Content area
Full Text
Anal Bioanal Chem (2013) 405:29232929 DOI 10.1007/s00216-012-6446-0
ORIGINAL PAPER
Kinetic bromine isotope effect: example from the microbial debromination of brominated phenols
Anat Bernstein & Zeev Ronen & Elena Levin &
Ludwik Halicz & Faina Gelman
Received: 16 July 2012 /Revised: 13 September 2012 /Accepted: 20 September 2012 /Published online: 7 October 2012 # Springer-Verlag Berlin Heidelberg 2012
Abstract The increasing use of kinetic isotope effects for environmental studies has motivated the development of new compound-specific isotope analysis techniques for emerging pollutants. Recently, high-precision bromine isotope analysis in individual brominated organic compounds was proposed, by the coupling of gas chromatography to a multi-collector inductively coupled plasma mass spectrometer using strontium as an external spike for instrumental bias correction. The present study, for the first time, demonstrates an application of this technique for determining bromine kinetic isotope effects during biological reaction, focusing on the reductive debromination of brominated phenols under anaerobic conditions. Results show bromine isotope enrichment factors () of 0.760.08, 0.460.19, and 0.200.06 for the debromination of 4-bromophenol, 2,4-dibromophenol, and 2,4,6-tribromophenol, respectively. These values are rather low, yet still high enough to be obtained with satisfying certainty. This further implies that the analytical method may be also appropriate for future environmental applications.
Keywords Bromine . Isotope enrichment . GC-MC-ICPMS . CSIA
Introduction
In recent years, compound-specific isotope analysis has been introduced as a technique for elucidating degradation mechanisms and assessing the occurrence of degradation processes in complex environments [13]. The power of this concept has been demonstrated and it has become an important tool for analysis of contaminated sites [4]. Whereas analytical methods for 13C, 2H, and 15N analysis are
by now well established for many types of organic pollutants [2, 5], new techniques recently introduced for other elements such as chlorine [610] and sulfur [10, 11] still require their accreditation for analysis of common organic contaminants.
Bromine is another element of interest for environmental studies, since brominated organic compounds (BOC) are widespread environmental pollutants. Although some BOCs are produced naturally in the marine environment [12], much greater amounts of BOCs are entered into the environment as a result of anthropogenic activity (e.g., flame retardants, pesticides, drilling fluid additives) [13, 14]. Despite the fact that BOCs are rather widespread and can potentially be biode-graded (e.g., [15]),...