An assessment of Quality Assurance/Quality Control Efforts in High Resolution Mass Spectrometry Non-Target Workflows for Analysis of Environmental Samples

The application of non-target analysis (NTA), a comprehensive approach to characterize unknown chemicals, including chemicals of emerging concern has seen a steady increase recently. Given the relative novelty of this type of analysis, robust quality assurance and quality control (QA/QC) measures are imperative to ensure quality and consistency of results obtained using different workflows. Due to fundamental differences to established targeted workflows, new or expanded approaches are necessary; for example to minimize the risk of losing potential substances of interest (i.e. false negatives, Type II error). We present an overview of QA/QC techniques for NTA workflows published to date, specifically focusing on the analysis of environmental samples using liquid chromatography coupled to HRMS. From a QA/QC perspective, we discuss methods used for each step of analysis: sample preparation, chromatography, mass spectrometry, and data processing, and finish with a series of recommendations to improve the quality assurance of NTA workflows.