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The term “pesticides” includes herbicides, insecticides and fungicides.

The industry promised that genetically modified (GM, also called genetically engineered) crops would reduce the use of pesticides in farming. Instead, herbicide use has increased with the use of GM crops. CBAN’s latest research has found that herbicide sales in Canada increased by 199% since genetically engineered herbicide-tolerant crops were introduced (1994-2016). This number is an update from the details in our report “Are GM crops better for the environment?”

Almost 100% of the GM crops grown in Canada are herbicide-tolerant.

New CBAN Factsheet:
Genetically Modified Crops and Herbicides, November, 2018

Take Action

  1. Petition calling for the federal government conduct an independent review and withdraw the registration of glyphosate in Canada. Posted by Equiterre. November 2018.
  2. Petition calling for stronger laws for pesticide approvals in Canada. Posted by Environmental Defence. September 2018.


New Factsheet: Genetically Modified Crops and Herbicides

•    Almost 100% of all GM crops grown in Canada are genetically modified to be herbicide-tolerant.
•    Herbicide sales are up by 199% since GM crops were introduced in Canada (1994-2016).
•    Many, or most, genetically modified crops are now tolerant to more than one herbicide.

Download CBAN’s factsheet.

Health Canada reviewing studies used to approve glyphosate safety

November 12, 2018: A preliminary review of evidence in the US court case Dewayne Johnson v. Monsanto Company shows that many studies used to evaluate the safety of the herbicide ingredient glyphosate involved the company Monsanto. The company (now owned by Bayer) had an uncredited role in many safety studies and many of these same studies were also used by Health Canada in their safety review. Health Canada has called these “troubling allegations” and has started to review the studies behind its evaluation of glyphosate’s safety.

“Transparency and disclosure of all authors and their conflicts of interest are central tenants of scientific ethics and science-based decision making.” The Canadian environmental groups Canadian Association of Physicians for the Environment, Environmental Defence, Equiterre, David Suzuki Foundation, Prevent Cancer Now have written a letter detailing the compromised studies and requesting a review panel.

Court Case: Dewayne Johnson v. Monsanto Company

“This case is way bigger than me. I hope it gets the attention that it needs.”
– Dewayne Johnson, former school groundskeeper awarded $78 million from Monsanto

November 2018: A judge has cut the $289 award to Dewayne “Lee” Johnson down to $78 million. However, the judge did not overturn the decision (see below) as she indicated she might, after jurors in the initial case wrote to defend their ruling and process.

August 2018: A California jury reached a verdict in a personal liability lawsuit against Monsanto, in the case of Dewayne Johnson, finding that Monsanto’s glyphosate product, Roundup, caused a school groundskeeper’s terminal non-Hodgkin lymphoma. The jury not only found that Roundup caused the plaintiff’s cancer, awarding him $39.3 million in pain and suffering and economic damages, but also that Monsanto acted “with malice or oppression” and awarded an additional $250 million in punitive damages. Read the article in The Guardian “One Man’s Suffering Exposed Monsanto’s Secrets to the World” by Carey Gillam.

Glyphosate gives way to Dicamba

As glyphosate-resistant weeds spread across North America and the herbicide glyphosate loses its power as a weed-killer, Monsanto is replacing its GM glyphosate-tolerant soy with GM dicamba-tolerant soy. In the US, the new dicamba-tolerant varieties are increasing the use of dicamba. Monsanto said its new dicamba formula would be less prone to drift but, across the US, neighbouring crops that are not dicamba-tolerant are being damaged by drift. This is leading many farmers to buy GM dicamba-tolerant seeds. See, for example, Latest Monsanto GMO seeds raises worries of monopoly, The Daily Mail, December 14, 2017

Glyphosate is a “probable human carcinogen”

The International Agency for Cancer Research (IARC) of the World Health Organization (WHO) has concluded that:

  • Glyphosate, the world’s most-used chemical ingredient for weed control, is a “probable human carcinogen” (March 2015)
  • 2,4-D, the second most-used herbicide in Canada, is a “possible human carcinogen” (June 2015)

Other Updates

October 2017: You can watch video of testimony at the European Parliament explaining the contents of internal emails dubbed the “Monsanto Papers” released by court order in the US.

April 2017: The Canadian Food Inspection Agency (CFIA) published the results of its testing of foods for glyphosate residues (2015-2016) The CFIA tested 3,188 food samples for the herbicide glyphosate. Glyphosate was found in 29.7% of samples. Glyphosate residues above MRLs were found in 1.3% of samples. (The majority of GM crops are genetically modified to be glyphosate-tolerant.)

