’s actually being inhaled?

It’s generally assumed that vaping is a healthier method of administration than inhaling marijuana smoke, which contains noxious substances that may irritate the lungs. Since a vaporizer heats the cannabis flower or oil concentrate without burning it, the active ingredients are inhaled but no smoke is involved. At least that’s how it’s supposed to work.

But there may be a hidden downside to vape pens, which are manufactured (typically in China), marketed, and utilized without regulatory controls. Available online and in medical marijuana dispensaries, vape pens contain a battery-operated heating mechanism, which at high temperatures can transform solvents, flavoring agents, and various vape oil additives into carcinogens and other dangerous toxins.

Of particular concern: Propylene glycol, a widely used chemical that is mixed with cannabis or hemp oil in many vape pen cartridges. A syrupy, thinning compound, propylene glycol is also the primary ingredient in a majority of nicotine-infused e-cigarette solutions. At high temperatures, propylene glycol converts into tiny polymers that can wreak havoc on lung tissue.

Scientists know a great deal about propylene glycol. It is found in a plethora of common household items—cosmetics, baby wipes, pharmaceuticals, pet food, antifreeze, etc. The U.S. Food and Drug Administration and Health Canada have deemed propylene glycol safe for human ingestion and topical application. But exposure by inhalation is another matter. Many things are safe to eat but dangerous to breathe.

A 2010 study published in the International Journal of Environmental Research and Public Health concluded that airborne propylene glycol circulating indoors can induce or exacerbate asthma, eczema, and many allergic symptoms. Children were said to be particularly sensitive to these airborne toxins. An earlier toxicology review warned that propylene glycol, ubiquitous in hairsprays, could be harmful because aerosol particles lodge deep in the lungs and are not respirable.

When propylene glycol is heated by a red-hot metal coil, the potential harm from inhalation exposure increases. High voltage heat can transform propylene glycol and other vaping additives into carbonyls. Carbonyls are a group of cancer-causing chemicals that includes formaldehyde, which has been linked to spontaneous abortions and low birth weight. A known thermal breakdown product of propylene glycol, formaldehyde is an International Agency for Research on Cancer group 1 carcinogen.

Because of low oral toxicity, propylene glycol is classified by the FDA as “generally recognized as safe” (GRAS) for use as a food additive, but this assessment was based on toxicity studies that did not involve heating and breathing propylene glycol.

Prevalent in nicotine e-cig products and present in some vape oil cartridges, FDA-approved flavoring agents pose additional risks when inhaled rather than eaten. The flavoring compounds smooth and creamy (diacetyl and acetyl propionyl) are associated with respiratory illness when inhaled in tobacco e-cigarette devices. Another hazardous-when-inhaled-but-safe-to-eat flavoring compound is cinnamon ceylon, which becomes cytotoxic when aerosolized.

Currently, there is no conclusive evidence that frequent users will develop cancer or another illness if they inhale the contents of vape oil cartridges. That’s because little is actually known about the short or long-term health effects of inhaling propylene glycol and other ingredients that are present in flavored vape pen cartridges. Many of these prefilled cartridges are poorly labeled with little or no meaningful information on their contents.

The possibility that vape pens might expose people to unknown health hazards underscores the importance of adequate safety testing for these products, which thus far has been lacking.

Scientists face several challenges as they try to gather relevant safety data. As yet, no one has determined how much e-cig vapor the typical user breathes in, so different studies assume different amounts of vapor as their standard, making it difficult to compare results. Tracing what happens to the vapor once it is inhaled is equally problematic.

The biggest variable is the device itself. The performance of each vape pen can vary greatly between different devices and sometimes there is considerable variance when comparing two devices of the same model.

Some vape pens require pressing a button to charge the heating coil; others are buttonless and one activates the battery simply by sucking on the pen. The surface area of the vape pen’s heating element and its electrical resistance play a large role in converting ingestible solvents into inhalable toxins.

