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2023 Report: Maine's Medical Cannabis is Contaminated

Updated: Dec 23, 2023

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Maine's Medical Cannabis is Contaminated

A 2023 report entitled "Harmful Contaminants in Maine's Medical Cannabis Program" from Maine's Office of Cannabis Policy (OCP) detailed audit testing conducted on a sample of the state's medical cannabis products. The report's authors explained that testing medical cannabis and medical cannabis products for potentially harmful contaminants is voluntary in Maine.

The shocking report (linked below) included the official Certificates of Analysis from independent testing laboratories for each medical cannabis sample examined during the audit.

A row of boats in Maine.
Maine's cannabis is contaminated.

Importance of Cannabis Testing

Maine's Medical Cannabis is Contaminated. Observed the study's authors: "Testing cannabis generally is important for preventing both acute reactions and complications due to chronic exposure, regardless of the consumer of the cannabis or cannabis product." They explained that hemp and marijuana are akin to "bio-accumulators" that work "as a sponge to [their] environmental surroundings, absorbing contaminants and nutrients...from the air, water, and soil."

"Hemp and marijuana are akin to 'bio-accumulators' that work as a sponge to [their] environmental surroundings, absorbing contaminants and nutrients."

The researchers reported that cannabis is so good at this task that it has been employed to extract contaminants from soil, a process which is officially called phytoremediation. "A particularly notable use of the cannabis plant as a phytoremediator is its use to purge soil contaminated by radiation released during the Chernobyl nuclear meltdown in 1986," noted the scientists.

A room full of cannabis in a commercial garden.
Testing not mandatory in Maine

Maine's Medical Cannabis is Contaminated Report

Maine's Medical Cannabis is Contaminated. Maine's OCP performed audit testing on 120 samples obtained from licensed participants in the state's medical cannabis program. It found that 50 samples (42 percent) featured at least one contaminant "that would have failed testing according to the mandatory testing standards set for Maine's Adult Use Cannabis Program."

The audit testing discovered the following:

  • 30 samples failed for yeast and mold (25 percent of samples)

  • 21 samples failed for pesticides (18 percent)

  • Three samples failed for heavy metals (three percent)

  • One sample failed for filth and foreign materials (0.8 percent)

A total of 12 samples (10 percent of those investigated) failed in multiple categories. Four samples featured multiple pesticides (the audit found a total of 26 pesticide failures). There were four heavy metal failures, with one sample characterized by multiple heavy metal failures.

A lighthouse on the shore of Maine.
Is Maine cannabis safe?

Maine's Medical Cannabis is Contaminated Report Conclusions

Maine's Medical Cannabis is Contaminated. The report published the following conclusions:

"Historically, public discussions in Maine about mandatory testing have lacked data and information about contamination within the supply chain. OCP's recent audit testing of medical cannabis aimed to help fill that gap and bring sound, reliable data to the conversation.

42 Percent of Samples Failed

"The fact that 42 percent of medical cannabis samples taken at random contained at least one contaminant at levels that would have failed testing in Maine's adult use program cannot be taken lightly, as these very same products are being offered to patients with serious medical conditions every day. The harmful effects of these cannabis contaminants are discussed at length in this report, and their known prevalence within the supply chain must serve to reset discussions around medical cannabis testing.

"42% of medical cannabis samples contained at least one contaminant at levels that would have failed testing in Maine's adult use program."

"Maine's Medical Use of Cannabis Program has evolved dramatically since Maine legalized medical cannabis in 1999 and established the program's statutory framework in 2010. Early on in the program, Maine's registered caregivers were each cultivating and producing cannabis and cannabis products for a small number of patients with whom they had individual relationships.

106,000 Patients at Risk

"Today, however, medical program participants are serving more than 106,000 patients statewide rather than a handful of patients each. Similarly, at the inception of Maine's medical program, mandatory testing was not a universal best practice; while today, mandatory cannabis testing in medical and adult use programs (including Maine's adult use program) is a national standard—a standard Maine's medical program fails to meet.

"Maine's medical cannabis laws have not kept up with these state and national changes, and they do not go far enough in protecting the state’s vulnerable patients who use cannabis as medicine.

A greenhouse full of cannabis plants.
Should Maine make testing mandatory?

"Arguments against mandatory testing have historically included misinformation and criticism about Maine's certified cannabis testing facilities (CTFs). For a testing facility to accept and analyze cannabis samples in Maine's Adult Use Cannabis Program, they must go through a lengthy and rigorous accreditation and certification process with the state, plus they must attain accreditation from an independent, third-party accreditor, ISO/IEC, an international standard for demonstrating competent facility operation and valid results.

"In its own analysis to investigate claims of inconsistent potency test results by Maine CTFs, OCP found there to be no bias and a high degree of comparability between the three CTFs operating throughout the two-year period analyzed.

"Implementing mandatory medical cannabis testing is but one part of protecting Maine's medical cannabis patients as multiple reforms are necessary."

"The rigorous standards set for Maine CTFs are detailed throughout this report so that accurate information is available for future discussions about mandatory testing. Maine's reliable and accurate certified testing facilities have the capacity and expertise to keep Maine's medical cannabis supply chain free of harmful contaminants.

Mandatory Cannabis Testing?

"Implementing mandatory medical cannabis testing is but one part of protecting Maine's medical cannabis patients as multiple reforms are necessary to modernize Maine's medical cannabis program. Identifying harmful contaminants in the medical cannabis supply chain is important, but absent an inventory tracking system and changes to the confidentiality protections for program registrants, the impacts of such mandatory testing are limited at best.

"Maine's 106,000+ medical cannabis patients deserve a comprehensive solution that prioritizes their health and safety, and the primary goal of future policy conversations around mandatory medical cannabis testing must be to keep Maine's patients safe."

View the original report.

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