Understanding Glyphosate Toxicity: An Interview with Genetic Engineer Thierry Vrain

As genetically modified organisms (GMOs) continue to enter the food chain, it’s important for consumers to learn about Roundup Ready crops — and how the glyphosate sprayed on them may be toxic to our health.

| June/July 2016

Glyphosate toxicity

A high-clearance sprayer applies Roundup herbicide on glyphosate-resistant marestail in a Mississippi no-till cotton field. The application failed and the weeds survived.

Photo by AgStock Images

Monsanto’s Roundup Ready crops are engineered to be herbicide tolerant, specifically when sprayed with Roundup. Now that the World Health Organization’s cancer research arm has designated Roundup’s active ingredient, glyphosate, as “probably carcinogenic to humans,” consumers need to fully understand how the chemical works on plants and, in turn, impacts human health. For in-depth answers about glyphosate’s toxicity and more, we turned to molecular biologist and retired genetic engineer Thierry Vrain.

MOTHER: When and why did you start researching glyphosate?

Thierry Vrain: I went to graduate school in North Carolina in the 1970s, where I was trained as a soil biologist — a nematologist, to be precise. Nematodes are microscopic worms in the soil that feed on the roots of plants and cause considerable yield loss for many types of crops. In school, I learned about agriculture and the damage caused by all sorts of pests and pathogens, such as nematodes, insects, and fungal diseases. I learned to deal with those pests by sterilizing soil or spraying pesticides. Halfway through my career, it became obvious that perhaps we could intervene at the molecular level to make crops naturally resistant to pests, so I learned molecular biology and became a genetic engineer. When I became head of a molecular biology department, I took it as my responsibility to educate people and try to assuage their fears about genetic engineering.

I retired 12 years ago and started gardening as a serious hobby. After gaining that hands-on experience, I realized how much damage pesticides cause to the living environment of the soil. I learned all sorts of things that I wasn’t taught in graduate school. For example, I learned that not only pesticides, but also regular fertilizers damage communities of microorganisms in soil. I became “organic,” so to speak.

At this point, I started reading scientific research showing a problem with genetic engineering. Rats and mice fed genetically engineered, Roundup Ready grain were getting sick. At first I couldn’t figure it out. My knowledge of the engineering technology made it clear to me that this should be safe. As I explain in my TEDx talk, “The Gene Revolution, the Future of Agriculture,” I couldn’t understand why adding a gene from one species to another could be toxic because this DNA technology is used every day in many research labs around the world to create a variety of transgenic animals and plants, to study their biology, and to advance various fields of knowledge. Only two years ago did I realize that the problem lies not with genetic engineering technology itself, but with the herbicide that’s sprayed on all Roundup Ready crops. Again, I took it as my responsibility to educate people.

MOTHER: When was this herbicide invented, and for what purpose?

6/11/2016 8:03:44 PM

Thank you for the timely interview with Dr. Vrain. I have been suspecting for some time that it is NOT the GMO side of food manipulation, but rather the fact it allows us to spray glyphosate, which in turn is kill our important natural gut flora. How many people are gluten intolerant, suffer from crones or irritable bowel syndrome as a result of ingesting glyphosate? Is it reversible? Let's hope so!

mother earth news fair


Oct. 21-22, 2017
Topeka, KS.

More than 150 workshops, great deals from more than 200 exhibitors, off-stage demos, inspirational keynotes, and great food!