Another confounding factor is the scant information on when and how long the user pushes the button or inhales on average, how long the coil heats up, or the voltage used during the heating process. A five-volt setting yielded higher levels of formaldehyde in a controlled propylene glycol study cited in the New England Journal of Medicine.

In the case of vape pens, there’s a great need for specific research on how people actually use these products in the real world in order to understand potential benefits or harms.

Such studies have been conducted using the Volcano vaporizer, a first generation vaping device that differs from a vape pen, a more recent innovation, in several ways. Utilized in clinical trials as a medical delivery device, the Volcano is not a portable contraption. The Volcano only heats raw cannabis flower, not oil extract solutions, and it doesn’t combust the bud.

Vape pen manufacturers don’t like to admit it, but when the heating element gets red hot in a vape pen, the solution inside the prefilled cartridges undergoes a process called “smoldering,” a technical term for what is tantamount to “burning.” While much of the vape oil liquid is vaporized and atomized, a portion of the vape oil blend undergoes pyrolysis or combustion. In that sense, most of the vape pens that have flooded the commercial market may not be true vaporizers.

Unlike vape pen devices, the Volcano vaporizer has been tested for safety and pharmacokinetics (a measurement of what’s in the blood and how long it stays there). Collectively, the data indicate that vaporizing whole plant cannabis exposes the user to lower amounts of carcinogens compared to smoke and decreases side effects (such as reactions to the harshness of smoke).

But nonportable vaporizers like the Volcano may still pose health concerns if the vaporized cannabis flower is below acceptable botanical safety standards. A recent article in the Journal of Analytical Methods notes that high levels of ammonia are produced from vaporizing cannabis grown incorrectly, perhaps due to the lack of flushing during hydroponic cultivation. There’s a growing body of data suggesting that the chemicals used to push the plant towards unnaturally high THC concentrations stay in the finished product.

Dr. Jahan Marcu is the chief scientist for Americans for Safe Access (ASA) and chief auditor for ASA's Patient Focused Certification program. He serves on the board of various trade association and science organization committees, including the American Chemical Society, the International Association for Cannabis as Medicine, and the American Herbal Products Association.

CBD Hemp Oil Vape Cartridges with Propylene Glycol

Project CBD research associate Eric Geisterfer conducted a limited survey of cannabis vape oil and CBD hemp vape oil cartridges. Several of these products were found to include propylene glycol as an additive. The list below is incomplete—vape oil products are continually being introduced and in some cases rebranded.

Hemp oil vape cartridges that contain Propylene Glycol

  • Alternate Vape
  • Bluebird Botanicals
  • CannaVape CBD Oil
  • Cloud 9 CBD
  • Delta Liquids
  • Entourage Hemp Products also known as Cannoid LLC
  • Hemp Life Today (also known as Cannazall)
  • Hemp Pure Vape
  • Hemp Vap
  • KanaVape
  • Miracle Smoke
  • Michigan Hemp Company (also known as Bluegrass Naturals)
  • Pure CBD Vapors
  • Pure Hemp Vape
  • Tasty Hemp Oil
  • Zamnesia CBD Smart Liquid

Some cannabis vape oil cartridges also include propylene glycol or polyethylene glycol as a thinning agent. Both compounds may have adverse health effects when heated and inhaled. Neither has been safety tested by the FDA for inhalation when heated. Cannabis consumers should carefully scrutinize cannabis product labels.

    Copyright, Project CBD. May not be reprinted without permission.

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    • Jensen RP, Luo W, Pankow JF, Strongin RM, Peyton DH. Hidden Formaldehyde in E-Cigarette Aerosols. N Engl J Med. 2015;372(4):392-394. doi:10.1056/NEJMc1413069.
    • Nitzkin JL, Farsalinos K, Siegel M. More on hidden formaldehyde in e-cigarette aerosols. N Engl J Med. 2015;372(16):1575. doi:10.1056/NEJMc1502242#SA1.
    • Pomahacova B, Van der Kooy F, Verpoorte R. Cannabis smoke condensate III: The cannabinoid content of vaporised Cannabis sativa. Inhalation Toxicology. 2009;00(00):090619130156077–5. doi:10.1080/08958370902748559.
    • Wallace MS, Marcotte TD, Umlauf A, Gouaux B, Atkinson JH. Efficacy of Inhaled Cannabis on Painful Diabetic Neuropathy. J Pain. 2015;0(0). doi:10.1016/j.jpain.2015.03.008.

