Biomonitoring of glyphosate and AMPA in the urine of Spanish lactating mothers

Abstract

The objectives of this study were to evaluate the urinary levels of Glyphosate (Gly) and its metabolite aminomethylphosphonic acid (AMPA) in Spanish breastfeeding mothers (n = 97), to identify the main predictors of exposure and to perform a risk assessment. Urine samples were analyzed using a method based on solid phase extraction and liquid chromatography tandem mass spectrometry (LC-MS/MS) determination. The developed method showed limits of quantification of 0.1 μg/L for both analytes. The detection frequencies (DFs) were 54% for Gly and 60% for AMPA, with geometric means (GMs) of 0.12 μg/L and 0.14 μg/L, respectively. In the statistical analysis, no relationship was found between the urinary levels of Gly and AMPA. Multiple regression analysis showed a significant relationship between the intake of eggs and fruits and Gly levels in urine. Estimated daily intakes (EDIs), hazard quotients (HQs), and a hazard index (HI) were calculated to analyze the obtained data from a health risk perspective. The GMs of the EDIs were 0.31 and 0.37 μg/kg of body weight (BW)/day for Gly and AMPA, respectively. The HQs were calculated considering 0.5 mg/kg BW/day as an acceptable daily intake (ADI), which EFSA has established as a health-based reference value for both analytes. The values obtained were lower than 1, and thus, low health risk due to Gly and AMPA exposure was expected for the population under study.

Keywords: AMPA; Glyphosate; Health risk; Lactating mothers; Urine.