Measurement of trihalomethanes in potable and recreational waters using solid phase micro extraction with gas chromatography-mass spectrometry

Solid phase micro extraction (SPME) was applied to the determination of selected trihalomethanes (THMs), chloroform, bromodichloromethane, dibromochloromethane, bromoform, in potable and recreational waters. The selected samples were environmentally significant due to mandatory limits imposed by regulatory agencies. Extraction of the analytes was performed using headspace SPME (fused silica fibre with a 100 μm poly(dimethylsiloxane coating) followed by thermal desorption at 220°C and GC-MS analysis. A linear working range of 10–160 μg/l was established with relative standard deviations (%RSD) within the range, 0.9–19%. Limits of detection (LOD) were 1.0–2.8 μg/l. The highest THM concentration was 61.8 μg/l which was well within the proposed European Union directive of 100 μg/l. The total THMs determined in swimming pool waters ranged from 105–134 μg/l, with chloroform accounting for 84–86% of total THM.