Glyphosate weed killers like Roundup should be banned in Canada and around the world

Farmers around the world all need to deal with weeds. The most widely used chemical product they use to kill those unwanted plants is glyphosate, often sold under commercial names like Roundup.

In 2015, the World Health Organization declared glyphosate a “Probable Human Carcinogen.” This link to cancer was reinforced in January 2024 when a jury in the United States concluded Roundup caused non-Hodgkin’s lymphoma and ordered chemical company Bayer — which purchased Roundup producer Monsanto in 2018 — to pay US$2.5 billion in damages. Bayer has announced it intends to appeal the verdict.

Scientists have also raised concerns about the environmental harms of long-term glyphosate application. To name just a few, glyphosate threatens honey bee populations and has been found to kill birds, fish and soil microorganisms, all of which are crucial for ecosystem health.

In the face of these concerns, some governments have restricted or even banned glyphosate application, though no such ban is in place in Canada.

Banning glyphosate is an essential step in protecting the health of humans and our ecosystems. Until a full ban is achieved, however, the pioneering work of farmers in Mexico shows how agroecological techniques can replace these chemical interventions.

Toxic exports

In April 2024, Mexico was set to become the largest jurisdiction to enact a total ban on glyphosate. However, just before the ban came into effect the government announced a pause.

Officials cited concerns about a lack of viable substitutes, but critics believe the waffling has more to do with intense lobbying by agro-industry, including heavy pressure from the U.S. – the main exporter of glyphosate to Mexico.

Monsanto, a major glyphosate exporter, has been shown to have influenced academic research to downplay the health risks of its valuable product.

In the northern region of Mexico’s Veracruz State, we are working with small-scale citrus farmers to help them transition away from glyphosate (and other agrochemicals) by supporting adoption of agroecological farming methods.

Our research shows that agroecological farming is a viable alternative and, with a little bit of support, large numbers of farmers are keen to make change.

Scaling up agroecology

The farmers we work with are abandoning glyphosate one hectare at a time. With funding from Mexico’s National Research Council, we have built a team of 38 agroecology technicians and community leaders who are helping farmers develop the knowledge and skills they need to replace chemicals with other practices.

Our team supports farmers to plant legume cover crops to crowd out weeds, and we have provided thousands of weed whackers to make manual weed control quicker and easier. We are also teaching farmers to make their own products from inexpensive local materials, like agua de vidrio — a solution of ash and lime — that provides nutrients to plants and helps control pests and diseases.

Part of what makes this work successful is that we are leading by example, using the Gómez family citrus farm as a living classroom. That farm used to produce conventional oranges. Then, in 2004, the family transitioned one hectare to organic production as an experiment. By 2012, the entire 16-hectare farm had transitioned away from agrochemical use and was certified as organic.

Since then, the Gómez’s have implemented a wide range of agroecological practices on the farm. They also created an outdoor classroom space and an area dedicated to producing compost and other ecological inputs.

In 2018 almost 1,000 people visited the farm — dubbed Huerta Madre, or Mother Farm by locals — to learn about agroecological methods. Thanks to government funding, in 2023 the number of visitors jumped to more than 2,500. The funding also enabled researchers and technicians to connect with more than 10,000 farmers across the region, sharing information about the potential dangers of glyphosate and the viability of agroecological alternatives.

Of those 10,000 farmers, 3,600 are now actively working with our team to stop using glyphosate and implement agroecological alternatives.

Reaching this number of farmers has been possible in part because the current Mexican government has made it clear that agroecology is a priority. While agroecological farming has long been championed by “peasant organizations” and social movements, political support of the kind happening in Mexico today has been harder to come by (although there are some notable exceptions).

Presidential decree

A cornerstone of Mexico’s pro-agroecology policy was a 2020 decree by President Andrés Manuel López Obrador that the country would eliminate glyphosate use by January 2024. The decree was immediately criticized by the United States Department of Agriculture (USDA). It was also contested — including via legal challenges — by Mexican agri-business interests, primarily in the country’s north where large-scale conventional farming dominates the landscape.

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In February 2023, Obrador postponed the date of the ban to April 1, 2024. Then, just days before it was to come into effect, the government announced the ban would be paused. Advocates of the ban reacted with formal protest letters, media interviews and social media posts. They highlighted how research and practice has demonstrated the viability of an array of glyphosate alternatives, including the scaling up of agroecology amongst citrus farmers in Veracruz.

To date, the ban remains on hold, and it is unclear what incoming President Claudia Sheinbaum will do about it.

Will we ever see a glyphosate ban?

Mexico is not the first country to waver on a glyphosate ban. Sri Lanka imposed a ban in 2015 but lifted it by 2022. In the European Union, several member states have been vocal in their desire for a ban, but glyphosate was re-authorized for a ten-year period in December 2023.

While the reasons may be complex, it is clear that stemming the tide of glyphosate is challenging, even when there is significant political will. This is likely at least in part due to the significant lobbying power of companies like Bayer.

Even if a formal ban remains out of reach, Obrador’s decree created an important opening for agroecology in Mexico. While some initiatives have existed for decades, especially in the southern states of Oaxaca and Chiapas, government support has sparked development of many more.

The presidential decree also enabled unusually high levels of investment into agroecological research and development. Coupled with other pro-agroecology policies, the decree has created momentum for scaling up agroecology across the country. The thousands of citrus farmers who are finding success without glyphosate in Veracruz can attest to that.

The authors’ research was conducted with the support of research assistant Luis Enrique Ortiz-Martínez.