The decision to allow genetically engineered corn to be sown inside Mexico, the birthplace of this cereal crop, is anathema for many Mexicans. In the central highlands, where wild grass called teosinte was first cross-bred into the staff of life some 9,000 years ago, corn is viewed not only as a staple food but as a sacrament of Mesoamerican civilization. Some indigenous tribes in Mexico still worship Centeotl, the Aztec corn god who protects harvests, and passions run high if any threat to corn is perceived.
Yet laboratory-altered corn, patented by the seed giants Monsanto and Dow AgroSciences, is already ripening on 13 hectares in Sinaloa and Sonora states, and the first harvest is expected later this month. An analysis is due in July. Farm groups and environmentalists filed an appeal with the Inter-American Commission on Human Rights in February, arguing that Mexican officials have been unwilling or unable to prevent the illegal spread of genetically modified crops in their country and that it is too soon to permit biotech plantations before the consequences of genetic contamination - possibly irreversible - are fully understood. They are concerned that Mexican seed dealers have smuggled in thousands of sacks of genetically modified corn with impunity. The commission can refer cases to the Inter-American Human Rights Court if a government does not comply with its recommendations.
"Small producers will be affected the most [by GM contamination], since they use native corn seed; the bigger producers all use sterile hybrids anyway," says Kirsten Appendini, an agrarian economist from the Colegio de Mexico. "The dependency of farmers on one big company for buying seeds is undesirable."
"The worry is that everybody will be affected by genetically modified corn, environmentally, through the reduction of biodiversity," Appendini adds. "As for the health issues - we don't know the consequences over time. So if you eat tortillas, as we all do, there are unknown risks." The concern is that, by manipulating genes in a plant that is consumed, biotechnicians might eventually trigger allergies, toxins, adverse nutritional effects or new diseases.
Typically, a Mexican eats nearly 10 times as much corn each year as an American, so when French researchers at Caen University concluded that rats had suffered kidney and liver damage after being fed genetically modified corn, Mexicans paid attention. Greenpeace Mexico launched a new campaign, "Hands off our corn!", and rallied in front of the local Monsanto office in April this year. Local celebrities joined activists to complain that allowing fields of genetically modified corn in the country violates "the human, economic, social and cultural rights of farm communities and consumers".
They also demanded that the government enforce mandatory labeling on genetically modified foods so that consumers can make an informed choice to avoid them. Considering that genetically modified corn products are ubiquitous in a multitude of local and imported processed foods containing glucose, maltodextrin, cornstarch, corn gluten, corn syrup, corn oil and the like, the task could be a logistical nightmare.
The new technology can seem rather ominous. "Pharma-crops first caused the widespread alarm inside Mexico," explains George Dyer, an expert on corn affiliated with the University of California. "It's possible to grow different molecules, say vaccines or antibodies, within the corn. Some are intended to be eaten. Other times the medical product is removed from the grain and marketed. But in places where people keep seed stocks, this is problematical. Using staple crops like corn to grow swine medicine that is not intended for human consumption was perceived as a risk."
Many Mexicans were shocked when Epicyte, a Californian biotech firm that is now defunct, designed an experimental contraceptive corn in 2001. A technique that transformed corn plants into horticultural mini-factories that could grow contraceptives in the field was misunderstood and rumoured to be an out-of-the-box solution to world hunger - a way to lower the sperm count of the peasants by doctoring their diet.
Controversy has raged in Mexico ever since contamination from transgenic corn was detected 1,400 kilometres south of the US border in an Oaxaca field by agronomists at the University of California, Berkeley in 2001. And genetically modified corn StarLink, approved solely for animal feed, had mysteriously ended up in supermarket taco shells manufactured in Mexico the year before. The rhetoric on both sides has been heated; mutual mistrust and acrimony have mounted over the years.
Opponents of genetically modified corn are derided as hysterical "globofobicos" (literally: fearful of globalization) - resistant to scientific advancement and ideologically opposed to multinational corporations. On the other hand, Monsanto is vilified as a profiteering poison-vendor, responsible for inventing the military defoliant Agent Orange and polychlorinated biphenyls (PCBs), but now trying to rebrand itself as a benign agri-business innovator, with a mission to end world hunger through improved crop yields.
Helen Rimmer, food campaigner at Friends of the Earth, takes issue with this self-image: "GM crops don't feed the world - they simply make record profits for the big businesses that sell the patented seeds and chemicals needed to grow them."
Even Nina Fedoroff, a tireless supporter of genetically modified foods and the science and technology adviser to US secretary of state Hillary Clinton, recently admitted: "We preach to the world about science-based regulations but really our regulations on crop biotechnology are not yet science-based."
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