Glyphosate: As Safe As, Well, Poison

Years ago, Monsanto began touting its crown jewel weed killer, glyphosate (Roundup), as “less toxic to rats than table salt.” It was reminiscent of their infamous “DDT is good for me-e-e!” ads showing gleeful fruits and vegetables dancing around with a woman and cow. Now, after Roundup has been on the market for 40 years, a new review of the available data on glyphosate may alter the commonly held belief that it is benign.

The World Health Organization’s cancer research arm, the International Agency for Research on Cancer (IARC) put out an evaluation of glyphosate and four other herbicides and insecticides, which determined that glyphosate should be classified as a 2A carcinogen, meaning it is “probably carcinogenic to humans.” Just for a measure of comparison, the U.S. Environmental Protection Agency currently rates glyphosate at an E for carcinogenicity, indicating no risk of cancer whatsoever.

And in a wonderful illustration of the pot calling the kettle black, Monsanto responded to the report by denying that glyphosate could cause cancer in humans and accusing the IARC of using “cherry-picked” data, claiming that the agency had an “agenda-driven bias.”

Monsanto has a history of rejecting research pointing to negative impacts of glyphosate, like the late Andres Carrasco’s work in Argentina. Dr, Carrasco’s controversial 2010 study exposed frog and chicken embryos to dilutions of glyphosate and found that the treated embryos were “highly abnormal,” shedding light on possible interactions between glyphosate and developmental defects.

The rise of herbicide use in Argentina, specifically glyphosate, is being investigated as one major factor in the rise in cancer rates in towns adjacent to soybean fields. The province of Chaco’s Minister of Public Health has called for an independent health study to look at the links between agrochemicals and adverse health impacts in the community, such as birth defects.

So, why does this 2A distinction matter to you? Well, Roundup is the most commonly used herbicide in the U.S., with about 280 million pounds applied to crops in 2012—a ten-fold increase since 1996. Even if you don’t live near corn and soybean fields, you could be exposed to Roundup in the food you eat.

Most corn and soybeans that are sprayed with Roundup throughout the growing season mostly end up in processed foods or animal feed, but Monsanto’s GMO Roundup Ready sweet corn goes straight to the fresh market. The EPA sets tolerance levels on all foods sprayed with Roundup, but the U.S. Food & Drug Administration (FDA) has failed to ensure that foods aren’t sold with glyphosate residues higher than the regulated levels.

Without government accountability or labels on GMO foods, it is nearly impossible to make informed decisions to reduce exposure to this and other herbicides.

And to finish off the one-two punch against glyphosate, a different study published in mBio showed that the presence of glyphosate, 2,4-D or dicamba, at application levels recommended to farmers, can induce the ability for bacteria to develop resistance to antibiotics.

This study describes the interaction between antibiotics and herbicides and what that could mean for animal and human health. More research must be done in order to learn more about this mechanism and to what extent herbicides are driving the escalation of antibiotic resistance in agriculture, but for now its results indicate that our chemical-intensive agricultural system will only continue to negatively impact our health in myriad ways until we shift away from the excessive use of chemical inputs.

As Mark Bittman pointed out in his piece highlighting the IARC report, we don’t operate under the precautionary principle here in the U.S., instead “we ask not whether a given chemical might cause cancer but whether we’re certain that it does… But the job of the FDA should be to guarantee a reasonable expectation of protection from danger, not to wait until people become sick before taking products off the market.”

The IARC holds no regulatory authority, so for now, its evaluation stands on its own. This was made clear by the EPA’s decision, after the IARC announcement, to approve the use of Dow’s Enlist Duo mix of glyphosate and 2,4-D for nine additional states, bringing the total up to fifteen. EPA appears to be ignoring the international call to reevaluate the safety of this ubiquitous herbicide, gambling on new mixes of herbicides with unexplored synergistic effects instead.

It is time that the EPA consider the weight of the IARC’s work, change glyphosate’s carcinogenicity rank and conduct independent health assessments of the herbicide while it is undergoing a periodic review. And it is imperative that the FDA begins doing its job by monitoring glyphosate residues in food. Tell the EPA and FDA to meaningfully review and monitor glyphosate to protect your health immediately.