BUENOS AIRES — Since the International Agency for Research on Cancer recently cited the pesticide glyphosate as a possible cancer agent, the issue has been logically extended from its use on illicit coca plantations to foods that families consume every day.

I have closely followed scientific debates about the indiscriminate use of chemicals in farming and their possible ties to cancer, and frankly I feel uneasy these days when I bite into a juicy corncob.

In Argentina, where glyphosate is used copiously in farming corn, soy and other products, the debate has been intense and worrying. Every year, Argentina exports thousands of tons of various foodstuffs to other countries, including Colombia.

Our trade promotion agency ProColombia estimates the volume of our food imports from Argentina last year at over 894,000 tons, worth more than $201 million. The problem is that environmentalists in Argentina and abroad are strongly questioning food production methods there, and the list of Argentine foods we eat is long: soybeans, soy oil, soy flour, corn, sunflower seeds, sunflower oil, wheat, peanuts, sorghum, onions and pears, among many others.

Colombia recently decided to stop the aerial spraying of glyphosate on illegal coca plantations, but many wonder now about other foods sprayed with chemical pesticides. It's not an easy debate, and arguments abound on both sides.

A police plane sprays herbicides over a Colombian coca field — Photo: U.S Government

One of those who most recently questioned the safety of the glyphosate that Argentine farming companies spray on their products is scientist Andrés Carrasco, head of Argentina's CONICET research council and of the Molecular Embryology Lab at Buenos Aires University. He submitted a study in 2009 that showed the product's toxic effects on amphibian embryos.

Even Argentina's national food safety authority has warned various districts about pesticide residue (such as glyphosate and Endolsufan, the latter banned in the EU as harmful) on vegetables, as journalist Patricio Eleisegui revealed in his book Envenenados.

Moving through the Argentine countryside, it takes no more than a glance to see how its modern production system works. There are no farm laborers working the land, just operators inside monster machines that do everything. They plow the land, sow the seeds and spray pesticide to protect crops from plagues.

The soy business has been so profitable that it generated $23 billion in revenues last year, according to the website Infobae Argentina. But in the shadow of this success are the victims of massive pesticide use: the spraying operators, farm hands, rural residents and even the producers, says Fabián Tomasi, a sprayer who has become chronically ill.

Food that makes you sick

The UN cancer agency's recent alert seemed to affirm what activists have been saying for years about pesticide damage to their health, and the research of scientists who have sought to demonstrate the side effects of Roundup, the world's favorite pesticide produced by Monsanto.

Eleisegui's book cites many studies on glyphosate in Argentina. The author cites biologist Raúl Montenegro, who has shown that fruit and vegetables sprayed with pesticides carry residues "because of the appalling control systems applied."

Likewise, blood tests carried out around Mar de Plata by BIOS, a green NGO, in collaboration with university scientists, showed that not only is there glyphosate inside people's bodies but that the residue accumulates over time. Another study by Littoral University and CONICET showed residue of endosulfan and glyphosate in green soy grains.

With corn, a study by Frenchman Gilles Eric Séralini (published last year in Environment Sciences Europe) demonstrated the harmful effects of food contaminated by glyphosate. (Monsanto declined comment on these studies.)

Colombia is the second-largest regional buyer of Argentine soybeans (139,000 tons in 2013-14), and the top regional buyer of Monsanto's genetically modified corn (NK603).

The bottom line is that the corn and soybeans we buy in our supermarkets very likely contain pesticide residues, and their long-term consumption could cause cancer.