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Only 5% of Canadian cannabis tests positive for pesticides

Published on December 9, 2019 · Last updated July 28, 2020
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Jesse Milns/Leafly

Data released by Health Canada in response to a Global News Access to Information request revealed 95% of cannabis produced by licensed cultivators tested negative for pesticides during the period between November 2018 and February 2019.

During that time, Health Canada conducted 133 tests, finding restricted pesticides in five products. In four of the five cases, the substances were within allowable limits, while in one case, a sample contained dangerous levels of mildew-killer myclobutanil, which is carcinogenic and toxic when burned.

Myclobutanil has been at the heart of several major medical-cannabis contamination scandals.

Health Canada conducted 160 unannounced tests in 2017, finding pesticides in nearly 40 of them, and myclobutanil in 28 samples of dry flower.

At the beginning of 2017, Organigram lost its organic certification and recalled 69 lots of products when that tested positive for myclobutanil, after which the company was the target of a class action lawsuit.

Later that same year the Globe and Mailreported that licensed medical cannabis producer Mettrum (acquired in 2016 by Canopy and rebranded Mettrum Spectrum) had deliberately applied the toxic fungicide beginning as early as 2014, hiding containers of the banned chemical in ceiling tiles.

Also in 2017, products from Hydropothecary (now Hexo) tested positive for banned pesticides including myclobutanil, as did products from Broken Coast and Peace Naturals.

Once left to test its own products and police its own behaviour, the industry lost Health Canada’s trust by the end of 2017, when the agency introduced fines of up to $1 million for products testing positive for banned pesticides.

This series of scandals meant prior to adult-use legalization, many saw the medical cannabis sector as a wild west of lawless pesticide application—a stereotype producers were happy to try to escape, praising Health Canada’s aggressive action on pesticides, and embracing biological pest control over chemical agents.

Two years down the road and several months into legalization, Health Canada began forcing LPs to send product samples to independent labs for pesticides screening.

While some critics are still concerned about the 5% of cannabis that did test positive for banned materials, all agree it’s an improvement on 2017.

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Jesse B. Staniforth
Jesse B. Staniforth
Jesse Staniforth reports on cannabis, food safety, and Indigenous issues. He is the former editor of WeedWeek Canada.
View Jesse B. Staniforth's articles
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