# Simultaneous Determination of Glyphosate, Aminomethylphosphonic Acid, and Glufosinate in Green Coffee Beans by LC-MS/MS: Optimization, Validation, and Field Study

## TL;DR

This study developed a reliable and cost-effective method to detect glyphosate and related herbicides in green coffee beans, enabling better compliance with international regulations.

## Contribution

A validated LC-MS/MS method for glyphosate, AMPA, and glufosinate in green coffee beans without derivatization.

## Key findings

- The method achieved quantification limits of 0.02 mg kg–1 for glyphosate, 0.04 mg kg–1 for AMPA, and 0.01 mg kg–1 for glufosinate.
- Plant height was identified as the primary factor influencing herbicide residue levels in coffee crops.
- The method was validated according to SANTE/11312/2021 guidelines, showing good linearity, precision, and accuracy.

## Abstract

Despite the widespread use of glyphosate in coffee crops,
there
is a lack of simple, low-cost, validated methods for detecting glyphosate
and related compounds in green coffee beans, the primary export form
subject to international regulation. This study optimized and validated
a liquid chromatography with tandem mass spectrometry method for the
determination of glyphosate, aminomethylphosphonic acid (AMPA), and
glufosinate in green coffee, using a modified QuPPe-PO extraction
followed by a cleanup combining liquid–liquid extraction and
dispersive solid-phase extraction. Validation followed SANTE/11312/2021
guidelines, confirming the method’s linearity, precision, accuracy,
and quantification limits. Limits of quantification were 0.02 mg kg–1 (glyphosate), 0.04 mg kg–1 (AMPA),
and 0.01 mg kg–1 (glufosinate). The method was applied
to a field study with Arabica coffee and Conilon Coffee, revealing
that plant height was the primary factor influencing residue levels.
The proposed method enables reliable monitoring of polar herbicides
in coffee without the need for derivatization.