Mexican farmer Arnulfo Melo show harvested corn from his organic corn field

Farmer Arnulfo Melo shows harvested corn from his organic field in Milpa Alta, Mexico, on October 18, 2021, months after the Mexican government banned genetically modified corn for human consumption.

(Photo: Rodrigo Arangua/AFP via Getty Images)

Experts Warn of Toxins in GM Corn Amid US-Mexico Trade Dispute

"The Mexican government is both wise and on solid ground in refusing to allow its people to participate in the experiment that the U.S. government is seeking to impose."

Friends of the Earth U.S. on Monday released a brief backing Mexico's ban on genetically modified corn for human consumption, which the green group recently submitted to a dispute settlement panel charged with considering the U.S. government's challenge to the policy.

Mexican President Andrés Manuel López Obrador announced plans to phase out the herbicide glyphosate as well as genetically modified (GM) or genetically engineered (GE) corn in 2020. Last year he issued an updated decree making clear the ban does not apply to corn imports for livestock feed and industrial use. Still, the Biden administration objected and, after fruitless formal negotiations, requested the panel under the United States-Mexico-Canada Agreement (USMCA).

"The U.S. government has not presented an 'appropriate' risk assessment to the tribunal as called for in the USMCA dispute because such an assessment has never been done in the U.S. or anywhere in the world," said agricultural economist Charles Benbrook, who wrote the brief with Kendra Klein, director of science at Friends of the Earth U.S.

"The U.S. is, in effect, asking Mexico to trust the completeness and accuracy of the initial GE corn safety assessments carried out 15 to 30 years ago by the companies working to bring GE corn events to market."

The group's 13-page brief lays out health concerns related to GM corn and glyphosate, and the shortcomings of U.S. analyses and policies. It also stresses the stakes of the panel's decision, highlighting that "corn is the caloric backbone of the Mexican food supply, accounting, on average, for 50% of the calories and protein in the Mexican diet."

Blasting the Biden administration's case statement to the panel as "seriously deficient," Klein said Monday that "it lacks basic information about the toxins expressed in contemporary GMO corn varieties and their levels. The U.S. submission also ignores dozens of studies linking the insecticidal toxins and glyphosate residues found in GMO corn to adverse impacts on public health."

The brief explains that "since the commercial introduction of GE corn in 1996 and event-specific approvals in the 1990s and 2000s, dramatic changes have occurred in corn production systems. There has been an approximate fourfold increase in the number of toxins and pesticides applied on the average hectare of contemporary GE industrial corn compared to the early 1990s. Unfortunately, this upward trend is bound to continue, and may accelerate."

The U.S. statement's assurances about risks from Bacillus thuringiensis or vegetative insecticidal protein (Bt/VIP) residues "are not based on data and science," the brief warns.

"The U.S. is, in effect, asking Mexico to trust the completeness and accuracy of the initial GE corn safety assessments carried out 15 to 30 years ago by the companies working to bring GE corn events to market," the document says. "The Mexican government is both wise and on solid ground in refusing to allow its people to participate in the experiment that the U.S. government is seeking to impose on Mexico."

"The absence of any systematic monitoring of human exposure levels to Bt/VIP toxins and herbicides from consumption of corn-based foods is regrettable," the brief adds. "It is also unfortunate that the U.S. government rejected the Mexican proposal to jointly design and carry out a modern battery of studies able to overcome gaps in knowledge regarding GE corn impacts."

"The U.S. government's case against Mexico has no more scientific merit than its sham GMO regulatory regime, and should be rejected by the USMCA dispute resolution panel."

Friends of the Earth isn't the only U.S.-based group formally supporting the Mexican government in the USMCA process. The Center for Food Safety sent a 10-page submission by science director Bill Freese, an expert on biotech regulation, to the panel on March 15. His analysis addresses U.S. regulation of genetically modified organisms (GMO) along with the risks of GM corn and glyphosate.

"GMO regulation in the U.S. was crafted by Monsanto, now owned by Bayer, and is a critical part of our government's promotion of the biotechnology industry," Freese said last week, referring to the company known for the glyphosate-based weedkiller Roundup. "The aim is to quell concerns and promote acceptance of GMOs, domestically and abroad, rather than critically evaluate potential toxicity or allergenicity."

His submission notes that the U.S. Food and Drug Administration "does not require a GE plant developer to do anything prior to marketing its GE crop or food derived from it. Instead, FDA operates what it calls a voluntary consultation program that is designed to enhance consumer confidence and speed GE crops to market."

"When governmental review is optional; and even when it's conducted, starts and ends with the regulated company's safety assurance—what's the point?" Freese asked. "Clearly, it's the PR value of a governmental rubber stamp."

"The Mexican government's prohibition of GM corn for tortillas and other masa corn products is fully justified," he asserted. "The U.S. government's case against Mexico has no more scientific merit than its sham GMO regulatory regime, and should be rejected by the USMCA dispute resolution panel."

In a Common Dreams opinion piece last week, Ernesto Hernández-López, a law professor at Chapman University in California, pointed out that Mexico's recent submission to the panel also "offers scientific proof and lots of it," including "over 150 scientific studies, referred to in peer-review journals, systemic research reviews, and more."

"Mexico incorporates perspectives from toxicology, pediatrics, plant biology, hematology, epidemiology, public health, and data mining, to name a few," he wrote. "This clearly and loudly responds to American persistence. The practical result: American leaders cannot claim there is no science supporting the decree. They may disagree with or dislike the findings, but there is proof."

The Biden administration's effort to quash the Mexican policy notably comes despite the lack of impact on trade. While implementing its ban last year, "Mexico also made its largest corn purchase from the U.S., 15.3 million metric tons," National Geographicreported last month.

Kenneth Smith Ramos, former Mexican chief negotiator for the USMCA, told the outlet that "right now, it may not have a big economic impact because what Mexico is using to produce flour, cornmeal, and tortillas is a very small percentage of their overall imports; but that does not mean the U.S. is not concerned with this being the tip of the iceberg."

Join Us: News for people demanding a better world


Common Dreams is powered by optimists who believe in the power of informed and engaged citizens to ignite and enact change to make the world a better place.

We're hundreds of thousands strong, but every single supporter makes the difference.

Your contribution supports this bold media model—free, independent, and dedicated to reporting the facts every day. Stand with us in the fight for economic equality, social justice, human rights, and a more sustainable future. As a people-powered nonprofit news outlet, we cover the issues the corporate media never will. Join with us today!

Our work is licensed under Creative Commons (CC BY-NC-ND 3.0). Feel free to republish and share widely.