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Structure identification approaches using the US EPA CompTox Chemicals Dashboard to support mass spectrometry analyses
Citation:
Williams, A., C. Lowe, A. Chao, E. Ulrich, AND J. Sobus. Structure identification approaches using the US EPA CompTox Chemicals Dashboard to support mass spectrometry analyses. 262nd ACS National Meeting & Exposition, Atlanta, Georgia, August 22 - 26, 2021. https://doi.org/10.23645/epacomptox.16512258
Impact/Purpose:
The US-EPA Center for Computational Toxicology and Exposure (CCTE) has been generating data and building software applications and web-based chemistry databases for over a decade. To support our efforts to develop new approaches to prioritize chemicals based on potential human health risks, we aggregate and curate data streams of various types to support prediction models. Suspect, Targeted and Non-targeted Analysis mass spectrometry approaches all utilize the CompTox Chemicals Dashboard and associated meta-data streams. Advanced search capabilities supporting mass spectrometry based data analysis (all forms of targeted and non-targeted analysis) to support data required for more quantitative exposure modeling are delivered with this product. This includes mass spectral data searching of experimental versus predicted data and other advanced candidate ranking approaches. The results of these efforts will be of direct benefit to program and regional offices as well as the greater scientific community.
Description:
High resolution mass spectrometry (HRMS) and non-targeted analysis (NTA) are utilized to identify emerging contaminants and chemical signatures of interest detected in various media. At the US Environmental Protection Agency the CompTox Chemicals Dashboard (https://comptox.epa.gov/dashboard) is an open chemistry resource and web-based application containing data for ~900,000 substances and supports non-targeted and suspect screening analyses. Searching functionality includes identifier searches (e.g. systematic names, trade names and CAS Registry Numbers), mass and formula-based searches and prototype developments include combined substructure-mass/formula searches and searching experimental mass spectral data against predicted fragmentation spectra. A specific type of data mapping in the database uses “MS-Ready” structures, a way to process all registered substances to separate multi-component chemicals into their individual components, removal of stereochemical bonds and desalting and neutralization. This MS-Ready processing supports batch-searching using either mass or formulae to identify candidate chemicals and their mapped substances. A number of chemical lists (https://comptox.epa.gov/dashboard/chemical_lists) have also been developed to support the identification of chemicals related to agrochemistry, specifically pesticides (both active and inert constituents), insecticides and their metabolites and environmental breakdown products). This presentation will provide an overview of how the CompTox Chemicals Dashboard supports mass spectrometry based structure identification and non-targeted analysis of chemicals in agrochemistry. This abstract does not necessarily represent the views or policies of the U.S. Environmental Protection Agency
URLs/Downloads:
DOI: Structure identification approaches using the US EPA CompTox Chemicals Dashboard to support mass spectrometry analyses
NTA MASS SPECTROMETRY TARGETED AND NON-TARGETED ANALYSIS_AGRO_V2.PDF (PDF, NA pp, 7548.636 KB, about PDF)