The NORMAN Suspect List Exchange (NORMAN-SLE): facilitating European and worldwide collaboration on suspect screening in high resolution mass spectrometry
Authors: Mohammed Taha Hiba , Aalizadeh Reza , Alygizakis Nikiforos , Antignac Jean-Philippe , Arp Hans Peter H. , Bade Richard , Baker Nancy , Belova Lidia , Bijlsma Lubertus , Bolton Evan E. , Brack Werner , Celma Alberto , Chen Wen-Ling , Cheng Tiejun , Chirsir Parviel , Čirka Ľuboš , D’Agostino Lisa A. , Djoumbou Feunang Yannick , Dulio Valeria , Fischer Stellan , Gago-Ferrero Pablo , Galani Aikaterini , Geueke Birgit , Głowacka Natalia , Glüge Juliane , Groh Ksenia , Grosse Sylvia , Haglund Peter , Hakkinen Pertti J. , Hale Sarah E. , Hernandez Felix , Janssen Elisabeth M.-L. , Jonkers Tim , Kiefer Karin , Kirchner Michal , Koschorreck Jan , Krauss Martin , Krier Jessy , Lamoree Marja H. , Letzel Marion , Letzel Thomas , Li Qingliang , Little James , Liu Yanna , Lunderberg David M. , Martin Jonathan W. , McEachran Andrew D. , McLean John A. , Meier Christiane , Meijer Jeroen , Menger Frank , Merino Carla , Muncke Jane , Muschket Matthias , Neumann Michael , Neveu Vanessa , Ng Kelsey , Oberacher Herbert , O’Brien Jake , Oswald Peter , Oswaldova Martina , Picache Jaqueline A. , Postigo Cristina , Ramirez Noelia , Reemtsma Thorsten , Renaud Justin , Rostkowski Pawel , Rüdel Heinz , Salek Reza M. , Samanipour Saer , Scheringer Martin , Schliebner Ivo , Schulz Wolfgang , Schulze Tobias , Sengl Manfred , Shoemaker Benjamin A. , Sims Kerry , Singer Heinz , Singh Randolph R. , Sumarah Mark , Thiessen Paul A. , Thomas Kevin V. , Torres Sonia , Trier Xenia , van Wezel Annemarie P. , Vermeulen Roel C. H. , Vlaanderen Jelle J. , von der Ohe Peter C. , Wang Zhanyun , Williams Antony J. , Willighagen Egon L. , Wishart David S. , Zhang Jian , Thomaidis Nikolaos S. , Hollender Juliane , Slobodnik Jaroslav , Schymanski Emma L. 
Published: October 2022

Abstract
Background
The NORMAN Association (https://www.norman-network.com/) initiated the NORMAN Suspect List Exchange (NORMAN-SLE; https://www.norman-network.com/nds/SLE/) in 2015, following the NORMAN collaborative trial on non-target screening of environmental water samples by mass spectrometry. Since then, this exchange of information on chemicals that are expected to occur in the environment, along with the accompanying expert knowledge and references, has become a valuable knowledge base for “suspect screening” lists. The NORMAN-SLE now serves as a FAIR (Findable, Accessible, Interoperable, Reusable) chemical information resource worldwide.

Results
The NORMAN-SLE contains 99 separate suspect list collections (as of May 2022) from over 70 contributors around the world, totalling over 100,000 unique substances. The substance classes include per- and polyfluoroalkyl substances (PFAS), pharmaceuticals, pesticides, natural toxins, high production volume substances covered under the European REACH regulation (EC: 1272/2008), priority contaminants of emerging concern (CECs) and regulatory lists from NORMAN partners. Several lists focus on transformation products (TPs) and complex features detected in the environment with various levels of provenance and structural information. Each list is available for separate download. The merged, curated collection is also available as the NORMAN Substance Database (NORMAN SusDat). Both the NORMAN-SLE and NORMAN SusDat are integrated within the NORMAN Database System (NDS). The individual NORMAN-SLE lists receive digital object identifiers (DOIs) and traceable versioning via a Zenodo community (https://zenodo.org/communities/norman-sle), with a total of > 40,000 unique views, > 50,000 unique downloads and 40 citations (May 2022). NORMAN-SLE content is progressively integrated into large open chemical databases such as PubChem (https://pubchem.ncbi.nlm.nih.gov/) and the US EPA’s CompTox Chemicals Dashboard (https://comptox.epa.gov/dashboard/), enabling further access to these lists, along with the additional functionality and calculated properties these resources offer. PubChem has also integrated significant annotation content from the NORMAN-SLE, including a classification browser (https://pubchem.ncbi.nlm.nih.gov/classification/#hid=101).

Conclusions
The NORMAN-SLE offers a specialized service for hosting suspect screening lists of relevance for the environmental community in an open, FAIR manner that allows integration with other major chemical resources. These efforts foster the exchange of information between scientists and regulators, supporting the paradigm shift to the “one substance, one assessment” approach. New submissions are welcome via the contacts provided on the NORMAN-SLE website (https://www.norman-network.com/nds/SLE/).