Development and application of a LC-HRMS method for the identification and quantification of CECs concern in urine

Chemicals are everywhere in our daily lives, and we encounter them through various pathways. Human biomonitoring (HBM) is commonly used to understand our exposure to these chemicals. Traditionally, HBM focused on a limited number of chemicals analyzed with specific instruments. However, recent advancements in high-resolution mass spectrometry (HRMS) have allowed for a more comprehensive analysis of the chemical exposome. This study aimed to validate a methodology using HRMS to accurately profile exogenous chemicals and their metabolites in urine samples. Five extraction protocols covering different chemical classes were evaluated for their effectiveness in terms of extraction recoveries, linearity, sensitivity, and reproducibility. The best protocol was then validated (e.g., recoveries generally in between 60-120%, or lower matrix effect) and applied to analyze over 2,000 chemicals in 10 real human urine samples. Using the HRMS approach, 36 chemicals (e.g., plastic additives, UV-filters or pharmaceuticals) were identified and semi-quantified, demonstrating the effectiveness of the methodology. Interestingly, the laborious deconjugation step was deemed unnecessary as HRMS yielded comparable results without it, while also successfully identifying other metabolites.