The Poison Is in the Dose

One of the most controversial pesticides in use today is glyphosate, also known by its trade name, Roundup. Its original manufacturer, Missouri-based Monsanto, which was acquired by the multinational biotech company Bayer in 2018, developed an interest in herbicides during the 1960s.

They were one of the major manufacturers of Agent Orange, a defoliant widely used during the Vietnam War to eliminate cover for the Viet Cong, which the US Army was fighting. (Scientists raised concerns about Agent Orange as early as 1965; it was later proved to cause severe health impacts, including birth defects and cancer. One of the ingredients in Agent Orange, 2,4-D, is still widely used as an herbicide in the United States, including in common lawn care products.)

After the war, Monsanto developed Roundup, which it advertised as a safer alternative to other herbicides. Glyphosate kills plants by inhibiting an enzyme plants use to produce energy. While humans don’t have this enzyme, some research has found it shares pathways with our gut bacteria, disrupting our microbiome. This can lead to inflammation and oxidative stress, damaging cellular DNA.

Over time, this damage can accumulate, triggering mutations that cause cancer. Even at very low exposure levels, glyphosate can disrupt the endocrine system, accelerating tumor growth.

By the 1990s, Monsanto started selling genetically modified seeds so that farmers could spray Roundup over crops, and only the weeds would die. As far as pesticide toxicity goes, says Lori Ann Burd, environmental health program director at the nonprofit Center for Biological Diversity, glyphosate is far from the worst. But she adds the poison is in the size of the dose. “We developed a whole system of agriculture around Roundup-ready crops,” Burd says, “and because of that, we use such an outrageously massive amount of it that it is causing such huge harm.”

Glyphosate is now the most commonly used pesticide in the country, with an $10 billion global market. It’s been detected in unsafe levels in rainwater and pregnant women with no known exposure. And like Agent Orange, Monsanto has for many years publicly denied the associated risks — even though the company’s internal documents show it had reason to believe glyphosate is dangerous since at least 1983.

In a 2021 study, Glenna at Penn State found that Monsanto, now owned by Bayer, previously attempted to manipulate the scientific peer-review process. He documented the company’s efforts using internal emails released during a lawsuit, showing Monsanto used ghostwriters and waged campaigns to influence editorial decisions at academic journals, with the apparent goal of “manipulat[ing] the regulatory process so that it could continue selling a product that the firm’s own research indicated might be dangerous.”

In response to a request for comment, Bayer’s head of crop science communications and sustainability, Jessica Christiansen, wrote in an emailed statement, “We support a predictable and science-based regulatory system and the certainty and availability it provides to American farmers.”

Glenna explained that both the public and regulators tend to trust peer-reviewed studies, and distrust company-sponsored research. That’s why in one email, a Monsanto employee explicitly says the goal of keeping people from the company listed as authors is “to help enhance credibility.” Other emails show selective interpretations of toxicity results, and more concern over preventing follow-up studies than public safety.

The EPA drew on these kinds of studies when they concluded in 2016 that glyphosate was “not likely to be carcinogenic to humans,” and it issued a decision to reapprove the pesticide in 2020. That directly contradicts research from leading global authorities at the World Health Organization (WHO), who found glyphosate is a probable carcinogen in 2015. The EPA relied heavily on unpublished regulatory studies, while the international health organization relied primarily on peer-reviewed work.

In 2022, the Ninth Circuit Court of Appeals determined the EPA’s decision was based on faulty procedures, noting the agency’s own scientific advisory panel had criticized the criteria that the agency used. They required the EPA to reevaluate the pesticide; two years later, it still hasn’t done so.

“Freedom to Operate”

These kinds of pesticide registration reviews are routinely delayed. Part of the problem, Glenna says, is that regulators have to rely on industries to release toxicology information because it’s considered proprietary information. “[It’s] intellectual property,” he says, “so university or publicly funded scientists simply don’t have the ability to do the research.”

When a pesticide is first registered with federal regulators, the vast majority of the information available about it is science conducted by the company who made it. “The presumption in the US is in favor of the safety of the chemical,” Burd says. Elsewhere, like the European Union, “chemicals are not presumed safe, they adopt a much more precautionary approach.”

In fact, according to federal law, the EPA can only refuse to register a pesticide if its risks are greater than the benefits it provides, as measured by crop yield or quality. As a result, close to a third of US pesticide use involves chemicals banned in China, Brazil, and the European Union.

There’s also a revolving door between the agency and the industry it regulates. Alexandra Dunn, the former assistant administrator for the Office of Chemical Safety and Pollution Prevention, for example, is now running CropLife America, the pesticide industry’s leading lobbying group. She’s only the latest; since 1974, all of the office’s directors went on to work for pesticide companies.

This industry influence within the agency is exacerbated by the fact that about 40 percent of the funding for the EPA’s Office of Chemical Safety and Pollution Prevention comes from registration fees — paid by the companies themselves.

