Pervasive presence of transgenes and glyphosate in maize-derived food in Mexico

<p>In Mexico, the Center of origin and diversity of maize, a daily per capita average of 0.5 kg of maize-based foods are consumed. Approximately 10 million tons of maize is produced in small peasant holdings. Nevertheless, a greater proportion of industrially produced maize-derived products have started to appear in recent years. We traced the presence of transgenes and glyphosate in maize-based foods collected in Mexico and elsewhere as a means to describe the landscape of distribution, abundance, and types of transgenes in maize-derived food in Mexico. Transgenic sequences were present in overall 82% of assayed food categories; while the most widely form of maize consumption in Mexico, tortillas, had recombinant sequences in 90.4% of the samples. Furthermore, we found statistically indistinguishable frequency distributions of transgenes in samples from Mexico and other countries. Additionally, glyphosate was detected in approximately 27.7% of the samples rendered positive for transgenic events tolerant to this herbicide.</p