A fast stir bar sorptive extraction method for the analysis of geosmin and 2-methylisoborneol in source and drinking water.
The presence of unpleasant taste and odour in drinking water is an ongoing aesthetic concern for water providers worldwide. The need for a sensitive and robust method capable of analysis in both natural and treated waters is essential for early detection of taste and odour events. The purpose of this study was to develop and optimise a fast stir bar sorptive extraction (SBSE) method for the analysis of geosmin and 2-methylisoborneol (MIB) in both natural water and drinking water. Limits of detection with the optimised fast method (45 min extraction time at 60 degrees C using 24 microL stir bars) were 1.1 ng/L for geosmin and 4.2 ng/L for MIB. Relative standard deviations at the detection limits were under 17% for both compounds. Use of multiple stir bars can be used to decrease the detection limits further. The use of 25% NaCl and 5% methanol sample modifiers decreased the experimental recoveries. Likewise, addition of 1 mg/L and 1.5 mg/L NaOCI decreased the recoveries and this effect was not reversed by addition of 10% thiosulphate. The optimised method was used to measure geosmin concentrations in treated and untreated drinking water. MIB concentrations were below the detection limits in these waters.
Bauld
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T
School of Environmental and Applied Science, Griffith University Gold Coast Campus, Gold Coast Mail Centre, Old 9726, Australia. tamarabauld@hotmail.com
Teasdale
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P
Stratton
H
H
Uwins
H
H
D000042:Absorption; D001892:Camphanes / Q000032:analysis* / Q000302:isolation & purification*; D002713:Chlorine / Q000032:analysis; D004784:Environmental Monitoring / Q000379:methods; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D015233:Models, Statistical; D009284:Naphthols / Q000032:analysis* / Q000302:isolation & purification*; D009812:Odorants; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013696:Temperature; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000032:analysis; D018508:Water Purification / Q000379:methods; D014881:Water Supply
D001892:Camphanes; D009284:Naphthols; D014874:Water Pollutants, Chemical; C005536:2-methylisoborneol; D002713:Chlorine; C001278:geosmin