What the IARC 2A Rating for Glyphosate Really Means

What the IARC 2A Rating for Glyphosate Really Means

By Donna Farmer,
Product Protection & Nutrition Lead

As a toxicologist who has dedicated the better part of my 30-year career to product safety, it feels important to explain what the recent IARC review means – and doesn’t mean.

The International Agency for Research on Cancer (IARC) convened a meeting March 3-10, 2015 to evaluate the potential carcinogenic risks to humans from several pesticides, including glyphosate. Glyphosate is an active ingredient in many popular herbicides, including some produced by Monsanto.

IARC concluded that glyphosate belongs in a 2A category as probably carcinogenic to humans, a category that includes professions such as barbers and fry cooks. It is extremely disconcerting that IARC’s conclusion conflicts with the overwhelming consensus by regulatory bodies and science organizations around the world like the U.S. EPA, which concluded that there is evidence of non-carcinogenicity.

In fact, glyphosate and glyphosate-based herbicides are among the most thoroughly tested and evaluated pesticide products in the world. Their 40-year history of safe use is supported by one of the most extensive worldwide human health, crop residue and environmental databases ever compiled on any pesticide.


IARC, however, did not base its decision on all this evidence. Instead IARC disregarded dozens of scientific studies and relied heavily on papers that created false associations.

IARC drew conclusions based on a limited data review debated during a one-week meeting. This process is in stark contrast to periodic regulatory reviews. For example, the regulators in the United States and Canada began reviews of glyphosate in 2009 and should conclude more than five years later, in 2015.

It’s also important to note that all glyphosate-based herbicides on the market today must meet rigorous standards of approval set by regulatory and health authorities to protect the public, including infants and children. Most recently, the German Federal Institute for Risk Assessment released its decision on behalf of the European Union, concluding, after a four-year review, that there is no cause-and-effect link between glyphosate exposure and cancer.

Safeguarding human health and the environment is critical to Monsanto’s business and critical to each of us on a personal level. We are moms, dads, sisters and brothers and as such, we’re caretakers of each other as well as our planet. Consumers can be confident in the safety of our Roundup® brand herbicides because there are more than three decades of independent scientific evaluations indicating that all approved uses of glyphosate are safe for humans and the environment.

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Summaries of recent cancer studies reaffirm glyphosate does not cause cancer in humans or animals.