Application of different analytical methods for determination of volatile chlorination by-products in drinking water

Four analytical methods have been applied for the determination of volatile chlorination by-products in drinking water, based on the following techniques: liquid–liquid extraction–gas chromatography–electron capture detection (LLE–GC–ECD); liquid–liquid extraction–gas chromatography–mass spectrometry (LLE–GC–MS); purge and trap–gas chromatography–mass spectrometry (purge and trap–GC–MS); and headspace-gas chromatography–mass spectrometry (headspace–GC–MS). The compounds studied were trihalomethanes, haloacetonitriles, haloketones, chloral hydrate and chloropicrin. LLE–GC–ECD method proved to be the most sensitive for determination of all compounds studied, followed by LLE–GC–MS. Purge and trap–GC–MS method gave good results in the case of trihalomethanes, but had high detection limits for the other volatile chlorination by-products. Headspace–GC–MS method had acceptable recoveries for trihalomethanes, but the detection limits were higher.