Solid-phase microextraction for the determination of iodinated trihalomethanes in drinking water

A headspace solid-phase microextraction (HS-SPME) method has been developed for the determination of iodinated trihalomethanes (ITHMs) in treated wate r samples. Mixed THMs (bromochloroiodo-, bromodiiodo-, chlorodiiodo-, dibro moiodo- and dichloroiodo-) were previously synthesized since commercial sta ndards are not available. HS-SPME has shorter equilibration times than dire ct SPME, a cleaner background and a longer fiber life. Experimental paramet ers such as the selection of SPME coatings, sample volume, extraction time and addition of salts were studied. The Carbowax-divinylbenzene fiber appea rs to be the most suitable for the determination of ITHMs. Analytical param eters such as linearity, limit of detection and precision were also evaluat ed. HS-SPME was compared to liquid-liquid microextraction for the analyses of spiked treated water samples, obtaining a good agreement. It is conclude d that HS-SPME has a great potential for drinking water analysis. (C) 1999 Elsevier Science B.V. All rights reserved.