By / September 5, 2023

92% of Illegal Cannabis in Canada Contains Pesticides, Study Finds

A recent study published in the Journal of Cannabis Research has shed light on the widespread presence of pesticides in both illegal and legal cannabis in Canada.

Research Methodology and Findings

In the paper titled “High Levels of Pesticides Found in Illicit Cannabis Inflorescence Compared to Licensed Samples in Canadian Study Using Expanded 327 Pesticides Multiresidue Method,” researchers compared 36 cannabis samples from authorized dispensaries and 24 from illegal commerce. These illegal samples had been seized by law enforcement and were submitted to Health Canada for laboratory testing in 2021.

The researchers searched for traces of 327 different pesticides in the samples and found that a large number of illegal cannabis samples contained harmful chemicals.

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Highlighted Concerns: Unique Active Ingredients and High Frequency

“The study found that pesticides were detected in 92% of samples from illegal cannabis inflorescences in Canada, with 23 unique active ingredients of pesticides quantified,” the study states. “Four pesticides and synergists (myclobutanil, paclobutrazol, piperonyl butoxide, and pyrethrins) were detected at a high sampling frequency, from eight to 17 times out of a total of 24 illegal samples.”

Pesticide Variety in Illegal Samples

They also noted that one illegal sample contained nine pesticide ingredients, but on average, the illegal samples contained 3.7 different pesticides, with 87% of them containing more than one pesticide.

Comparison With Legal Cannabis

The researchers provided a table showing which pesticides were found in the authorized and illegal samples. Only 6% of the legal samples tested positive for pesticides, including only dichlobenil and myclobutanil.

Need for Further Research

Lastly, they note that studies of this nature are not yet common. “To the authors’ knowledge, this study is the only in-depth multiresidue analysis of pesticides that compares pesticides in the authorized and illegal cannabis markets in a national jurisdiction where cannabis has been legalized,” concludes the study.

Government Warnings Supported by Study

“Although this is a small study, our findings support the message from the Government of Canada that consuming illegal products could result in adverse effects and other serious harm. Tests conducted on illegal cannabis have revealed the presence of contaminants such as pesticides and unacceptable levels of bacteria, lead, and arsenic,” the study further elaborated.

(Featured image by CRYSTALWEED Cannabis via Unsplash)

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