Authors: Stephanie Spahr Sebastian Huntscha Jakov Bolotin Michael P Maier Martin Elsner Juliane Hollender Thomas B Hofstetter
Publish Date: 2012/12/09
Volume: 405, Issue: 9, Pages: 2843-2856
Abstract
Compoundspecific isotope analysis CSIA is an important tool for the identification of contaminant sources and transformation pathways but it is rarely applied to emerging aquatic micropollutants owing to a series of instrumental challenges Using four different benzotriazole corrosion inhibitors and its derivatives as examples we obtained evidence that formation of organometallic complexes of benzotriazoles with parts of the instrumentation impedes isotope analysis Therefore we propose two strategies for accurate delta13C and delta15N measurements of polar organic micropollutants by gas chromatography isotope ratio mass spectrometry GC/IRMS Our first approach avoids metallic components and uses a Ni/Pt reactor for benzotriazole combustion while the second is based on the coupling of online methylation to the established GC/IRMS setup Method detection limits for oncolumn injection of benzotriazole as well as its 1CH 3 4CH 3 and 5CH 3substituted species were 01–03 mM and 01–10 mM for δ13C and δ15N analysis respectively corresponding to injected masses of 07–18 nmol C and 04–30 nmol N respectively The Ni/Pt reactor showed good precision and was very longlived 1000 successful measurements Coupling isotopic analysis to offline solidphase extraction enabled benzotriazoleCSIA in tap water wastewater treatment effluent activated sludge and in commercial dishwashing products A comparison of delta 13C and delta 15N values from different benzotriazoles and benzotriazole derivatives both from commercial standards and in dishwashing detergents reveals the potential application of the proposed method for source apportionment
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