What Happened to Glyphosate?
Glyphosate, the active ingredient in the widely used herbicide Roundup, has been at the center of a global controversy for decades, balancing its agricultural utility with increasing concerns over its potential health and environmental impacts. Despite regulatory bodies like the U.S. EPA maintaining its safety when used as directed, the World Health Organization's IARC classified it as 'probably carcinogenic to humans' in 2015, leading to thousands of lawsuits and billions in settlements by its manufacturer, Bayer (formerly Monsanto). As of April 2026, legal battles continue, with the U.S. Supreme Court hearing arguments on federal preemption of state-based warning claims, while the U.S. government has issued an executive order to boost domestic production, further intensifying the debate.
Quick Answer
Glyphosate, the active ingredient in Roundup, continues to be a highly contentious chemical, widely used in agriculture but facing ongoing legal challenges and scientific scrutiny regarding its links to cancer and other health issues. As of April 2026, Bayer, the manufacturer, is appealing to the U.S. Supreme Court to block state-based failure-to-warn lawsuits, arguing federal preemption. Concurrently, the U.S. government, through a February 2026 executive order, has designated glyphosate production as a national security priority, aiming to increase domestic supply amidst calls from scientists for tighter regulation due to strong evidence of health harms.
📊Key Facts
📅Complete Timeline14 events
Glyphosate First Synthesized
Swiss chemist Henry Martin, working for Cilag, first synthesized glyphosate, though the work was not published at the time.
Monsanto Discovers Herbicidal Activity
Monsanto chemist John E. Franz independently discovered glyphosate's herbicidal properties.
Roundup Introduced to Market
Monsanto commercially launched glyphosate under the brand name 'Roundup' for agricultural and residential use.
Roundup Ready GMO Crops Introduced
Monsanto introduced genetically modified 'Roundup Ready' crops (soy, corn, cotton) tolerant to glyphosate, leading to a massive increase in its use.
Monsanto's Glyphosate Patent Expires
Monsanto's key patent on glyphosate expired, opening the market to generic versions of the herbicide.
IARC Classifies Glyphosate as 'Probably Carcinogenic'
The International Agency for Research on Cancer (IARC), a branch of the WHO, classified glyphosate as 'probably carcinogenic to humans' (Group 2A).
Bayer Acquires Monsanto
German pharmaceutical and life sciences company Bayer acquired Monsanto for approximately $63 billion, inheriting the growing legal challenges related to glyphosate.
Bayer Settles Thousands of Lawsuits
Bayer announced settlements totaling over $11 billion to resolve more than 100,000 existing and future Roundup cancer claims.
9th Circuit Court Vacates EPA's Cancer Analysis
The U.S. Court of Appeals for the Ninth Circuit vacated the human health portion of the EPA's interim decision on glyphosate, finding its cancer analysis flawed and inconsistent with agency guidelines, ordering a reevaluation.
EU Renews Glyphosate Approval for 10 Years
The European Commission officially renewed the approval for glyphosate's use in the EU until December 15, 2033, following assessments by EFSA and ECHA.
Key Glyphosate Safety Study Retracted
A scientific journal retracted a 2000 paper that had asserted the safety of glyphosate, a study frequently cited in regulatory approvals.
Trump Executive Order Boosts Glyphosate Production
President Donald Trump issued an executive order to ramp up domestic production of glyphosate, designating it as critical to national food supply and security under the Defense Production Act.
Scientists Call for Urgent Glyphosate Regulation
The Seattle Glyphosate Symposium, attended by international scientists, concluded that evidence of glyphosate's harm to human health is strong and called for urgent regulatory action.
U.S. Supreme Court Hears *Monsanto v. Durnell*
The U.S. Supreme Court heard oral arguments in *Monsanto v. Durnell*, a case concerning whether federal law preempts state-based failure-to-warn claims regarding Roundup's alleged cancer risks.
🔍Deep Dive Analysis
Glyphosate (N-(phosphonomethyl)glycine) was first synthesized in 1950 by a Swiss chemist, but its herbicidal properties were discovered by Monsanto in 1970 and patented in 1971. Monsanto introduced it commercially as 'Roundup' in 1974, and its use dramatically expanded after the introduction of 'Roundup Ready' genetically modified crops in 1996, which were engineered to tolerate the herbicide, allowing farmers to spray fields without harming their crops. This led to a nearly 15-fold increase in glyphosate use globally.
The controversy surrounding glyphosate intensified significantly in March 2015 when the World Health Organization's International Agency for Research on Cancer (IARC) classified it as 'probably carcinogenic to humans,' citing 'limited evidence' in humans and 'sufficient evidence' in experimental animals for carcinogenicity, along with 'strong evidence' of genotoxicity. This classification sharply contrasted with the U.S. Environmental Protection Agency (EPA), which has repeatedly concluded that glyphosate is 'not likely to be carcinogenic to humans' when used according to label directions.
Following the IARC classification, thousands of lawsuits were filed against Monsanto (acquired by Bayer in 2018), alleging that Roundup caused non-Hodgkin lymphoma and that the company failed to warn consumers. Bayer has since spent over $11 billion settling more than 100,000 cancer lawsuits. Despite these settlements, Bayer continues to dispute the cancer link and is actively pursuing legal strategies to limit future liability. In June 2022, the U.S. Court of Appeals for the Ninth Circuit vacated the human health portion of EPA's interim decision on glyphosate, finding its cancer analysis flawed and inconsistent with its own guidelines, ordering a reevaluation.
As of 2026, glyphosate remains a central issue in agricultural policy, public health, and legal systems. In February 2026, President Donald Trump issued an executive order to ramp up domestic production of glyphosate, declaring it essential for national food supply and security, a move that drew criticism from health advocates. In March 2026, a 'Glyphosate Symposium' in Seattle, involving international scientists, concluded that evidence linking glyphosate to cancer and other health problems is now so strong that urgent regulatory action is needed. Most recently, in April 2026, the U.S. Supreme Court heard oral arguments in Monsanto v. Durnell, a pivotal case that could determine whether federal law preempts state-based failure-to-warn claims, potentially shielding companies like Bayer from future lawsuits. Simultaneously, the European Union renewed its approval for glyphosate use until December 2033, albeit with certain conditions and restrictions.
What If...?
Explore alternate histories. What if Glyphosate made different choices?