A Framework for Utilizing High-Resolution Mass Spectrometry and Non-targeted Analysis in Rapid Response and Emergency Situations

Unknown chemical releases constitute a large portion of the rapid response situations to which the US Environmental Protection Agency is called on to respond. Workflows used to address unknown chemical releases currently involve screening for a large array of known compounds using many different targeted methods. When matches are not found, expert analytical chemistry knowledge is used to propose possible candidates from the available data, which generally includes low-resolution mass spectra and situational clues such as the location of the release, nearby industrial operations, and other field-reported facts. The past decade has witnessed dramatic improvements in capabilities for identifying unknown compounds using high-resolution mass spectrometry (HRMS) and non-targeted analysis (NTA) approaches. Complementary developments in cheminformatics tools have further enabled an increase in NTA throughput and identification confidence. Together with the expanding availability of HRMS instrumentation in monitoring laboratories, these advancements make NTA highly relevant to rapid response scenarios. In this article, we introduce the concept of NTA as it relates to rapid response needs and describe how it can be applied to address unknown chemical releases. We advocate for the consideration of HRMS-based NTA approaches to support future rapid response scenarios. Environ Toxicol Chem 2021;00:1-14. Published 2021. This article is a U.S. Government work and is in the public domain in the USA.

Automated summary

Unknown chemical releases are a major focus of rapid response scenarios for the US Environmental Protection Agency. Recent advancements in high-resolution mass spectrometry and non-targeted analysis have significantly improved the ability to identify unknown compounds quickly and effectively, making them highly relevant in rapid response situations. This article advocates for the consideration of high-resolution mass spectrometry-based non-targeted analysis approaches to support future rapid response needs.