What’s That Smell? Trace-Level Analysis of Odorants in Water Using High-Capacity Sorptive Extraction

New Organic Monitoring Techniques
Oral Presentation

Prepared by R. Harrington1, J. Mayser2, N. Shafer3, R. Szafnauer4, R. Cole4, G. Burr5, B. Peterson5
1 - Aquaculture Research Institute, 17 Godfrey Dr., University of Maine, Oono, Maine, 04473, United States
2 - Markes International GmbH, Bieberer Straße 1-7, Offenbach am Main, 63065, Germany
3 - Markes International Inc., 2355 Gold Meadow Way, Sacramento, California, 95670, United States
4 - Markes International Ltd, 1000B Central Park, Western Avenue, Bridgend, CF31 3RT, United Kingdom
5 - USDA-ARS-National Cold Water Marine Aquaculture Center, 25 Salmon Farm Road, Franklin, Maine, 04634, United States


Contact Information: [email protected]; +491722819658

ABSTRACT

Volatile organic compounds (VOCs) in drinking and environmental waters at trace-levels can negatively affect consumer experience. Naturally occurring compounds such as geosmin, have particularly strong odours and are often the source of complaints to water companies, while other emerging odorants (e.g., isobutyl methoxypyrazine, IBMP) are also of concern.
In aquaculture, recirculating aquaculture systems (RAS) used for rearing fish on land to meet commercial demands for human consumption, require routine monitoring of the recycled water for odorous compounds too. The use of continually recycled water leaves these systems susceptible to colonisation by odorant-producing microbes and so, fish from affected systems acquire an unpleasant odour and taste, negatively affecting fish quality.
Reliable detection of these compounds is therefore important, but challenged by their low odour thresholds, at the low ng/L level. This study focuses on five malodorous compounds, which include geosmin and 2-methylisoborneol, that are measured across international regulations, which have been regularly associated with pelagic and benthic harmful algal blooms.
Using robust and fully automated high-capacity sorptive extraction (HiSorb), combined with analyte preconcentration on a cryogen-free focusing trap, low levels of odorants in water can be analysed, while maintaining peak shape, for increased signal-to-noise response, excellent linearity, low detection limits and highly reproducible results. The low detection limits enable water distribution facilities and producers using RAS to detect malodorous compounds before consumers, allowing corrective action to be taken earlier.