Creation of an Open-Access High-Resolution Tandem Mass Spectral Library of 1000 Food Toxicants

Spectral library searching is a key method for compound annotation in mass spectrometry; however, existing libraries often suffer from high data heterogeneity, varying spectral quality, or limited accessibility. These issues are particularly significant in food safety, where the lack of comprehensive reference data hampers the identification of hazardous compounds. To address these limitations, we developed the WFSR Food Safety Mass Spectral Library, a freely accessible tandem mass spectral library focused on food contaminants, residues, and hazardous compounds. This library contains 6993 manually curated spectra from 1001 compounds acquired in positive ionization mode using ultrahigh-performance liquid chromatography coupled to an Orbitrap IQ-X Tribrid mass spectrometer. Spectra were recorded at seven collision energies under standardized conditions. Comprehensive metadata are provided, including common names, CAS, SMILES, InChIKeys, retention times, and compound classes. The library is publicly available via a dedicated website (https://www.wur.nl/en/show/food-safety-mass-spectral-library.htm) and through the GNPS repository, adhering to FAIR data principles to facilitate community reuse. Comparisons with major repositories (GNPS, MassBank, MoNA, and MSnLib) showed that 216 compounds (22.2%) are unique to our library. Further analysis using molecular networking and MS2Query revealed that about 38% of the compounds lack reliable matches in public libraries. The WFSR spectral library is designed to improve the annotation of food toxicants and facilitate the identification of structural analogues using computational tools. This library is part of an ongoing initiative with future updates planned to include negative ionization mode spectra and an expanded compound repertoire, aiming to advance food safety monitoring.