Contaminant Analysis of Illicit vs Regulated Market Extracts

Anresco analyzed a series of illicit market samples and found most were adulterated with high levels of vitamin e acetate — a compound frequently linked to the recent vaping crisis. Additionally, all samples failed the California BCC’s limits for pesticides, in some cases at hundreds of times the permitted level.

Zachary Eisenberg, Derek Moy, Vu Lam, Cathy Cheng, Josh Richard, Benjamin Burack

Key Findings

– We found no evidence of vitamin E acetate adulteration in regulated-market cartridges produced by California-licensed producers.  Of the 200+ regulated cartridges tested, not one was found to have significant concentrations of vitamin E acetate.

– We found a high degree of vitamin E acetate contamination in illicit market samples.  Of the 15 illicit-market cartridges tested, 9 had been adulterated with vitamin E acetate at concentrations of 20-50%.

– We found an alarmingly high degree of pesticide contamination in illicit market samples.  Of the 10 illicit-market cartridges we tested for pesticides, all 10 failed for multiple pesticides and all contained at least one pesticide at 20x the legal limit.  One sample contained myclobutanil, a pesticide that partially converts to hydrogen cyanide upon combustion, at over 700x the legal limit.

– In summary, we found dramatic differences in contamination between licensed regulated-market cartridges and illegal illicit-market cartridges.  Other quality issues likely exist for the latter and they are not fit for consumption

The Vaping Crisis

In recent months ~1,600 lung injury cases and 34 deaths have been reported to the CDC relating to e-cigarette and/or vaping usage.  No single compound has been identified in all suspect samples collected, complicating a diagnosis of the direct cause.  However, a majority of the samples tested contained significant levels of vitamin e acetate (tocopheryl acetate), a recently popularized diluent implicated in at least 6 previous cases of lipoid pneumonia.  While there is significant evidence to suggest there may be other issues contributing to the crisis instead of or in addition to vitamin E acetate, the compound is the primary focus of a number of states (Colorado, New York,, Others).

Anresco recently analyzed a variety of samples for vitamin e acetate and also pesticides (another potential contributor to the recent crisis).  Our findings are presented along with context in this article.

The Illicit Market

Unregulated products have been determined to be the proximate cause of all cannabis-related cases within the State of California and almost all reported cases nationwide.  Almost two years after recreational legalization, the illicit in California is estimated to be almost 3x the size of the regulated market, and is projected to retain a majority share of overall cannabis revenue until 2024.  To illustrate, there are currently an estimated 2,835 unlicensed dispensaries and delivery services in the State and only 873 licensed sellers.  

There is a long history of quality issues in the unregulated cannabis market.  That is why the California Bureau of Cannabis Control (BCC) requires that all regulated products undergo testing prior to sale to the general public.  In the case of inhalable extracts, they must be tested for cannabinoids, pesticides, heavy metals, pathogens, mycotoxins, foreign material, and residual solvents.  Achieving the contaminant limits set by the state are extremely challenging and legal operators dedicate a considerable amount of time and resources to develop clean supply chains.  Additionally, since regulated products must be labeled accurately, operators are incentivized to produce high potency extracts, as these sell for a premium.  

The unregulated market on the other hand contains no such economic incentives for quality or safety.  Pesticides are overused because cannabis yields can be significantly affected by a variety of insects, mold, and mildew.  Cartridges containing heavy metals are utilized because they are cheap and widely availableHarmful residual solvents remain because it is costly and/or time consuming to have them removed.  Lastly, and perhaps most relevantly to the recent outbreak, diluents are utilized to dramatically increase profit margins.

Potential Increase in Profitability for Cutting Distillate:

Estimated Value of Distillate: $6,000/liter

Estimated Cost of Distillate Manufacture: $4,000/liter

Estimated Cost of Vitamin E Acetate: $200/liter

Estimated Overhead: $1,400/liter

Estimated Profit of Distillate: $6,000 – $4,000 – $1,400 = $600/liter (10%)

Estimated Profit of Cut Distillate: $6,000 – ((½ x $4,000) + (½ x 200)) – $1,400 = $2,500 (~41.6%)