    CBD Misconceptions

    Cannabis misconceptions, marijuana misinformation
    By on February 18, 2015

    Updated: August 2, 2015

    It doesn’t get you high, but it’s causing quite a buzz among medical scientists and patients. The past year has seen a surge of interest in cannabidiol (CBD), a non-intoxicating cannabis compound with significant therapeutic properties. Numerous commercial start-ups and internet retailers have jumped on the CBD bandwagon, touting CBD derived from industrial hemp as the next big thing, a miracle oil that can shrink tumors, quell seizures, and ease chronic pain—without making people feel “stoned.” But along with a growing awareness of cannabidiol as a potential health aid there has been a proliferation of misconceptions about CBD.

    1. “CBD is medical. THC is recreational.” Project CBD receives many inquiries from around the world and oftentimes people say they are seeking “CBD, the medical part” of the plant, “not THC, the recreational part” that gets you high. Actually, THC, “The High Causer,” has awesome therapeutic properties. Scientists at the Scripps Research Center in San Diego reported that THC inhibits an enzyme implicated in the formation of beta-amyloid plaque, the hallmark of Alzheimer’s-related dementia. The federal government recognizes single-molecule THC (Marinol) as an anti-nausea compound and appetite booster, deeming it a Schedule III drug, a category reserved for medicinal substances with little abuse potential. But whole plant marijuana, the only natural source of THC, continues to be classified as a dangerous Schedule I drug with no medical value.
    2. “THC is the bad cannabinoid. CBD is the good cannabinoid.” The drug warrior’s strategic retreat: Give ground on CBD while continuing to demonize THC. Diehard marijuana prohibitionists are exploiting the good news about CBD to further stigmatize high-THC cannabis, casting tetrahydrocannabinol as the bad cannabinoid, whereas CBD is framed as the good cannabinoid. Why? Because CBD doesn’t make you high like THC does. Project CBD categorically rejects this moralistic, reefer madness dichotomy in favor of whole plant cannabis therapeutics. (Read the foundational science paper: A Tale of Two Cannabinoids.)
    3. “CBD is most effective without THC.” THC and CBD are the power couple of cannabis compounds—they work best together. Scientific studies have established that CBD and THC interact synergistically to enhance each other’s therapeutic effects. British researchers have shown that CBD potentiates THC’s anti-inflammatory properties in an animal model of colitis. Scientists at the California Pacific Medical Center in San Francisco determined that a combination of CBD and THC has a more potent anti-tumoral effect than either compound alone when tested on brain cancer and breast cancer cell lines. And extensive clinical research has demonstrated that CBD combined with THC is more beneficial for neuropathic pain than either compound as a single molecule.
    4. “Single-molecule pharmaceuticals are superior to ‘crude’ whole plant medicinals.” According to the federal government, specific components of the marijuana plant (THC, CBD) have medical value, but the plant itself does not have medical value. Uncle Sam’s single-molecule blinders reflect a cultural and political bias that privileges Big Pharma products. Single-molecule medicine is the predominant corporate way, the FDA-approved way, but it’s not the only way, and it’s not necessarily the optimal way to benefit from cannabis therapeutics. Cannabis contains several hundred compounds, including various flavonoids, aromatic terpenes, and many minor cannabinoids in addition to THC and CBD. Each of these compounds has specific healing attributes, but when combined they create what scientists refer to as a holistic “entourage effect,” so that the therapeutic impact of the whole plant is greater than the sum of its single-molecule parts. The Food and Drug Administration, however, isn’t in the business of approving plants as medicine. (See the scientific evidence.)
