The determination of six taste and odour compounds in water using Ambersorb 572 and high resolution mass spectrometry

A method for the analysis of six taste and odour causing compounds in aqueo us samples using the granular adsorbent, Ambersorb 572, and gas chromatogra phy-high resolution mass spectrometry (GC-HRMS) has been developed. This me thod for the determination of geosmin, 2-methylisoborneol (2-MIB), 2-isopro pyl-3-methoxypyrazine (IPMP), 2-isobutyl-3-methoxypyrazine (IBMP), 2,3,6-tr ichloroanisole (236-TCA) and 2,4,6-trichloroanisole (246-TCA) is highly pro ductive [up to 40 samples per day + 23 quality control (QC) samples] and pr ovides rapid (24-48 h) turnaround times. The analytes are extracted from wa ter by the addition of Ambersorb 572 to the sample bottle and rolling for 1 h. The adsorbent is isolated by filtration and allowed to air dry for 1 h. The Ambersorb 572 is transferred to an autosampler vial and the analytes a re desorbed into dichloromethane. The extract is analysed by GC-HRMS at 700 0 resolving power (RP). Quantification is performed by isotope dilution and internal standard techniques utilizing d(3)-geosmin, d(3)-2-MIB, d(5)-246- TCA and 2-sec-butyl-3-methoxypyrazine (s-BMP). Method precisions of 3.5-5.8 % and accuracies of +/-5.7-8.9% were obtained. Reporting detection limits ( RDLs) of 1.0 ng L-1 were obtained for 2-MIB, geosmin, IPMP and IBMP, while RDLs of 2.0 ng L-1 were obtained for 236-TCA and 246-TCA.