Trace Analysis of Isothiazolinones in Water Samples by Large-Volume Direct Injection Liquid Chromatography Tandem Mass Spectrometry

The work outlined in this poster is, to the best of the authors knowledge,  the first employing LC–MS/MS for the analysis of some of the isothiazolinones. Second, it shows that direct on-column injection of relatively large volumes (mL range) of non-pretreated aqueous samples can be applied when using HPLC stationary phases that are amenable to high water contents (up to 100%) of the sample introduced. The results of the analyses of environmental water samples confirm earlier findings that the levels of the isothiazolinones in the aquatic environment are such that, despite their large volumes of production, they probably do neither pose an environmental nor a human health risk. The analytical method described can be used for checking the presence of preservatives in membrane flushings and in produced water, in line with the European standard EN 12873-4.