Bayer Forges Ahead with New Crops Resistant to 5 Herbicides | Civil Eats

Bayer Forges Ahead with New Crops Resistant to 5 Herbicides

Despite lawsuits and regulations, the agrichemical company is developing new genetically engineered corn designed to work with five herbicides, including glyphosate and dicamba.

a farmer walks in a cornfield contemplating whether to spray glyphosate, dicamba, or one of three other herbicides in a new corn variety proposed by Bayer/Monsanto

Over the past few years, Bayer (which now owns Monsanto) has repeatedly lost in court to those who have claimed its Roundup herbicide is responsible for their cancer diagnoses. Things appeared to get worse for the agrichemical company last week, when it agreed to pay $10 billion to settle tens of thousands of similar lawsuits.

At the same time, the company paid $400 million to settle claims brought by farmers who claimed their crops were destroyed when dicamba, the active ingredient in Bayer’s XtendiMax herbicide, drifted onto their fields. That was after a federal court reversed the U.S. Environmental Protection Agency’s (EPA) approval of dicamba based on extensive evidence of widespread harm it caused to farmers’ crops. (U.S. Secretary of Agriculture Sonny Perdue then urged the EPA to allow the continued use of already purchased dicamba products.)

Public health advocates and environmental groups have celebrated these news stories as victories in their crusade to reduce the widespread use of genetic engineering (GE) and hazardous pesticides. Meanwhile, it appears that Bayer has barely registered them as speed bumps, as the company forges ahead with new products that are likely to increase the use of the very same—and additional—herbicides.

“Bayer is committed to and stands fully behind our Roundup and XtendiMax herbicides. We are proud of our role in bringing solutions to help growers safely, successfully, and sustainably protect their crops from weeds,” a Bayer spokesperson told Civil Eats.

And in fact, the U.S. Department of Agriculture (USDA) is currently considering the approval of a genetically engineered variety of corn developed by Bayer that would be resistant to at least five herbicides at once—including glyphosate (the active ingredient in Roundup) and dicamba.

If all goes according to plan, the company expects to launch the corn in the U.S. “mid-to-late this decade.” Some groups hope to disrupt that trajectory.

“The fact that Bayer is now petitioning for this new GE maize shows that it has certainly not shifted the corporation’s intentions with respect to how to get on the right side of history . . . or to back off from a production system that is going to lock farmers into a chemical-intensive business model,” said Marcia Ishii-Eiteman, a senior scientist at the Pesticide Action Network (PAN), which is urging its members to comment on the USDA petition for the seed’s approval. “They are just pushing forward.”

Chemical-Resistant Corn

The new variety of corn, MON 87429, would be bred with other hybrid varieties to produce seeds that, when planted, will grow despite being sprayed by glyphosate, dicamba, 2,4-D, quizalofop, and glufosinate.

Bill Freese, a science policy analyst at the Center for Food Safety, said that while a crop that is resistant to five herbicides is “certainly a record,” it’s not a surprising next step for the industry, which has been increasingly introducing multi-herbicide-resistant varieties.

The new variety of corn will grow despite being sprayed by glyphosate, dicamba, 2,4-D, quizalofop, and glufosinate.

Corteva’s Enlist corn is resistant to both glyphosate and 2,4-D, while Bayer’s Xtend system includes soybean and cotton varieties resistant to glyphosate and dicamba. Its newest XtendFlex soybeans are resistant to glyphosate, dicamba, and glufosinate.

Most herbicides only kill certain classes of weeds; Roundup is designed to kill nearly everything. But after decades of intensive, widespread use, many weeds have developed resistance to glyphosate, leaving farmers who have come to rely on Roundup in need of additional chemicals for weed management.

“It’s the logical progression, to make everything resistant to most major classes of herbicides,” Freese said. “What’s important, in our view, is that extremely troubling trend in industrial agriculture, which leads to much greater, more intensive herbicide use and more weeds resistant to multiple herbicides.”

Bayer submitted a petition requesting “nonregulated” status for MON 87429 last year, which essentially means it wants to move the crop out of field trials and into commercial use. If the USDA grants that status, Bayer will be able to plant and breed the crop free of regulation. In May, the USDA posted the company’s petition in the federal register, where it is open for public comment until July 7. After that, the agency will conduct an assessment of the petition and determine whether it plans to grant nonregulated status. When that assessment is complete, USDA will open up another public comment period.

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Based on recent history, experts say the USDA is likely on track to approve the variety. (The agency also recently further relaxed its rules related to GE regulation, but this seed is being evaluated under the old rules.) And because the plants themselves won’t produce pesticides (unlike GE crops such as BT corn, which produce insecticides within the plant), the seed does not have to be approved by the EPA.

Effects of Modifying Crops for Herbicide Use

The EPA does regulate the herbicides that will then be used on the new corn variety, but it already considers these chemicals to be safe and allows their use.