    5. “Psychoactivity is inherently an adverse side effect.” According to politically correct drug war catechism, the marijuana high is an unwanted side effect. Big Pharma is keen on synthesizing medically active marijuana-like molecules that don’t make people high—although it’s not obvious why mild euphoric feelings are intrinsically negative for a sick person or a healthy person, for that matter. In ancient Greece, the word euphoria meant “having health,” a state of well-being. The euphoric qualities of cannabis, far from being an unwholesome side effect, are deeply implicated in the therapeutic value of the plant. “We should be thinking of cannabis as a medicine first,” said Dr. Tod Mikuriya, “that happens to have some psychoactive properties, as many medicines do, rather than as an intoxicant that happens to have a few therapeutic properties on the side.”
    6. “CBD is legal in all 50 states.” Purveyors of imported, CBD-infused hemp oil claim it’s legal to market their wares anywhere in the United States as long as the oil contains less than 0.3 percent THC. Actually, it’s not so simple. Federal law prohibits U.S. farmers from growing hemp as a commercial crop, but the sale of imported, low-THC, industrial hemp products is permitted in the United States as long as these products are derived from the seed or stalk of the plant, not from the leaves and flowers. Here’s the catch: Cannabidiol can’t be pressed or extracted from hempseed. CBD can be extracted from the flower, leaves, and, only to a very minor extent, from the stalk of the hemp plant. Hemp oil start-ups lack credibility when they say their CBD comes from hempseed and stalk. Congress may soon vote to exempt industrial hemp and CBD from the definition of marijuana under the Controlled Substances Act. Such legislation would not be necessary if CBD derived from foreign-grown hemp was already legal throughout the United States. (Read more: Sourcing CBD: Marijuana, Industrial Hemp & the Vagaries of Federal Law)
    7. “'CBD-only’ laws adequately serve the patient population.” Fifteen U.S. state legislatures have passed “CBD only” (or, more accurately, “low THC”) laws, and other states are poised to follow suit. Some states restrict the sources of CBD-rich products and specify the diseases for which CBD can be accessed; others do not. Ostensibly these laws allow the use of CBD-infused oil derived from hemp or cannabis that measures less than 0.3 percent THC. But a CBD-rich remedy with little THC doesn’t work for everyone. Parents of epileptic children have found that adding some THC (or THCA, the raw unheated version of THC) helps with seizure control in many instances. For some epileptics, THC-dominant strains are more effective than CBD-rich products. The vast majority of patients are not well served by CBD-only laws. They need access to a broad spectrum of whole plant cannabis remedies, not just the low THC medicine. One size doesn’t fit all with respect to cannabis therapeutics, and neither does one compound or one product or one strain. (Read more: Prohibition’s Last Gasp: “CBD Only.”)
    8. “CBD is CBD—It doesn’t matter where it comes from.” Yes it does matter. The flower-tops and leaves of some industrial hemp strains may be a viable source of CBD (legal issues notwithstanding), but hemp is by no means an optimal source of cannabidiol. Industrial hemp typically contains far less cannabidiol than CBD-rich cannabis. Huge amounts of industrial hemp are required to extract a small amount of CBD, thereby raising the risk of toxic contaminants because hemp is a “bio-accumulator” that draws heavy metals from the soil. Single-molecule CBD synthesized in a lab or extracted and refined from industrial hemp lacks critical medicinal terpenes and secondary cannabinoids found in cannabis strains. These compounds interact with CBD and THC to enhance their therapeutic benefits. (See also: Sourcing CBD: Marijuana, Industrial Hemp & the Vagaries of Federal Law.)

    Copyright, Project CBD. May not be reprinted without permission.

    On The Frontiers Of Hemp Science

    Hemp science
    By on February 16, 2015

    The original name of the ICRS was “International Cannabis Research Society.” In 1995—after the body’s own cannabinoid receptor system had been discovered and elucidated by ICRS members—the group changed the C-word in its name to “Cannabinoid.” As pharmacologist Dale Deutsch explained in 1998, “The field is moving away from the plant.”

