title: Non-target screening with high-resolution mass spectrometry: critical review using a collaborative trial on water analysis.
abstract: In this article, a dataset from a collaborative non-target screening trial organised by the NORMAN Association is used to review the state-of-the-art and discuss future perspectives of non-target screening using high-resolution mass spectrometry in water analysis. A total of 18 institutes from 12 European countries analysed an extract of the same water sample collected from the River Danube with either one or both of liquid and gas chromatography coupled with mass spectrometry detection. This article focuses mainly on the use of high resolution screening techniques with target, suspect, and non-target workflows to identify substances in environmental samples. Specific examples are given to emphasise major challenges including isobaric and co-eluting substances, dependence on target and suspect lists, formula assignment, the use of retention information, and the confidence of identification. Approaches and methods applicable to unit resolution data are also discussed. Although most substances were identified using high resolution data with target and suspect-screening approaches, some participants proposed tentative non-target identifications. This comprehensive dataset revealed that non-target analytical techniques are already substantially harmonised between the participants, but the data processing remains time-consuming. Although the objective of a "fully-automated identification workflow" remains elusive in the short term, important steps in this direction have been taken, exemplified by the growing popularity of suspect screening approaches. Major recommendations to improve non-target screening include better integration and connection of desired features into software packages, the exchange of target and suspect lists, and the contribution of more spectra from standard substances into (openly accessible) databases. Graphical Abstract Matrix of identification approach versus identification confidence.
authors.affiliation: Eawag: Swiss Federal Institute for Aquatic Science and Technology, Überlandstrasse 133, 8600, Dübendorf, Switzerland, emma.schymanski@eawag.ch.
authors.forename: Emma L
authors.initials: EL
authors.lastname: Schymanski
authors.forename: Heinz P
authors.initials: HP
authors.lastname: Singer
authors.forename: Jaroslav
authors.initials: J
authors.lastname: Slobodnik
authors.forename: Ildiko M
authors.initials: IM
authors.lastname: Ipolyi
authors.forename: Peter
authors.initials: P
authors.lastname: Oswald
authors.forename: Martin
authors.initials: M
authors.lastname: Krauss
authors.forename: Tobias
authors.initials: T
authors.lastname: Schulze
authors.forename: Peter
authors.initials: P
authors.lastname: Haglund
authors.forename: Thomas
authors.initials: T
authors.lastname: Letzel
authors.forename: Sylvia
authors.initials: S
authors.lastname: Grosse
authors.forename: Nikolaos S
authors.initials: NS
authors.lastname: Thomaidis
authors.forename: Anna
authors.initials: A
authors.lastname: Bletsou
authors.forename: Christian
authors.initials: C
authors.lastname: Zwiener
authors.forename: María
authors.initials: M
authors.lastname: Ibáñez
authors.forename: Tania
authors.initials: T
authors.lastname: Portolés
authors.forename: Ronald
authors.initials: R
authors.lastname: de Boer
authors.forename: Malcolm J
authors.initials: MJ
authors.lastname: Reid
authors.forename: Matthias
authors.initials: M
authors.lastname: Onghena
authors.forename: Uwe
authors.initials: U
authors.lastname: Kunkel
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Schulz
authors.forename: Amélie
authors.initials: A
authors.lastname: Guillon
authors.forename: Naïke
authors.initials: N
authors.lastname: Noyon
authors.forename: Gaëla
authors.initials: G
authors.lastname: Leroy
authors.forename: Philippe
authors.initials: P
authors.lastname: Bados
authors.forename: Sara
authors.initials: S
authors.lastname: Bogialli
authors.forename: Draženka
authors.initials: D
authors.lastname: Stipaničev
authors.forename: Pawel
authors.initials: P
authors.lastname: Rostkowski
authors.forename: Juliane
authors.initials: J
authors.lastname: Hollender
mesh_terms: D002849:Chromatography, Gas; D002853:Chromatography, Liquid; D013058:Mass Spectrometry / Q000379:methods*; D014867:Water / Q000032:analysis*
chemical_list: D014867:Water