Trader Joe’s performs random audits of items with suspect ingredients, using an outside, third-party lab to perform the testing, the company said. Trader Joe’s system is not unlike that of the USDA, which requires sworn statements from food producers to certify organic foods. The agency requires test samples from approximately 5 percent of products, all of which must be GMO-free in order to be certified organic. For the other 95 percent, the agency relies solely on sworn statements.

Clif Bar & Co. also requires affidavits from ingredient suppliers demonstrating they can meet the company’s stringent non-GMO requirements.

Monsanto would have you believe that verifying and labeling for non-GMO ingredients is a costly and burdensome affair, but the fact that Trader Joe’s, known for its discount prices, can provide GMO-free private label products, which reportedly account for over two-thirds of the company’s estimated annual $9 billion in sales, takes the wind out of the “burdensome” argument. That leaves the cost of adding another line of ink to a label. Trader Joe’s doesn’t yet label its private label products as GMO- free, but the company cites a lack of clear labeling guidelines from U.S. governmental agencies as the reason it doesn’t label, not cost.

Megan Westgate, Executive Director of the Non-GMO Project confirmed what retailers who use the affidavit system said: “An affidavit system like what’s proposed in I-522 is a powerful way to have a significant impact on the food supply with minimal cost.”

As huge American Biotech companies Monsanto, DuPont, and ConAgra await imminent approval of their requests for permits to plant more than six million acres (an area larger than the size of El Salvador) in Mexico with GMO corn, resistance by peasant and indigenous organizations and their allies is mounting. If approved, this will be the first time commercial planting of GMOs has been allowed in the center of biodiversity of any crop. Although the stakes at this moment could not be higher, this is not a new battle. When Cortez conquered Mexico in the 1500s, the Spaniards began an offensive against what they viewed as lowly corn, trying to force indigenous farmers to grow wheat instead. Their efforts failed, as have countless attempts throughout Mexico’s history to eradicate a “corn culture” in which corn is more than a livelihood, more than a food, but also an identity, a basis of religion, and a part of the family.

At stake today are indigenous and campesino (peasant) cultural rights; Mexico’s food sovereignty; Mexico’s enormous biodiversity of corn adapted for countless climates, soils, and conditions; and the nation’s health (one of the types of corn they wish to grow, MON603, caused tumors-and other maladies-in rats in a recent peer-reviewed study by French scientist Gilles-Eric Séralini published in the journal Food and Chemical Toxicology).