    The 2014 ICRS meeting marked the return of the plant to the forefront of the field. Neurologist Ethan Russo was serving as president (the job is held for a year), and he invited the Italian natural product chemist Giovanni Appendino to give the featured talk.

    Appendino, a professor at the Università del Piemonte Orientale, noted proudly that he is from Carmagnola, a northern Italian town renowned for its fiber hemp variety of the same name.
    Appendino first published research in the cannabinoid field in 2002, when he was co-author of a paper on “Noladin ether—a putative endocannabinoid.” The lead authors were Raphael Mechoulam and Vincenzo DiMarzo. But his “relationship with cannabis as fiber hemp” goes much further back, he said. “My grandfather was growing it and the odor of hemp retting tanks filled the air around Carmagnola during the Fall.”

    “Nature has varied on the cannabinoid structure,” Appendino observed. Cannabis researchers have focused almost e. xclusively on THC, CBD, CBC (cannabichromene), and CBG (cannabigerol, precursor to the other three) while not investigating the therapeutic potential of related molecules present in Cannabis — and other plants as well.

    Similarly, by defining cannabinoids as drugs that work at the CB1 and CB2 receptors (the canonical cannabinoid receptors concentrated in the central and peripheral nervous system, respectively), researchers may be overlooking beneficial compounds in Cannabis that work by other mechanisms.

    In the course of screening more than 200 varieties of fiber hemp, Appendino and colleagues have found significant quantities of obscure compounds whose medical potential he considers “worthy of investigation.”

    He touched briefly on canniprene, the cannflavins, cannabinoid esters, and “sesqui-CBG,” which Appendino’s group isolated from a fiber hemp variety.

    Appendino has encountered a hemp variety containing two percent canniprene—a compound he called “the Cannabis version of resveratrol” (a beneficial antioxidant compound present in red grapes).

    From others varieties of hemp he isolated the prenylated version of cannbigerol—meaning CBG with a prenyl group attached. Prenylation entails the addition of a hydrophobic molecule to a protein or chemical compound, which may facilitate lipid binding to cell membranes.

    There is no reason, Appendino said, that marijuana should not also produce the prenylated version of THC—which would have distinct biological activity.

    Cannabinoids not unique to Cannabis

    Cannabinoids are not unique to cannabis—they have been found in other plants. Appendino reported that a large amount of CBG and its carboxylic precursor (CBGA) had been isolated from a specific Helichrysum variety found only in South Africa.

    Studying how Helichrysum makes “non-cannabis” CBG and its related compounds has been difficult for Appendino and his colleagues, because strict South African bio-piracy laws prohibit the collection and export of native species or their seeds. These laws, designed to prevent foreign corporate exploitation of the country’s unique genetic resources, also impede legitimate scientific research. After two years of bureaucratic red tape, Appendino was only able to obtain a small vial of extract from Helichrysum, and has not been able to obtain seeds of the plant to continue his research.

    Appendino discovered that cannabinoid-like compounds are made by plants “apart from the normal cannabinoid biosynthetic route. There is a new pathway that starts from an aromatic acid.” Referred to as the “Helichrysum cannabinoids,” these compounds also have been detected in liverwort, a diuretic herb helpful for bronchitis and liver congestion, as well as gallbladder, kidney, and bladder problems.

    Helichrysum is used in African ethno-pharmacology, Appendino explains, “like hemp, to make fumes in ritual ceremonies” and that a “psychotropic effect...similar to cannabinoids,” might ensue.


    Appendino also discussed some of the therapeutic attributes of terpenoids, the largest class of naturally occurring compounds on the planet. Terpenoids, or terpenes, are the chemicals that give plants their unique smells and flavors. Found in high concentrations in many culinary herbs and spices, terpenes not only provide flavor and scent, they are also important signaling chemicals that plants use to communicate with insects.

    Some plants up-regulate specific terpenes when attacked by herbivores to render the plant less palatable to the attacking insect. In a beautiful demonstration of the web that Mother Nature has created, these same terpenes have been shown to recruit parasitic bugs that themselves attack the herbivores which are eating the plant!