April 2017: CBAN submitted comments to the Pesticide Management Regulatory Agency on the Cumulative Risk Assessment Framework, to raise the need to assess the impacts of GM herbicide-tolerant crops on herbicide use/exposure. Click here to read the comments from CBAN.

April 2017: Article – Big Agro on Campus: Universities claim industry-funded research on chemical and pesticide safety is scientifically sound. Not everybody is convinced, The Walrus.

October 2016: A review (monograph) on glyphosate from Pesticide Action Network Interantional

August 2015: An article in the New England Journal of Medicine argues that assessment of genetically modified food safety should also be tied to assessing the human health risks of the herbicides applied to GM crops. “We believe that the time has therefore come to thoroughly reconsider all aspects of the safety of plant biotechnology…The National Toxicology Program should urgently assess the toxicology of pure glyphosate, formulated glyphosate, and mixtures of glyphosate and other herbicides.”


The United Nations Food and Agriculture Organization reports that 21.9 million kilograms of herbicides were sold in Canada in 1994. Numbers from Health Canada’s annual reports show that by 2011, this number had increased by 130% to 50.3 million kilograms. By 2016, the number had increased by 199%.

The widespread cultivation of GM glyphosate-tolerant crops, in particular, has driven up the use of glyphosate-based herbicides. Glyphosate is the top pesticide ingredient sold in Canada, followed by 2,4-D and glufosinate ammonium. Glyphosate use in Canada tripled between 2005 and 2011, climbing from 30.2 million litres to 89.7 million in Western Canada, and from 3.8 million litres to 12.3 million in Eastern Canada.

This increased use of glyphosate has resulted in the emergence and spread of glyphosate-resistant weeds. In response, biotechnology companies have genetically engineered crops to be tolerant to the older herbicides 2,4-D and dicamba. These GM crops will further increase the herbicide load in the environment and lead to even more herbicide-resistant weeds.

GM insect-resistant (Bt) crops have reduced insecticide use in some countries. The Canadian government has not monitored the impact of Bt crops on insecticide use in Canada. However, insects are beginning to develop resistance to Bt crops in the US and other countries, and farmers are turning to other insecticide applications to control them. Additionally, Bt plants themselves produce insecticidal toxins that are released into the environment.

The use of herbicides with herbicide-tolerant crops reduces weed diversity in and around fields, which in turn reduces habitat and food for other important species, including the Monarch butterfly. Studies have also observed that GM insect-resistant crops can also have negative impacts on non-target insects, including pollinators, and soil and water organisms.

From Pesticides and Our Health, Greenpeace, 2015::

Synthetic pesticides have been widely used in industrial agriculture throughout the world since the 1950s. Over time, many of these chemicals have become extremely pervasive in our environment as a result of their widespread repeated use and, in some cases, their environmental persistence. Some take an extremely long time to degrade, such that even those banned decades ago, including DDT and its secondary products, are routinely found in the environment today.

As a consequence of this persistence, and potential hazards to wildlife, effect-related research on the impact of pesticides has increased exponentially over the past 30 years. It is now clear that these effects are wide and varied. Over the same period, scientific understanding of the effects of pesticides on human health and their mechanisms of action has also expanded rapidly, with studies revealing statistical associations between pesticide exposure and enhanced risks of developmental impairments, neurological and immune disorders and some cancers.

Nevertheless, proving definitively that exposure to a particular pesticide causes a disease or other condition in humans presents a considerable challenge. There are no groups in the human population that are completely unexposed to pesticides, and most diseases are multi-causal giving considerable complexity to public health assessments. Furthermore, most people are exposed to complex and ever changing mixtures of chemicals, not just pesticides, in their daily lives, through multiple routes of exposure. Pesticides contribute further to this toxic burden.


Pesticides and GM Crops

Pesticides and Pollinators

Hidden Costs of Toxic Seed Coatings: Insecticide Use on the Rise, Factsheet, Center for Food Safety, US, June 2015. Scientists have identified pesticides—specifically a group of insecticides called neonicotinoids (abbreviated as “neonics”)—as likely to be an important cause of declining pollinator populations and poor pollinator health. Neonics are the most widely used insecticides in the world, and have been repeatedly shown to have lethal and sub-lethal effects on beneficial insects.

Pesticide Toxicity

More Resources

Synthetic pesticides are not permitted for use in organic food production. Here is more information on the organic standard in Canada.

Organizations with up-to-date information on pesticide toxicity and related issues: