Glyphosate and AMPA in saliva and other traditional human matrices. New findings for less invasive biomonitoring to the exposure to pesticides

Abstract

Human biomonitoring of the exposure to pesticides is usually performed in biological matrices such as urine and plasma. However, the possibility of using less invasive matrices allows the screening of large number of subjects. The objective of this study was to evaluate the body burden of the exposure to the most widely used herbicide, Glyphosate (GLY), and its main metabolite, the aminomethylphosphonic acid (AMPA), in different populations from the province of Córdoba (Argentina), and to propose the saliva as a matrix for possible implementation in biomonitoring of the exposure to pesticides. Glyphosate and AMPA concentrations were evaluated in urine, plasma, and saliva of subjects occupationally and environmentally exposed to pesticides from one of the most important agricultural areas of Argentina. Gas chromatography coupled to tandem mass spectrometry (MS/MS) was used for the identification and quantification of the analytes. Both GLY and AMPA were quantified in all matrices with higher detection frequency (DF) in the occupationally exposed group than in non-occupationally exposed individuals. Among evaluated matrices, the highest DF and concentration levels of GLY were found in saliva. Moreover, the only statistical difference between groups of subjects were found for GLY and AMPA concentrations in saliva, indicating the possible use of this non-invasive human matrix to evaluate different levels and scenarios of exposure. No significant correlation was found between GLY and AMPA levels in saliva and the traditional matrices (urine and blood) used to measure exposure to pesticides. This is the first report of the presence and concentrations of GLY and AMPA in human saliva samples. Results of the present study are relevant for future biomonitoring of the exposure to GLY, but also to pesticides in general. Saliva deserved further investigation as an alternative, easy, and economical matrix involving less invasive methods for biomonitoring and screenings of large populations.