Application of solid-phase microextraction to the analysis of volatile organic compounds in water

Solid-phase microextraction (SPME) was investigated as a solvent-free alternative method for the extraction and analysis of some volatile organic compounds which can be present in industrial effluents. Such compounds are included in the hazardous pollutants list of the US National Institute for Occupational Safety and Health and the US Environmental Protection Agency. The performance of SPME fibres coated with two different stationary phases, such as poly(dimethylsiloxane) 100 mu m and 7 mu m film thickness and 85 mu m poly(acrylic acid) were evaluated. Absorption times of 12 min for 100-mu m poly(dimethylsiloxane) and 85-mu m poly(acrylic acid) fibres and 5 min for 7-mu m poly(dimethylsiloxane) were needed to reach the equilibrium and 2 min was enough for complete desorption of the analytes in the injection port of the gas chromatograph. High recoveries were obtained using the 100-mu m poly(dimethylsiloxane) fibre, although for polar compounds better results were found using the 85-mu m poly(acrylic acid) fibre. Linear dynamic ranges and a detection limit between 0.3 acid 1.5 mu g l(-1) were obtained using the 100-mu m poly(dimethylsiloxane) fibre and flame ionization detection. The SPME-GC procedure gave good repeatability (R.S.D.=4.3-10.5%) and reproducibility (R.S.D.=6.6-12.9%). The proposed SPME-GC method was applied to determine some volatile organic compounds in spiked drinking water and in industrial effluent samples.