$2,500 / $600 = ~416% increase in profit

Vitamin E Acetate

Vitamin E acetate is the oil derivative of vitamin E (a naturally occurring compound in plants), commonly used in foods, supplements, and cosmetics, that has only recently been popularized as a cutting agent in cannabis extracts.  Previously a variety of other diluents such as Polypropylene Glycol (PPG), Propylene Glycol (PG), Polyethylene Glycol (PEG), Vegetable Glycerin (VG), and Ethylene Glycol (EG) were widely utilized for the same purpose.  (While there have been concerns regarding the safety of inhaling these other compounds at high levels, there have been no previous outbreaks linked to their usage.)  From an illicit manufacturer’s perspective — the problem with these other diluents is they turn extracts they are mixed with noticeably less viscous and lighter in color.  Vitamin E acetate, on the other hand, does not noticeably change the look or feel of the extract when added – an important distinction for discerning customers who are known to perform “air bubble” tests to evaluate quality.  This has lead to its rapid adoption by illicit operators.

After vitamin E acetate became a compound of concern, Anresco developed a method to analyze for it via liquid chromatography triple quadrupole mass spectrometry (LC-MS/MS).  The advantages of this method relative to others that have been developed are the ability to detect trace levels of the compound and achieve clear chromatographic separation from other potential coeluting compounds (i.e. to prevent false positive detections). 

Example chromatogram from Anresco’s LC-MS/MS

Anresco has now tested over 200 samples from various licensed operators within the State of California.  We also tested 15 samples purchased from unregulated operators (located via Weedmaps) for comparison. Our findings are graphed below:

9 of the 15 samples illicit market samples contained vitamin e acetate at over 20%, with a few at close to 50%.  Comparatively, none of the 200+ samples from the regulated market showed signs of adulteration.


The cannabis industry has a long history of issues with pesticides.  The problem is exacerbated in extracts, because the process of concentrating cannabinoids also concentrates pesticides (and other contaminants as well).  Unlike vitamin E acetate, there is pesticide usage data from samples prior to regulation, from the current regulated market, and from the current illicit market. 

When Anresco first offered its analytical services to the cannabis industry, it acted as the testing laboratory for a popular consumption event, qualifying products submitted for various contests.  Over 80% of the products tested failed Oregon’s action limits for pesticides (which are considered to be less exacting than California’s).  This figure was in line with what other laboratories were finding prior to regulation (1, 2).

We also have data from the regulated market, now that is has stabilized.  The most recent BCC report found that 602 of 16,049 batches tested failed for pesticides (~3.75%).  Those samples that failed either had to be destroyed or remediated, so they were not brought to market.  

There was very little data on the incidence of pesticide usage in the current illicit market because these operators operate outside the regulatory framework requiring testing.  So, Anresco acquired and tested 10 illicit market samples for pesticides. Their results are graphed below:

Every illicit sample failed for multiple pesticides regulated by the California BCC, often at alarming levels.  For example, we detected myclobutanil, a pesticide that degrades into hydrogen cyanide upon combustion, at over 70ppm in one sample.  That’s over 700 times the limit permitted by the BCC.  (Testing Anresco performed on behalf of Leafly showed even higher levels of contamination — with one sample at over 5000 times the legal limit.  On average, each sample failed for 10.36 pesticides and all samples had at least 1 pesticide present at over 20x the legal limit.


There are clear quality and safety differences between unregulated and regulated market samples.  A majority of the illicit samples we tested contained vitamin E acetate at significant levels, whereas a large sample size of the legal market showed no such issues.  Ditto, every single illicit sample contained multiple pesticides at levels tens or hundreds of times the limit permitted by the Bureau of Cannabis Control, whereas the regulated market has largely eliminated this problem.  Had additional tests been performed on the illicit samples to evaluate label claims or test for other contaminants, it is very likely they would have failed for those tests as well.

While it is still unclear what exactly is causing illnesses resulting from cannabis vaping, it does appear evident that the unregulated market is largely if not exclusively at fault and that more needs to be done to prevent these unsafe products from reaching consumers.  Anresco, for its part, is committed to working with cannabis companies, regulators, and stakeholders to assure safety of the regulated market and identify the cause(s) of the vaping crisis.

To ensure clean, tested product from licensed dispensaries, visit to verify a retailer’s license.

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Anresco would like to thank all the companies that proactively submitted samples for this study and participated in the drafting of this article.  We found no evidence of vitamin E acetate adulteration in these regulated-market cartridges produced by California-licensed producers.