The Glyphosate Debate: Examining the Controversy Surrounding the World's Most Used Herbicide

Chelsea Newbrough, RDN

Last weekend I found myself deep in the trenches of glyphosate research, as one does on their Saturday morning. Before I had finished my first cup of coffee, I was down the rabbit hole, and I was there to stay. It wasn't the topic I had in mind for this week, but I pretty soon realized how complex of an issue it is, and how it may serve as an important reminder of how critical it is to look at the entire picture.

Glyphosate, the active ingredient in the widely used herbicide Roundup, is one of the latest buzzwords but has actually been at the center of a heated debate for years. Praised by some as a crucial tool in modern agriculture and vilified by others as a potential health and environmental hazard, glyphosate's story is one of complex scientific research, regulatory battles, and deeply entrenched interests. I wanted to delve into the controversy surrounding glyphosate, examining its uses, potential risks, and the broader implications for public health.

A Note on Toxins

Before I dig in here, if there is no other takeaway from this article, you must understand that toxins are a part of everyday life and cannot be, and should not be, entirely irradicated. "Toxins" is a buzzword in itself, especially in the functional medicine space, and there are plenty of the extreme "practitioners" out there that looooove fear mongering (mainly to sell their own shit). Toxins exist, we have systems in place to protect ourselves from them, but understandably we also don't want an unnecessary level of exposure that may lead to adverse health outcomes.

Understanding Glyphosate 

Glyphosate, discovered in the 1970s by the multinational agrochemical corporation Monsanto (now owned by Bayer), is a broad-spectrum herbicide that effectively kills weeds by inhibiting a crucial enzyme involved in plant growth.

The vast majority of genetically modified crops (GMO's) have been produced to be resistant to the effects of glyphosate making it extremely effective. That along with its relatively low cost have made it one of the most widely used herbicides globally, employed in agriculture, forestry, urban landscaping, and home gardening.

The Controversy

The controversy surrounding glyphosate primarily revolves around two main issues: its potential health effects on humans and wildlife, and its impact on the environment. While I am a tree hugging animal lover, for the sake of this article, I'm only going to dive into the health risks to humans.

Health Concerns

Numerous studies have explored the potential health risks associated with glyphosate exposure, with conflicting results adding to the complexity of the debate. While some studies suggest a link between glyphosate and various health issues, in particular non-Hodgkin Lymphoma (NHL), others argue that the evidence is inconclusive or insufficient to establish a definitive causal relationship.

The International Agency for Research on Cancer (IARC), a branch of the World Health Organization (WHO), classified glyphosate as "probably carcinogenic to humans" in 2015, sparking significant controversy and legal battles.

However, regulatory agencies including the Environmental Protection Agency (EPA) have since largely concluded that glyphosate is unlikely to pose a carcinogenic risk to humans when used according to approved guidelines. A 2021 meta-analysis also concluded that the evidence was insufficient that exposure to glyphosate increased the risk of NHL specifically but noted it could not rule out a possible association with diffuse large B-cell lymphoma (DLBCL).

So how does there come to be such a disagreement between known and respected organizations? While some will suggest that IARC only used a handful of animal studies, i.e. weak research, to come to their conclusion, IARC cites 269 references in their published monograph. They also note that in the interest of transparency, they rely only on data that are in the public domain and available for independent scientific review. They also note that many regulatory agencies rely primarily on industry data from toxicological studies that are not available in the public domain.

Take from that what you will.

Safe Limits

"The dose makes the poison" is the most basic principle of toxicology, but what if there's conflicting information on what that dose is? The EPA has established the highest "safe limits" for crops that range from 0.1-400 parts per million (ppm). The Environmental Working Group (EWG) reports a safe limit of 160ppb. California has much tighter regulations, setting the limit at 1100ug/day. Not confusing at all.

Glyphosate Containing Foods

Glyphosate is primarily found in beans, legumes, oats, grains, and cereals grown with traditional (non-organic) farming techniques.  In 2018, the EWG tested several popular brands of oat-based cereals and snacks and found 35 of the 48 products tested contained glyphosate levels above their safe limit of 160ppb. Honey Nut Cheerios samples came back at 833 and 894ppb respectively, which sparked the debate about the safety of this popular breakfast cereal. This wasn't the worst offender unfortunately, with Quaker Honey Nut Oatmeal Squares coming in at a staggering 2837ppb.

In 2022 the EWG repeated a test on 17 of the oat-based products plus 17 additional baby food products and found that overall levels of glyphosate had dropped dramatically. The majority of the baby food tested, both organic and non-organic, did not have any detectable glyphosate. Of the few that did, the levels were very low, and none exceeded the recommended safe limit. A total of 6 of the other 17 products tested came back with levels above the 160ppb, however most were in the 200's and the highest came back at 482.9ppb. Honey Nut Cheerios samples came back at 111.6 and 161.4ppb this time around. It is worth noting that the amount sometimes varied much more drastically from one sample to another of some of the other products.

These findings suggest that public concern has influenced the usage of glyphosate in farming practices but confirms that it is still prevalent in use.

How Do I Avoid Exposure? 

With conclusions on the safety of glyphosate mixed, it is understandable that some may want to err on the side of caution. Here are the best ways to limit your exposure to glyphosate:

1. Buy organic: While there are no guarantees that there will be absolutely zero glyphosate, it isn't used in organic farming practices. Contamination from other sources is likely low, if any.

2. Look for non-GMO: Most GMO crops are resistant to glyphosate, so looking for non-GMO labels is one way to lessen your chances of heavy exposure. While this label usually goes hand in hand with most organic products, not all non-GMO foods are organic.

3. Wash your produce: Depending on the level of contamination, washing may not get rid of glyphosate entirely, but it can help. Washing your product is the most cost-effective way to reduce overall pesticide consumption, so it's a good practice regardless of your opinion on glyphosate specifically.

4. Grow your own: Have a green thumb? Growing your own produce at home is one sure-fire way to know what it has been exposed to.

5. Support activism: Consumers drive companies to take action. Do what you can to support initiatives for improved farming practices.

Key Considerations

While it is easy to suggest that glyphosate be banned outright, we cannot do so without a viable alternative. Pesticides allow farmers to grow a large quantity of crops that helps keep prices low for consumers. Organic farming is expensive, and although it should be supported and encouraged, not everyone can put their food dollars to the cause.

Glyphosate concentrations in crops seem to be trending downward, and I would argue against continuing to shun popular cereals based off of 2018 data, when newer data has since emerged.

More research is needed to make definitive claims on the safety of glyphosate, but there is enough out there to suggest we should approach with caution. While the debate over glyphosate's safety and environmental impact remains far from settled, it serves as a key reminder of the complex challenges inherent in balancing agricultural productivity, human health, and environmental sustainability in the modern world.