Polar organic pollutants, micro-nano plastics and nanomaterials: Analytical techniques to reveal the still invisible human physico-chemical exposome

Large international biomonitoring initiatives have emerged to start mapping the exposure of humans to environmental contaminants. However, data are only available for a very limited number of contaminants, which reflects the lack of methods available for some chemicals (e.g., polar and ionic organic contaminants), or the lack of standardized methods for particulate contaminants such as micro-nano plastics and engineered nanomaterials. Here, we explore the advantages of analytical techniques that could improve the coverage of the human physico-chemical exposome. We first focus on the advantages of alternative methods, i.e., ion chromatography and capillary electrophoresis coupled to mass spectrometry, to improve the detection of polar and ionic substances. We then reviewed methods that have been used so far for the particulate characterization of human exposure, and discuss their applicability in large-scale programs. The complementary nature of the skill sets from exposure communities have the potential to close some current gaps in knowledge.