Act of resistance follows trade ruling that dismissed risks to native corn from “genetic pollution” by GM crops.
By Timothy Wise
On March 17, Mexican President Claudia Scheinbaum Pardo signed into law a constitutional reform banning the cultivation of genetically modified corn. The action followed a December ruling by a trade tribunal, under the U.S.-Mexico-Canada (USMCA) trade agreement, in favor of a U.S. complaint that Mexico’s 2023 presidential decree, with broader restrictions on the consumption of GM corn, constituted an unfair trade practice by prohibiting the use of GM corn in tortillas.
The Mexican government publicly disagreed with the ruling, claiming that the three arbitrators had failed to consider the scientific evidence Mexico presented in the yearlong case. But the government chose to comply, rescinding the three specific parts of the decree deemed by the panel to limit future GM corn imports. Still, the government left intact the decree’s measures phasing out the use of the herbicide glyphosate, establishing a protocol for tracking GM corn imports into the country, and banning the cultivation of GM corn in the country.
The constitutional amendment enshrines that last measure in a more permanent manner. While GM corn has faced planting restrictions for more than a decade, the constitutional ban represents an important act of resistance and sovereignty, particularly in light of the flawed decision by the tribunal.
Trade panel fails to consider evidence
Corn is central to Mexico’s agriculture, cuisine, nutrition, and culture. Mexico is the center of origin for corn, where the crop was domesticated thousands of years ago. It remains at the core of the country’s farming, diet, and culture. As President Sheinbaum acknowledged in approving the constitutional ban on GM corn cultivation, “Sin maiz no hay pais”—without corn there is no country.
Mexico presented strong evidence that GM corn has cross-pollinated native corn varieties, gene flow that threatens to undermine the genetic integrity of the country’s 64 “landraces” and more than 22,000 varieties adapted by farmers over millennia to different soils, altitudes, climates, foods, and customs.
In defense of Mexico’s 2023 decree, the panel acknowledged that the government presented scientific evidence from qualified and reputable sources of “risks to human health arising from the direct consumption of GM corn grain in Mexico, and risks to native corn of transgenic contamination arising from the unintentional, unauthorized, and uncontrolled spread of GM corn in Mexico.” (That evidence is summarized in an extensive publication from Mexico’s national science agency, CONAHCYT.)
The trade tribunal dismissed concerns about such risks in its ruling, in the process repeating several fallacies about the robust scientific evidence presented by the Mexican government. In effect, the tribunal gave itself a pass on reviewing the scientific evidence of risks to human health by ruling that Mexico had not conducted an approved risk assessment “based on relevant scientific principles,” a reference to prevailing international codes for such processes.
The panel also failed to evaluate the evidence of risks to native corn. The tribunal argued that no special protection from GM corn was needed because gene flow already takes place from non-GM hybrid varieties of corn, and GM contamination is no different from non-GM gene flow. “Mexico has not demonstrated how the threat to the traditions and livelihoods of indigenous and farming communities from GM corn is greater than the threat posed by non-native, non-GM corn,” the panel wrote.
This lazy logic flows easily from biotech industry talking points, and it makes no sense at all in the birthplace of corn. In effect, the tribunal claimed that cross-pollination from hybrid corn; “could equally threaten the genetic integrity of native corn.” The discredited notion of “substantial equivalence” between GM crops and their conventionally bred hybrid counterparts has been further undermined by new research techniques that show distinct gene expressions in the cells of GM plants. Those techniques were explained in some detail in expert testimony submitted by molecular geneticist Michael Antoniou, but the panel never got his testimony translated, nor those of three other experts. Not surprisingly, the ruling had no mention of Dr. Antoniou’s contribution.
Equating contamination from GM corn with that of hybrid corn is a serious misreading of the science and of Mexico’s culture. GM by definition—and by explicit definitions in the constitutional amendment—involves crossing species boundaries, introducing, for example, a gene from a bacterium into a corn plant to repel insects. In contrast, hybrid corn is produced by cross-breeding different corn varieties. The resulting hybridized offspring remains pure corn, with no non-corn genes in its DNA.
Mexico’s constitutional ban on GM corn cultivation ensures that such misguided reasoning will not guide public policy. The amendment was strengthened by proposals from civil society that extended the ban to new genetically engineered seeds by banning any crops “produced with techniques that overcome the natural barriers of reproduction or recombination, such as transgenics.” This limits some of the new generations of genetically engineered crops, putting Mexico ahead of Europe in its limits on such technologies.
While the constitutional reform does not include some of the original language restricting GM corn consumption, no doubt in deference to the trade ruling, the final version shows a clear preference for non-GM crops, leaving the door open to tighter regulation.
It is no wonder the Mexican government proceeded with its constitutional amendment to ban the cultivation of GM corn. This is “a major step forward for the defense of native corn varieties, the health of the Mexican population, and the protection of Mexico’s biocultural heritage associated with corn,” said Tania Monserrat Téllez from the Sin Maíz No Hay País coalition.
While Mexico chose to comply with the flawed USMCA ruling, there is little evidence that Mexicans will stop fighting to keep GM corn out of their tortillas. Recent polls showed that more than 80% of Mexicans want tortillas free of GM corn. A new mill is now open, dedicated to handling only non-GM corn, and the government is redoubling efforts to increase domestic production of non-GM corn for the sector. The original presidential decree still calls for the phaseout of glyphosate-based herbicides and mandates procedures for tracking GM corn coming into Mexico. A “Right to Food” law passed last year calls for labeling all foods that contain GM ingredients. That process could take time to implement, but don’t be surprised if consumer and tortilla industry groups act sooner to agree on a voluntary label for GM-free tortillas.
It’s time to give Mexicans what they want: GM-free fields and tortillas, and food sovereignty.
This is an edited version of an article that appeared on Medium.
To view the source article, visit: https://tawise01.medium.com/mexicos-enacts-constitutional-ban-on-cultivation-of-genetically-modified-corn-b7a8a2e820a6
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