Skip to content

Untargeted characterisation of dissolved organic matter contributions to rivers from anthropogenic point sources using direct infusion- and high-performance liquid chromatography-Orbitrap mass spectrometry

Research output: Contribution to journalArticle

Original languageEnglish
JournalRapid Communications in Mass Spectrometry
Early online date2 Nov 2019
DOIs
DateAccepted/In press - 25 Sep 2019
DateE-pub ahead of print (current) - 2 Nov 2019

Abstract

RATIONALE: Anthropogenic organic inputs to freshwaters can exert detrimental effects on aquatic ecosystems, raising growing concern for both environmental conservation and water security. Current regulation by the EU water framework directive (European Union, 2000/60/EC) relates to organic pollution by monitoring selected micropollutants, however, aquatic ecosystem responses requires a comprehensive understanding of dissolved organic matter (DOM) composition. The introduction of high-resolution mass spectrometry (HRMS) is set to greatly increase our understanding of the
composition of DOM of both natural and anthropogenic origin derived from diffuse and point sources.

METHODS: DOM was extracted from riverine and treated sewage effluent using solid phase extraction (SPE) and analysed using dissolved organic carbon (DOC) analysis, direct infusion-high resolution Orbitrap™ mass spectrometry (DI-HRMS) and high-performance liquid chromatography (HPLC/HRMS). The data obtained were analysed using univariate and multivariate statistics to demonstrate differences in background DOM, anthropogenic inputs and in-river mixing. Compound identifications were achieved based on MS2 spectra searched against on-line databases.

RESULTS: DI-HRMS spectra showed the highly complex nature of all DOM SPE extracts. Classification and visualisation of extracts containing many thousands of individual compounds were achieved using PCA and hierarchical cluster analysis. Kruskal-Wallis analyses highlighted significant discriminating ions originating from the sewage treatment works for more in-depth investigation by HPLC/HRMS. The generation of MS2 spectra in HPLC/HRMS provided the basis for identification of anthropogenic compounds including; pharmaceuticals, illicit drugs, metabolites and polymers, although many thousands of compounds remain unidentified.

CONCLUSIONS: This new approach enables comprehensive analysis of DOM in extracts without any preconceived ideas of the compounds which may be present. This approach has the potential to be used as a high throughput, qualitative, screening method to determine if the composition of point sources differs from that of the receiving water bodies, providing a new approach to the identification of hitherto unrecognised organic contribution to water bodies.

    Research areas

  • Dissolved organic matter, sewage effluent, DI-HRMS, HPLC-HRMS, data visualisation, difference algorithm

Documents

Documents

  • Full-text PDF (accepted author manuscript)

    Rights statement: This is the author accepted manuscript (AAM). The final published version (version of record) is available online via Wiley at https://onlinelibrary.wiley.com/doi/10.1002/rcm.8618. Please refer to any applicable terms of use of the publisher.

    Accepted author manuscript, 843 KB, PDF document

    Licence: CC BY

DOI

View research connections

Related faculties, schools or groups