Methods validation for the determination of trihalomethanes in drinking water

Trihalomethanes (THMs), chlorinated by-products in drinking water, have been determined by comparing some analytical methods, based on the following techniques: liquid-liquid extraction-gas chromatography-mass spectrometry (LLE-GC-MS), headspace-gas chromatography-mass spectrometry (headspace-GC-MS) and purge and trap-gas chromatography-mass spectrometry (PT-GC-MS). The mass spectrometer was operated in the SIM mode. The quantitative methods were validated and compared to the ability to identify and to measure reliably the yields of the toxic compounds. Good validation parameters were obtained for each method.