Monsanto described the way it took advantage of this regulatory environment as “Freedom to Operate,” an operating principle which it defined in internal company emails as “the set regulatory, technical, marketing, and communication actions to set up a more favorable environment to secure the authorizations of our products and technologies.”

These actions included awarding employees for defending the company after the WHO’s designation of Roundup as a carcinogen, and finessing sick employees’ workplace exposure reports.

Regulators may soon be taking a further step back. Project 2025, a report of conservative policies developed by corporate interests to shape a future Donald Trump administration, claims the EPA’s programs are “constantly pressured to ban the use of certain chemicals, typically based on fear as a result of mischaracterized or incomplete science.” It wants to ensure US chemical regulations remain “risk-based, rather than defaulting to precautionary, hazard-based approaches.”

Ultimately, it advocates that “[f]armers, and the food system should be free from any unnecessary government intervention” and that agricultural regulators should be prioritizing “personal freedom, private property and the rule of law.”

“An Existential Threat”

Although Bayer insists that the product it inherited from its 2018 merger with Monsanto is safe, it is facing over 170,000 glyphosate lawsuits, even after a $10 billion settlement in 2020 with thousands of victims who say the pesticide caused their illnesses. This spring, the biotech giant has been lobbying Congress to restrict the company’s liability for lawsuits over glyphosate exposure, including working to draft language on the matter in the upcoming farm bill.

According to the Washington Post, Reps. Dusty Johnson (R-SD) and Jim Costa (D-CA) worked closely with the company to draft the measure forestalling future payouts for glyphosate lawsuits, which was later added to the farm bill, which sets the country’s agriculture policy every five years and slated for a vote this fall. The company’s political action committee has also contributed to both Johnson and Costa’s campaigns for several election cycles.

At a speech during a conference this spring, Bayer’s CEO Bill Anderson called its potential legal liability for the health impacts of its pesticides an “existential threat.” It’s now considering whether to use a strategy called the Texas two-step. In this legal maneuver, a company splits in two, with one half keeping the assets and the other the liabilities. The latter then files for bankruptcy, forcing people seeking compensation into bankruptcy court, which often results in delayed or lower settlements.

In addition to its federal lobbying, Bayer has also doubled down on lobbying state by state. It supplied similar language for bills introduced in Missouri, Florida, Idaho, and Iowa this year that would shield pesticide companies from future glyphosate lawsuits, in part by excluding these companies from states’ requirements to inform about their potential dangers or risks.

In her statement to the Lever, Bayer’s Christiansen wrote the company’s “support of legislation like this at both the federal and state level helps protect the integrity of the regulatory process and helps ensure that the EPA’s thorough and scientifically based conclusions are the basis for crop protection labels.”

In Idaho, Bayer’s deputy of state and local government affairs personally presented the bill the company hoped to pass to a Senate committee. To marshal support for the bill, the company increased its expenditures in the state, spending more than $8,000 and employing at least three people. It ran ads in local newspapers proclaiming, “Side with Idaho Farmers Not Trial Lawyers.” Bayer also created a multistate coalition called Modern Ag Alliance, claiming eight hundred jobs in Idaho are connected to glyphosate production, along with five hundred in Iowa.

The legislative initiatives were defeated in Idaho and Florida, but passed the state Senate in Iowa, and is still working its way through Missouri’s house.

These tactics are all part of the company’s five-part plan to handle its liability, which it’s using to reassure anxious shareholders. According to company documents, the first step is to “seek positive ruling from the US Supreme Court.”

As in its proposed state bills, the company argues that since the EPA has so far concluded glyphosate doesn’t cause cancer, and does not require a warning label, state failure-to-warn laws should be preempted. They have filed two federal lawsuits toward this end, which are currently winding through the courts.

Burd says she’s not surprised by Bayer’s maneuvering, but “what’s disappointing is that there are so many legislators willing to go along with it.”

While glyphosate has a high profile, Rocky Vista University’s Zapata says the ultimate problem is far more complex than just one pesticide, or even a company as influential as Bayer.

“The fact that we don’t hear about other stuff doesn’t mean it’s not a problem,” he says. That’s why his recent study tried to capture the big picture of how collectively, these compounds are actually influencing people’s health.

He says his motivations are apolitical — and that there’s plenty of blame to go around. “If we want to go to the grocery store and have cheap tomatoes, they’re likely going to be produced using a very industrialized system,” he says.

Meanwhile, he’s aware that disclosing these kinds of risks has an economic and ethical value. “If you buy land in an area with high agricultural capacity, you’re also buying some of that risk,” he says. And the people who have the ability to choose to live elsewhere, or who are wealthy enough to not need to work low-wage jobs with increased exposure, are simply outsourcing that hazard.

“If you don’t live in that place, somebody else will have to,” Zapata says.