Development of a Comprehensive Analytical Method for Semi-volatile Organic Compounds in Water Samples by a Combination of Solid-phase Extraction and Gas Chromatography-mass Spectrometry Database System

Abstract

Summar y A comprehensive analytical method for semi-volatile organic compounds (SVOCs) in water samples by a combination of solid-phase extraction (SPE) and the automated identification and quantification system for gas chromatography-mass spectrometry database (AIQS-DB) has been developed. In the examinations of method development, 202 model compounds (MCs) that represent SVOCs that can be measured with GC-MS were used. Two SPE cartridges of hydrophilic functional group introduced styrenedivinylbenzene (SDB) polymer and activated carbon were selected as a best SPE combination and pH 7． 0 was selected as the optimum extraction pH. In the reagent water recovery test (0． 1 µg/L), the SPE method showed 96 % of the average recovery for 193 MCs, and that was comparable to 94 % of the average recovery shown by liquid-liquid extraction with dichloromethane (DCM-LLE). The method detection limit of the developed SPE method was 0． 029 µg/L in average. In the recovery tests (0． 1 µg/L) using seawater, river water and a sewage treatment facility effluent, the SPE method was able to extract 184 MCs (51 classes. logPow-0． 65-15． 07, b.p. 145-536 ℃) with 90 % of the average recovery except for high polar substances such as aromatic amines. To confirm the recoveries of such low recovery compounds, 17 surrogates were employed. Finally the combination of the SPE method and AIQS-DB was applied to real samples and the results were compared with those by the combination of DCM-LLE and AIQS-DB. As a result, the developed method detected 39 substances with a wide-range physico-chemical properties (logPow-0． 07-14． 6, b.p. 176-404 ℃) which were the same as those by DCM-LLE. The detected concentrations by the both methods were almost the same except for sterols, bisphenol A and aniline that were highly extracted by DCM-LLE. From these results , it was demonstrated that SVOCs comprised of a wide range of volatility and polarity were able to be simultaneously extracted and determined by the combination of the developed SPE method and AIQS-DB.