Session: Parallel session 1 - environmental analysis

High resolution mass spectrometry as a tool to improve the characterization of water environmentally relevant micropollutants

In the context of global environmental change and, more specifically, the anthropization of ecosystems, chemical contamination continues to represent a major challenge in terms of knowledge (Persson et al., 2022); a better understanding of it will ultimately enable it to be regulated, controlled and reduced. The situation in the aquatic environment is particularly alarming, given its role as the ultimate receptacle for pollutants, the vulnerability of organisms and its importance in both local and global cycles. Indeed, the introduction of toxic substances of synthetic or natural origin is an alarming factor in the deterioration of environmental quality. Knowledge of chemical contamination of aquatic environments has increased considerably in recent years (e.g., Wilkinson et al., 2022). However, many gaps remain. What's more, when we superimpose expected climate changes (altered temperatures, changes in precipitation patterns, etc.), it seems more than necessary to understand and anticipate their impact on water quality in terms of micropollutants. Climate change will also have an impact on our global lifestyles, leading to changes in the way we use chemicals (e.g., biocides and pesticides for both environmental and human health, and fluorinated compounds).

 

One of the essential foundations of better knowledge and therefore better management of chemical risk is a better understanding of the nature and presence of contaminants. This means developing metrological means of identification and characterization. Studies involve the molecular analysis of specific compounds present in trace or ultra-trace amounts (ppb or ppt) in highly complex matrices. Molecular speciation is a complex field in which, in addition to sample preparation, it is necessary to develop the most innovative molecular analysis techniques, combining chromatographic separation techniques with quantification and characterization techniques, often based on mass spectrometry. Transformation products (TPs) are one of a number of issues of major interest, as they may prove to be more persistent and/or more toxic than the parent molecule, for example through the acquisition of new physico-chemical properties that may render them genotoxic or mutagenic. The development of high-resolution mass spectrometry offers a tool for better characterization of the environmental chemical exposome. In this respect, chemical profiling approaches using high-resolution mass spectrometry (GC- and LC-HRMS) have opened up new opportunities for understanding the chemical exposome, the complex relationship between exposure and the biological effects observed, and more recently also for identifying transformation products (TPs). One of the major challenges of this approach still lies in processing the thousands of data sets generated, despite the constant evolution of treatment and chemoinformatics software and tools, both manufacturers and open source.