Residues of glyphosate and aminomethylphosphonic acid (Ampa) in genetically modified glyphosate tolerant soybean, corn and cotton crops

Abstract

Glyphosate is a broad-spectrum herbicide capable of controlling a wide range of weed. It uses could cause the occurrence of residues in conventional or genetically modified crops. For this purpose, grains (soybean and corn) and cotton seeds were sampled from commercial areas in 2012/2013 to 2017/2018 seasons in different Brazilian agricultural regions to monitor glyphosate residues levels and its metabolite (aminomethylphosphonic acid-AMPA) after different managements. The glyphosate residues levels ​in genetically modified corn (GM) ranged from no detected (ND) to 0.15 mg kg-1, in GM soybean values ​ranged from ND to 2.81 mg kg-1 and in GM cotton ranged from ND to 1.78 mg kg-1. AMPA residues levels ​indicated a correlation with the glyphosate residues. Glyphosate residues levels in soybean and corn grains and cotton seeds were within the Maximum Residue Limits (MRLs) established by ANVISA and Codex Alimentarius.