Mapping the Human Chemical Exposome Across Biological Matrices

Understanding how environmental chemicals distribute and persist across human tissues is essential to interpret exposure and biological response. This question becomes especially critical in certain situations, such as during fetal development, when multiple biological barriers regulate the exchange of chemicals between the mother and the developing child. Yet, characterizing this complex chemical landscape remains analytically challenging due to the diversity of matrices, concentrations, and compound classes involved.
In this talk, I will discuss how advanced LC–high-resolution mass spectrometry (LC-HRMS) can be applied to map chemical distribution across interconnected biological compartments, including urine, serum, placenta, and cord blood, providing an integrated view of internal exposure. HRMS workflows enable the detection of hundreds of environmental chemicals and transformation products spanning a broad polarity and volatility range. Combining targeted and untargeted analyses allows us to resolve tissue-specific partitioning patterns and identify physicochemical and biological determinants of transport across interfaces such as the placenta.
In this context, I will also address one important analytical bottleneck in multi-matrix exposomics: the high intraindividual variability observed in chemical concentrations. Such variability can arise from short-term exposure fluctuations, sampling conditions, and analytical uncertainty, complicating the interpretation of exposure levels and highlighting the need for strategies to obtain more reliable and adjusted estimates. These approaches are essential to draw meaningful conclusions and enhance biological interpretability.
Together, these efforts illustrate how multi-matrix exposomics provides a scalable analytical framework to understand chemical transport within the human body, ultimately linking exposure to molecular and health outcomes.