By Renee Hickman
CHICAGO, July 13 (Reuters) - The U.S. Supreme Court handed a major legal victory to German agrichemical and pharmaceutical company Bayer last month when it reined in thousands of lawsuits accusing the German company of failing to warn users that glyphosate, the active ingredient in its Roundup weedkiller, causes cancer.
Since then, Bayer, which acquired U.S.-based Roundup maker Monsanto in 2018, has consolidated its Roundup business into a new unit, and sought duties on glyphosate
imported from China.
The pesticide industry has secured other successes in recent months. In February, weedkiller dicamba was re-approved for two growing seasons with some restrictions. In April, a U.S. Fish and Wildlife Service biological opinion concluded that atrazine does not pose an extinction risk to threatened and endangered species it studied.
In Bayer's case, President Donald Trump's administration sided with the Roundup maker, a position that caused a rift with pesticide opponents in U.S. Health and Human Services Secretary Robert F. Kennedy Jr.'s "Make America Healthy Again" movement, who supported Trump in the 2024 election campaign.
Ken Cook, CEO of the Environmental Working Group, a non-profit that advocates for restrictions on pesticides, said Trump's administration seems to have decided that "our constituency is these big farmers and pesticide companies."
His organization and others seeking limits on pesticide use have long been disappointed with the EPA's pesticide program. Under former President Joe Biden, "it was at least more cautious," Cook said. "There's a big shift."
But the EPA said its decisions, which in some cases include new restrictions on applications, mean that "the impact for farmers and the environment is straightforward. Growers get modern, more precise chemistries that do more with less."
Bayer said the Supreme Court decision was "good for science, farmers, and industries that depend on regulatory clarity for innovation."
Here is the current legal and regulatory status in the U.S. of three of the most hotly debated pesticides:
GLYPHOSATE SCORES WIN IN US SUPREME COURT
On June 25, the Supreme Court gave Bayer its biggest win yet. In a 7-2 decision, justices said plaintiffs cannot sue the company for breaking state laws by not including a label warning about cancer risk.
Bayer shares shot up to their biggest gains in 23 years in the wake of the decision. The company had faced tens of thousands of lawsuits from Roundup users who said the product caused their cancer.
On Thursday, Bayer sought to convince a federal judge to dismantle federal litigation that consolidates nearly 4,000 lawsuits alleging that Roundup causes cancer. Ending that litigation would lift a financial burden that Bayer has warned could cause it to stop producing the weedkiller.
Glyphosate has drawn fire for years from critics who say it causes cancer and other health problems. Bayer maintains the pesticide can be used safely.
DICAMBA APPROVED FOR TWO GROWING SEASONS
A weedkiller manufactured by Bayer and Syngenta, dicamba is sprayed by farmers on cotton and soybean crops that have been genetically engineered to tolerate it.
Environmental groups have criticized its use because it can drift away from where it is sprayed and damage neighboring plants.
In 2024, a U.S. District Court ruled that the U.S. Environmental Protection Agency had previously violated public input procedures in its approval of three dicamba products, and vacated the product registrations. As a result, farmers were unable to spray dicamba on crops in 2025.
In February 2026, the EPA announced it had approved products containing the pesticide for the next two growing seasons under new guidelines, including cutting the maximum application rate and limiting applications in hot weather.
In response, the non-profit Center for Biological Diversity, which opposes use of dicamba, said those measures would be ineffective and difficult to enforce.
In an email, EPA said the approval was "deliberately temporary" and included "the strictest guardrails EPA has ever placed on this herbicide."
US AGENCY SAYS ATRAZINE DOES NOT POSE EXTINCTION RISK
Atrazine, a widely used herbicide produced by Syngenta, is mostly used on farms for crops including sugarcane and corn.
Some scientific studies have shown a possible link between atrazine and higher rates of certain kinds of cancers, as well as pre-term births, according to the Centers for Disease Control and Prevention.
The EPA is currently conducting a registration review of the chemical and in May, as part of that review, the U.S. Fish and Wildlife Service presented a biological opinion that atrazine does not pose an extinction risk to the threatened or endangered wildlife it studied.
"We anticipate that the registration of atrazine is not likely to jeopardize the continued existence of these species," the agency wrote in its opinion.
The review is one step in the EPA's registration review process for the pesticide.
That conclusion was a shift from the EPA's 2021 biological evaluation, which found the chemical was likely to adversely affect over 1,000 protected species.
“Instead of taking the environmental and health risks of atrazine seriously, the Trump administration has once again done the pesticide industry’s bidding, allowing this extraordinarily dangerous pesticide to continue poisoning our land and water for decades to come,” Nathan Donley, environmental health science director for the Center for Biological Diversity, said in a statement.
The EPA emphasized that the opinion was made outside its agency, and that it would weigh any new science as its registration review continues.
In 2025, the World Health Organization’s International Agency for Research on Cancer found atrazine to be “probably carcinogenic to humans.”
On an atrazine website created by Syngenta, the company said that when used as directed, the chemical does not cause adverse effects to human health or the environment.
(Reporting by Renee Hickman; Editing by David Gregorio)