    Present in black pepper, bitter leafy greens, Echinacea, and many cannabis strains, beta-caryophyllene is one of the terpenes that plants use to defend themselves against predators.

    Terpenes are synthesized by the plant from five-carbon isoprene units, two of which come together in specialized cellular compartments to form the 10-carbon monoterpenes (limonene, pinene, linalool, terpinolene, et al). The 15-carbon sesquiterpenes, such as β-caryophyllene, differ from the monoterpenes by the incorporation of an extra isoprene unit. (β is the Greek letter beta.)

    Monoterpenes are more volatile at lower temperatures, so when Cannabis is dried, stored for periods of time, or made into extracts, the monoterpenes are generally first to evaporate while the sesquiterpenes like β-caryophyllene are more likely to remain.

    Appendino recounted how the wild, ancestral relative of corn, teosinte, grown by the Mayan and Incan farmers in pre-European Central and South America, produced significant amounts of β-caryophyllene before modern breeders selected towards high yielding corn with an increased sugar content. The drive to breed high-yielding varieties of corn for intensive commercial agriculture sacrificed the ability of the plant to produce β-caryophyllene .

    At the 2007 ICRS meeting, Jürg Gertsch reported that β-caryophyllene binds specifically to the CB2 cannabinoid receptor, which regulates immune function and is found mainly outside the central nervous system.

    Big Pharma has taken note of CB2’s role as an immune cell modulator. But the CB2 receptor has yet to be successfully exploited by the pharmaceutical industry, observed Appendino in 2014: “If drug discovery is a sea, then CB2 is a rock that is surrounded by shipwrecked-projects,” he commented poetically.

    Pharmaceutical companies have spent large sums investigating proprietary synthetic CB2-selective compounds that end up showing little clinical efficacy. “But β-caryophyllene is a special lottery ticket,” said Appendino.

    β-caryophyllene seems like the Cannabis plant’s own perfect key for nature’s CB2 lock. Appendino described how the β-caryophyllene molecule interacts with the CB2 receptor. It’s an unusual physical relationship for cannabinoid-type agonists. β-caryophyllene does not look like any other molecule that binds to the cannabinoid receptors.

    Known to be anti-inflammatory and easy on the stomach lining, plant extracts high in β-caryophyllene have produced analgesic and anti-inflammatory effects in clinical trials. “Maybe the interaction of β-caryophyllene with CB2 is an echo of an ancient dialog between plants and insects,” Appendino mused.

    Expanded-Definition Cannabinoids (EDCs)

    Just as natural selection tinkers with compounds, so do scientists, hoping to find a useful modification that evolutionary pressure hasn’t induced nature to come up with. Research is underway into some of the unorthodox cannabinoids Appendino discussed.

    Appendino’s expanded concept of cannabinoid drugs involves an expanded concept of the endocannabinoid system. In addition to CB1 and CB2, the biological targets of the EDCs include the GPR55 receptor; transcription factors in the mitochondria that switch genes on and off; and TRP (pronounced “trip”) receptors, which function as ion channels with gates that open and close to transmit signals. CBD, CBG, and other phytocannabinoids bind to various TRP receptors.

    A Spanish biotech company called VivaCell has developed a drug, VCE-003, in which a quinol group has been attached to CBG.  VCE-003 outperforms CBG in activating PPAR receptors, which are situated on the cell’s nucleus and regulate gene expression and metabolic function. VCE-003 has shown efficacy in studies using mouse models of Multiple Sclerosis and Encephalomyelitis.

    Drugs like VCE-003 are known as “semi-synthetics.” Hydrocodone and buprenorphine, which have replaced codeine and morphine and most opioid analgesics now sold in the U.S., are well-known semi-synthetics.

    The process by which a semi-synthetic drug is created can be patented, whereas a natural product cannot be patented. This raises the question of whether such drugs are in fact superior for medical reasons or for commercial purposes.