For example, an EPA assessment released in January concluded that glyphosate is not a human carcinogen, although the International Agency for Research on Cancer has linked it to cancer and calls it a probable carcinogen. Meanwhile, numerous court juries have sided with scientists who presented evidence showing glyphosate is associated with non-Hodgkin’s lymphoma. (Part of Bayer’s recent settlement will be used to set up an independent expert panel to definitively tackle whether the chemical causes cancer and, if so, to determine what level of exposure is dangerous.)

In addition to destroying nearby farmers’ crops, dicamba has destroyed tens of millions of trees across the country, devastating orchards and ecosystems. 2,4-D is an older herbicide that has also been linked to serious health risks including non-Hodgkin’s lymphoma and thyroid disorders; its effects on ecosystems and wildlife were documented as early as the 1960s, in Rachel Carson’s Silent Spring.

One of the biggest concerns around introducing new herbicide-resistant crops is that they will likely lead to a significantly increase in the volume of herbicides farmers apply.

Quizalofop, an herbicide that kills grassy weeds and is currently used on some wheat, has been linked to reproductive cancers and liver toxicity, but is considered safe at current use levels by the EPA. More research on glufosinate’s health and environmental effects is needed; researchers have determined it is not carcinogenic, but the European Union classifies it with a warning for organ toxicity and negative effects on fertility and fetal development.

One of the biggest concerns around introducing new herbicide-resistant crops is that they will likely lead to a significantly increase in the volume of herbicides farmers apply. One analysis found that since Roundup-ready crops were introduced in the mid 1990s, global use of glyphosate has increased 15-fold. In the U.S., Bayer’s dicamba-resistant Xtend system skyrocketed in popularity after 2016; between 2016 and 2017, estimated dicamba use doubled, from less than 10 million pounds to close to 20 million.

Another concern is a lack of data on the effects of using so many different herbicides on the same plants, landscape, and food, and what exposure to that combination might mean for farmers and farmworkers.

“We don’t know what the synergistic effects of these cocktails of pesticides will be when applied,” Ishii-Eiteman said, referring to the potential for unexpected effects when two chemicals interact. And yet, state and federal regulators generally focus on the effects of each chemical used on its own. There is some evidence that pesticides can have cumulative effects, in terms of a build-up of exposures, but the impact is very hard to measure.

Bayer’s spokesperson said that the crop’s intention would be to give farmers the flexibility to choose between herbicides, and that the company did not expect farmers to apply all five herbicides to the same crop.

Advocates have also expressed concerns about increased herbicide use exacerbating the current problem with herbicide-resistant weeds. Because Roundup can be applied liberally to destroy almost any weed, its widespread use has reduced its efficacy. According to the USDA, 14 glyphosate-resistant weeds currently plague U.S. cropland, and one 2013 study found 50 percent of farms surveyed were dealing with these powerful plants.

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Bayer acknowledges the issue in its petition, writing that, “MON 87429 maize will offer growers multiple choices for effective weed management, including tough-to-control and herbicide-resistant broadleaf and grass weeds” and specifically pointing out that “dicamba, glufosinate, and 2,4-D individually or in certain combinations provide control of” certain glyphosate-resistant weeds.”

Their scientists and other researchers and organizations, including at the USDA, point to the fact that combining or alternating herbicides has been found to reduce the development of herbicide resistance compared to relying on single herbicides.

However, that’s the logic that Bayer applied when adding dicamba to glyphosate in its Xtend system, and the scaled-up planting of those crops created dicamba-resistant palmer amaranth in just a few years.

Rob Faux operates a diversified organic farm that’s surrounded by commodity fields in Northeast Iowa, and he said he doesn’t buy into the company’s stated goal of providing farmers with more options. “In reality, they’re trying to reduce the choices farmers have,” Faux, who also runs Iowa communications for PAN, told Civil Eats. “They’re not trying to provide more tools for the farmer. They’re just trying to capture market. And unfortunately, some of that market they’ll capture is by causing people to plant these seeds defensively.”

Faux was referring to farmers he knows in Iowa who have planted dicamba-resistant seeds to preemptively protect their crops from plumes of drift that float through the air from neighboring farms, even if they did not plan on using the herbicide themselves.

Now that a federal court has recognized the issue of drift as significant enough to ban the herbicide, the future of dicamba is uncertain. On June 16, Bayer announced it was scrapping a billion-dollar project to produce the herbicide in the U.S., but said it was unrelated to the court decision. And many other signs point to the company moving full-speed ahead. In addition to MON 87429, a Bayer spokesperson told Politico this week that the company also has “several dicamba formulations in our pipeline.”

