Monitoring Water Quality by Passive Sampling and GC×GC–TOF MS with Variable-Energy Electron Ionisation

Poster Presentation

Prepared by N. Watson1, L. McGregor2, S. Smith2, A. Gravell3, G. Mills4
1 - Markes International, 11126 Kenwood Road, Cincinnati, OH, 45242, United States
2 - Markes International, Gwaun Elai Mediscience Campus, Llantrisant, RCT, CF728XL, United Kingdom
3 - National Resources Wales (NRW), National Resources Wales (NRW), Cross hands, Llanelli, Carmarthenshire, SA14 6RE, United Kingdom
4 - University of Portsmouth, School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, PO1 2UP, United Kingdom


Contact Information: nwatson@markes.com; 513-488-6161


ABSTRACT

Two-dimensional gas chromatography with time-of-flight mass spectrometry (GCxGC-TOF MS) can provide highly sensitive detection and confident mass spectral identification of pollutants within complex environmental extracts. Nevertheless, the identification of individual compounds may be hindered by weak molecular ions or when similar mass spectral characteristics are evident across entire chemical classes. Select-eV ion source technology overcomes this problem by allowing both hard and soft electron ionisation with no inherent loss in sensitivity. Select-eV provides enhanced molecular ions whilst retaining structurally-significant fragment ions, delivering both confident compound identification and increased selectivity. We show the potential of this technology for the analysis of both target pollutants and unknown chemicals in water.

Typically, environmental legislation covers the analysis of priority pollutants to monitor water quality, however, the screening of water samples for emerging contaminants, such as disinfectant by-products, is becoming of increasing importance. Passive sampling devices (e.g. semi-permeable membrane devices (SPMD), LDPE and silicone rubber) are often used for this purpose. The samplers were deployed for several weeks in a polluted river course in the UK to effectively sequester large volumes of water and provide a concentrated, representative extract for analysis by GCxGC-TOF MS with Select-eV.

This work shows the suitability of this novel analytical platform for environmental investigations, using both target-focused studies as well as non-targeted routines for screening for the presence of emerging contaminants, such as polycyclic musks from personal care products.