A robust dilute-and-inject ion chromatography - Tandem mass spectrometry for urinary glyphosate quantification

Glyphosate is one of the most widely used herbicides in the world, whose potential effects on human health are still the subject of debate today. To assess the associated risks, reliable biomonitoring data are required using validated robust and sensitive analytical methods. In this context, an ion chromatography coupled with tandem mass spectrometry (IC-MS/MS) method was developed to quantify glyphosate in human urine. The method is based on direct injection of diluted urine samples. A labeled internal standard (¹³C₂ ¹⁵N₁ glyphosate) is added prior to injection to correct for losses or matrix effects during the analysis. The method limit of quantification (LOQ) is 0.1 ng/mL in urine. The working range was validated between 0.1 and 20 ng/mL. Method trueness was assessed at three concentration levels (LOQ, 2 and 20 ng/mL), and a full validation of the method was performed to characterize the analytical performance in terms of precision and measurement uncertainty.•Direct injection ion chromatography coupled with tandem mass spectrometry•Validation of the method according to international standards.