Lisa Held is Civil Eats’ senior staff reporter and contributing editor. Since 2015, she has reported on agriculture and the food system with an eye toward sustainability, equality, and health, and her stories have appeared in publications including The Guardian, The Washington Post, and Mother Jones. In the past, she covered health and wellness and was an editor at Well+Good. She is based in Baltimore and has a master's degree from Columbia University's School of Journalism. Read more >

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  1. Denise
    " Fools rush in where angels fear to tread"
    Immoral agrichemical corps need regulations
  2. Axel
    If we are going to feed 10 billion people we need to use fertilizers pest and herbicides and GMOs. If we were to only farm "ecologically" there would not be any land left for wild life we already use 37%. Also the study showing glyphosate exposure cause an increased risk in non-hodgkins lymfom is a meta analysis which conveniently left out studies showing no link, I think the IRAC report is highly suspect .
    Chemicals should be regulated and tested thoroughly, however the pesticide and GMO scare is highly unscientific, and have probably caused many deaths in developing countries.
    • William Brooks
      The 125,000 farmers who exclusively used roundup, were faking their cancer?
    • Carmen I Ortiz
      What a briliant idea! We feed 10 billion people chemical based fertilizers, herbicides and GMO and solve the population problem! Only problem we also kill all living organisms and then who will buy Bayer products. Highly suspect is someone like our pal Axel. Note he did not include last name, where as I did. Why are you trying to hide your identity, if you are so sure of what you claim. Surprise you didn't call yourself "farmer", "son of farmer", etc, the names my "friend" from Monsanto used to hide the fact that he was the same person. Who also pretended he was a "survivalist", while writing the same script uder all those names. I'm old, I don't forget.

      "Chemicals should be regulated and tested?" Why, you already concluded "the pesticide and GMO scare is highly unscientific", while admitting "probably caused many deaths in developing countries". Change it to "surely" and we have an agreement. What do you care, as long as you are not the one dead. Ask India, and much of Africa, what they think about the "chemical based fertilizers, herbicides and GMO", they were fooled into using by Monsanto and Billy G the billionaire (share holder). While you are at it, asked them what happened to the soil, where those "safe chemicals" were sprayed. Oh, wait, I forgot, many of them committed suicide after what little they had was destroyed. Bayer absorbed Monsanto and added even more. And somehow, the fairy godmother came and made them all safe for humans and other organisms.
    • Tai Lahans
      Yes. You're right. GMO and the unsustainable practice of using herbicides and pesticides has caused many many deaths in developing and and in developed countries. Just look at the rate for cancer death in 1900 = 4%, in 1970 = 20%, in 2000 = 30%. There is no place on Earth where these chemicals are not present. A truly sad legacy made for and by humans that ends in death for the Earth itself, our home.
  3. Heather
    This is terrible news....Bayer must not be allowed to continue with this chemical warfare on the human race.
  4. Mike Foxworth
    Our politics and the economics of large field crop production has driven us to this unsustainable state. Historically crop rotation has been the main tool to slow genetic adaptation of non-desired plants. In many parts of the world it still is. Human population is shifting to a steadily decelerating growth path. Genetic modification (a technical extension of classic crop domestication) will have an important supporting role in balancing population growth and food consumption. In our current situation, those vital genetic modification tools have been harnessed to a disastrous spiral of ecological damage.
    The huge, costly, and highly specialized machines used in much of the industry are only viable when used every year and with minimum transportation costs. As a result, control of non-desired species via crop rotation has been driven off the table for much of the US and, increasingly, in many other countries. Planting the same crops with little or no genetic diversity in every field, every year makes a perfect environment to encourage plants to adapt. Just as urban living allows new diseases to spread quickly in human populations.
    The resulting "arms race" between plants and science with no crop rotation means any anti-plant chemical or seed innovation only has a few years, at most, before plant adaptation makes it economically useless. So the developing company needs to drive demand for the product up quickly to recoup development costs. Linking seed and herbicide development together (as in dicambia and MON 87429 corn) is a way to preserve a longer window to recoup costs. Monsanto and Bayer are simply working within the rules of the political game our society has put them in.
    American and worldwide farmers see themselves as independent actors authorized to make decisions without regard to external effects of those decisions. There is inherent good in that attitude - individual farmers are not in a position to evaluate those external effects or protect themselves from the economic consequences of extraordinary efforts to prevent that harm to others.
    In societies, we have governments and rules to constrain independent actors to stay within boundaries. The rules direct the independent actors into constructive paths. Our two intellectually bankrupt parties have created a situation that persuaded its fed up citizens to elect charlatans like Trump. Who, in turn, has unleashed the robbers to mind the store.
  5. Mary Ann Prosyniuk
    I’m quite certain that the number of US citizens that know of the Federal Register and it’s role in our self-governing is minuscule.
    Please provide education and links for us to make direct comments, so we may have a more active, direct involvement in such issues that impact each of us.
    Thank you!

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