Determination of Glyphosate and Aminomethylphosphonic Acid (AMPA) in Grains in Brazil: Integration of Bioaccessibility Studies with Risk Assessment for Human Health

• Grant number: 25/00611-7
• Support Opportunities: Scholarships in Brazil - Master
• Start date: April 01, 2025
• End date: November 30, 2026
• Field of knowledge: Health Sciences - Pharmacy - Toxicological Analysis
• Principal Investigator: Marília Cristina Oliveira Souza
• Grantee: Gabriel Henrique Savietto
• Host Institution: Faculdade de Ciências Farmacêuticas de Ribeirão Preto (FCFRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Associated research grant: 22/06443-0 - Bioavailability and bioaccessibility of pesticides and legacy pollutants in food: a public health risk assessment and creation of a risk-benefit tool for Brazilian consumers, AP.GR

Abstract

In Brazil, agriculture is one of the main economic pillars, experiencing exponential growth in recent years. The use of pesticides is a key factor in the viability of this large-scale agricultural productivity; however, it positions the country as one of the largest consumers of pesticides in the world. Glyphosate [N-(phosphonomethyl) glycine] is a herbicide that leads sales in Brazil and is the most widely used worldwide. Its high efficiency and low cost explain its widespread acceptance and intensive global use. Glyphosate is predominantly degraded and metabolized into aminomethylphosphonic acid (AMPA). Despite its low stability, glyphosate has attracted significant public and scientific interest due to its frequent detection in food, including those that form the dietary base of many populations, making it crucial to ensure food safety.In 2015, the International Agency for Research on Cancer (IARC) classified glyphosate as "possibly carcinogenic to humans," reinforcing the need for monitoring and assessment studies. Globally, the development of toxicological reference values for pesticide residues in food is an ongoing area of scientific research. However, in Brazil, such data remain scarce. Moreover, most data on human exposure to pesticides through oral ingestion disregard absorption processes in the gastrointestinal tract, which can overestimate health risks. In this context, determining bioaccessibility provides a more accurate estimate of these risks by measuring the fraction of the substance released during digestion. Given the limited availability of data on glyphosate residue concentrations in foods marketed in different regions of Brazil, this study aims to evaluate the levels of this herbicide and its main degradation product, AMPA, in grains-crops that are widely treated with glyphosate. Additionally, the study seeks to estimate the bioaccessible percentage of the herbicide. These results will enable a more precise risk assessment associated with dietary exposure to glyphosate and its derivatives.