Simultaneous determination of halogenated neutral and acidic disinfection by-products in drinking water by closed-loop stripping extraction and capillary gas chromatography.

The analytical capabilities of Grob closed-loop stripping analysis technique were evaluated for the determination, in drinking water, of trihalomethanes, haloacetonitriles, haloacetic acids, chloropicrin, halogenated ketones and chloral hydrate, reported as chlorination disinfection by-products. Thus by one-step enrichment and isolation procedure and subsequent analysis by capillary gas chromatography with electron-capture detection, organic polar and non-polar disinfection by-products could be analyzed at levels as low as 0.5 ng/l for trihalomethanes, 1 ng/l for haloacetonitriles and 45-72 ng/l for haloacetic acids.