Determination of hydrophilic organic compounds in river water by GC/MS coupled with solid-phase extraction using activated carbon cartridge

A simple GC/MS method coupled with solid-phase extraction for the determination of four hydrophilic organic compounds in river water was developed. Target hydrophilic organic compounds were 1,4-dioxane, epichlorohydrin, 2-ethoxyethanol, and N,N-dimethylfolmamide. A 500 mL portion of a water sample spiked with surrogate standards was passed to one C-18 cartridge and two activated-carbon cartridges in series. A C-18 cartridge was used for to trap coexistent hydrophobic organic compounds, and activated-carbon cartridges were used for the preconcentration of hydrophilic organic compounds. A C-18 cartridge was removed and discarded. After elution with dichloromethane and enrichment with a gentle steam of nitrogen, hydrophilic organic compounds were determined by GC/MS. The detection and quantitation limits of hydrophilic organic compounds by the proposed method were 0.013 similar to 0.017 mu g/L and 0.034 similar to 0.045 mu g/L, respectively. Using the proposed method, the concentrations of hydrophilic organic compounds in river water sampled at 45 sites in Tochigi prefecture were determined. The results show that the range of concentrations of 1,4-dioxane was between ND and 7.5 mu g/L; N,N-dime thylfolmamide was between ND and 11 mu g/L. Epichlorohydrin and 2-ethoxyethanol were not detected.