Glyphosate and cancer. This is something we are hearing so much about, seemingly all of the sudden, with major stories breaking in the last week. Just last Friday, a court case in California resulted in a $289 million dollar payment to a man named Dewayne Johnson, who claimed his years of using glyphosate (also known as Roundup) caused him to develop cancer. A few days before this story broke, glyphosate use was suspended by a judge in Brazil pending a government reevaluation of its toxicity.
What is going on here?
I am a farmer who uses glyphosate. My dad started using it decades ago, and it has absolutely been the single greatest invention in agricultural history. And it is unequivocally, fantastically safe. It is one of the lowest toxicity herbicides we use on our farm. It is less toxic than alcohol. Less toxic than caffeine. So what is all this about?
Why Do We Need It?
I am apart of a multi-generation family farm in southeast Saskatchewan, Canada. We grow canola, wheat, durum, peas, lentils, flax and soybeans, along with a few other crops. I farm with my sister, my mom and dad, my brother-in-law and my wife and two little boys. I love what I do.
In my part of the Canadian Prairies, we farm in some pretty dry conditions. Our average growing-season rainfall is about 9 inches, or 225 mm. Snow and fall rains provide us with another 4-5 inches. This is semi-arid agriculture, where the next rain really can provide the difference between profit and loss. So, we work very hard to use every drop of moisture we get. We have to. That means we cannot allow weeds to grow, and we must leave the soil undisturbed as much as possible – we do not want to till our land if we can at all avoid it.
What glyphosate allows us to do is to kill every weed in the field before the crop emerges. In the days before glyphosate, my grandfather had the very same goal – but he only had one way to do it. He had to work the land, over and over and over. The goal was to make it absolutely black. That was the only tool they had, and sadly, it was the direct cause of the great dust storms of the Dirty 30’s. Why would we ever want to go back to that?
Moreover, glyphosate allows us to control weeds in certain crops as they grow. Canola and soybeans are two crops I grow that are genetically engineered to be resistant to glyphosate. This means we can spray it over the crops, while they are young and struggle to compete with weeds, to keep them clean. We use different chemicals in other crops to accomplish the same thing, but none have the broad spectrum control that glyphosate has – and few of them are as cheap, or as safe.
The introduction of Roundup-Ready crops, including corn, soybean, canola, cotton and so on, has allowed for safe, simple, very cost-effective weed control.
Is It Safe?
This is the big question, and if you follow the news at all, I could certainly understand if you don’t feel it is safe. You may think it causes cancer, autism, and any number of diseases. That is what you’ll find on the Internet.
Here’s the experience of a farmer.
I use glyphosate hundreds of hours every year. I load and run our sprayers (along with farm employees and my family) over thousands and thousands of acres spraying glyphosate. My son rides in the sprayer with me sometimes. And I don’t worry at all about glyphosate being dangerous.
Here’s the thing about spraying a chemical like glyphosate. An acre of land is 43,560 square feet, which is a little smaller than an American football field. On that acre, 360 grams of glyphosate active ingredient is sprayed. Put another way: 2 cans of beer of glyphosate sprayed over an area almost the size of a football field. That’s .015 mL of beer on each square foot – and that includes the solution the glyphosate active ingredient is suspended in. That is an incredibly low concentration. A standard “drop” of water is .05 mL. That’s less than a third of a drop of water!
Sure, some chemicals are highly toxic in even very small doses. Glyphosate is not one of those chemicals. Its LD50, or the lethal dose for 50% of rats in testing, is 5,600 mg/kg. The LD50 for caffeine? 192 mg/kg. Don’t panic about your coffee though – that’s still very safe!
Does Glyphosate Cause Cancer?
While I have explained that an acute dose of glyphosate is safe, that doesn’t really answer the cancer question. That is something that would accrue over many years, and may have little to do with the aforementioned LD50. Has this been studied thoroughly enough to be sure glyphosate is indeed safe? And has it been studied by independent organizations and scientists?
John Giesy, a professor and research chair in environmental toxicology at the University of Saskatchewan, would argue that yes, glyphosate is safe. He has quite the resume, as a professor or honorary professor at six other universities and is the most cited author in the world in the combined fields of ecology and environmental sciences. In an article you can find here, when speaking about the subject of cancer, he had this to say:
“Certainly you wouldn’t wish it on anyone. But whether it’s caused by glyphosate, in my opinion, is highly unlikely.”
In 2015, the International Agency for Research on Cancer (IARC), a WHO agency, claimed that glyphosate was a “probable carcinogen”. Glyphosate is hardly alone in this category, with such partners as high temperature frying, working as a hairdresser, red meat or shiftwork. Stuff that is actually carcinogenic on their list? Alcoholic beverages, sawdust and processed meat (to name a few). Yes, beer and hot dogs are considered more likely to cause cancer than glyphosate (source).
It was this IARC report that started all of this, and there are some real questions as to their methodology. In fact, according to the then- European Crop Protection Director, General Jean-Charles Bocquet,
“From the summary conclusions it appears that IARC has made its conclusions as a result of an incomplete data review that has omitted key evidence.” (source)
It was recently discovered that the IARC had removed findings from studies that concluded glyphosate was not a carcinogen before they published the final version. They also used the infamous, now retracted Seralini rat study in their analysis.
The fact is that numerous organizations conclude glyphosate is safe, including the UN’s Food and Agriculture Organization, the European Food Safety Administration, Health Canada, the German Risk Agency, and on and on. A massive study run on 89,000 farmers and their familes in Iowa and North Carolina since 1993 has failed to find any link between glyphosate and cancer. How much more evidence do we need?
I need glyphosate on my farm. It helps me be more sustainable, both environmentally and economically, it helps me protect my soil from erosion and build soil health, and it helps me sequester carbon, reducing greenhouse gas emissions. The fear over glyphosate is unfounded, and we need to slow down and have a real discussion about it. If you want to come to my farm and see how we use this contentious chemical, please let me know. My door is open for anyone who wants to have their questions answered.