Reactive Organic Pollutants (ROP's)
The list of persistent organic pollutants (POPs) regulated under the Stockholm Convention is growing and new candidates are insight, fulfilling the criteria on persistence, toxicity, long-range transport- and bio-accumulation potential. Some of these POPs have been produced at large scales (>10'000 t/y) and were distributed globally. With mass spectrometric methods, they can be detected in materials, food, feed and are now ubiquitous in the environment.
In 2017, short-chain chlorinated paraffins (SCCPs) have been included to the Stockholm Convention POP list and their use as plastic additives was discontinued. Alternative products are now longer-chain CPs, which we frequently found in many plastic consumer products of the Swiss market.
In the CP-MAT project, it is our goal to develop new standard materials and selective analytical methods based on ultra-high resolution mass spectrometry (R > 60'000) to detect and quantify longer-chain CPs in plastic materials.
Partners are BAFU, Swiss Cantonal Labs, University of Zürich.
- L. Schinkel, E. Canonica, P. Lienemann, D. Bleiner. N. V. Heeb, Mass spectrometric analysis of short-chain chlorinated paraffins in plastic consumer products, Chimia, 73, 504, 2019.
- L. Schinkel, C. Bogdal, E. Canonica, R. Cariou, K. McNeill, D. Bleiner, N. V. Heeb, The urgent need for more specific reference materials for the analysis of medium-chain and long-chain chlorinated paraffins, , Environmental Science & Technology Letters, 2018, 5, 708-717.
- L. Schinkel, S. Lehner, N. V. Heeb, P. Lienemann, K. McNeill, C. Bogdal, Deconvolution of mass spectral interferences of chlorinated alkanes and their thermal degradation products: chlorinated alkenes, Analytical Chemistry, 89, 5924-5932, 2017.
Norbert Heeb studied chemistry at the ETH Zürich. In 1991, he earned his PhD at the ETH Zürich in the Institute of Organic Chemistry in Prof. Steven Benner's group. After post-doctoral studies at the University of California in Davis, he joined the Laboratory of Organic Chemistry at Empa in 1993. His current research activities at Empa are in the field of applied catalysis, studying transformation reactions of pollutants in current and future catalytic converter technologies such as particle filters, deNOx- and combined filter-deNOx systems. The release and transformation of pollutants from materials like plastic, increasingly also from recycled materials, during production, use and disposal are another active field of research. Mass spectrometry in combination with various ionization techniques, coupled to chromatographic methods are the methods of choice to tackle these analytical tasks. Norbert Heeb contributed to 86 peer-reviewed papers (43 first author) and more than 150 oral and poster presentations at international conferences. In 2009, he received the Sandmeyer Prize of the Swiss Chemical Society for his research on particle filter chemistry. He has supervised 24 bachelor-, master- and doctoral theses and co-organized 23 national and international conferences.
- N. V. Heeb, W.B. Schweizer, M. Kohler and A.C. Gerecke, Structure elucidation of hexabromocyclododecanes - a class of compounds with a complex stereochemistry, in Chemosphere, 61, 65-73, 2005. (152 citations)
- N. V. Heeb, A.-M. Forss, S. Brühlmann, R. Lüscher, C. J. Saxer, P. Hug, Three-way catalyst-induced formation of ammonia - velocity- and acceleration-dependent emission factors, Atmospheric Environment, 40, 5986-5997, 2006. (102 citations)
- N. V. Heeb, P. Schmid, M. Kohler, E. Gujer, M. Zennegg, D. Wenger, A. Wichser, A. Ulrich, U. Gfeller, P. Honegger, K. Zeyer, L. Emmenegger, J.-L. Petermann, J. Czerwinski, T. Mosimann, M. Kasper, A. Mayer, Secondary effects of catalytic diesel particulate filters: Conversion of PAHs versus formation of Nitro-PAHs, Environmental Science & Technology, 42, 3773-3779, 2008. (93 citations)
- N. V. Heeb, C. J. Saxer, A.-M. Forss, S. Brühlmann, Reactive nitrogen compounds in vehicle exhaust: Trends of NO, NO2, and NH3 emissions from gasoline-fueled Euro-3 to Euro-4 passenger cars, Atmospheric Environment, 42, 2543-2554, 2008. (82 citations)
- N. V. Heeb, W. B. Schweizer, P. Mattrel, R. Haag, A. C. Gerecke, P. Schmid, M. Zennegg, H. Vonmont, Regio- and stereoselective isomerization of hexabromocyclododecanes (HBCDs): Kinetics and mechanism of g- to a-HBCD isomerization, Chemosphere, 73, 1201-1210, 2008. (65 citations)
Persistent Organic Pollutants (POP's) at Ultratrace Level
High resolution is one of the main benefits for the small molecule analysis provided by Orbitrap FTMS. Direct infusion without on-line separation, on-line separation using liquid chromatography (LC) and gas chromatography (GC), as well as surface imaging are all widely employed sample ionization and introduction approaches for hyphenation with Orbitraps. The limitations may include a moderate throughput (higher resolution means longer ion detection), a certain care being required to provide accurate isotopic abundance ratios, restricted increase of the resolution for achieving isotopic fine structure information and separating isobaric compounds at high mass, and, perhaps most importantly, a sensitivity.
For example, trace level quantitatively-accurate measurements of organic pollutants, for example dioxins in biofluids, are essential for monitoring of the environmental hazards and timely initiating personal preventive care. However, a single measurement of a low concentration sample using GC Orbitrap FTMS may be not sensitive enough to detect the compounds of interests or to accurately quantify their levels. The fundamental nature of FTMS suggests a possible way of increasing the sensitivity of targeted and untargeted analysis for both isolated compounds and those embedded into a complex matrix, by averaging of time-domain unprocessed data (transients) across a number of technical replicates from GC-MS measurements, followed by Fourier transformation. A principal obstacle to realize this approach is the absence of an access to the transient signals from Orbitrap FTMS instruments.
We developed an implementation of a transient-recording capability on the GC Orbitrap FTMS and further method development and application for increasing the sensitivity of the trace level persistent organic pollutant analysis.
Preliminary results demonstrate that a multiplexed GC-MS approach is beneficial for the increased sensitivity and improved accuracy in the quantitative analysis of low abundant dioxins. Furthermore, with an available access to the transients, we were able to significantly increase the overall resolution obtainable from the GC Orbitrap FTMS by recording transients with 2-10 fold extended duration. That proportionally (linearly) increased the maximum achievable resolution in mass spectra. As a result, an isotopic fine structure analysis, which can aid in targeted and untargeted molecular analysis, has been uniquely enabled on the GC Orbitrap FTMS. Comparable advantages have been demonstrated for other applications, including for multiplexed quantitative lipidomics using direct infusion FTMS, LC-MS hyphenation, and imaging of biological tissues.
Project leader and project partner in different research projects for several national authorities and universities. Supervision of trainee, graduates and PhD students in the Laboratory for Advanced Analytical Technologies. Guest lecturer for environmental chemistry and environmental risk assessment at the university of applied sciences Zürich (ZHAW / Bachelor Degree) and university of applied sciences northwestern Switzerland in Basel (FHNW / Master Degree). Invited lectures at university seminars, national and international conferences.
- Nagornov, K.O., Zennegg, M., Kozhinov, A.N., Tsybin, Y.O., Bleiner, D. Trace-Level Persistent Organic Pollutant Analysis with Gas-Chromatography Orbitrap Mass Spectrometry-Enhanced Performance by Complementary Acquisition and Processing of Time-Domain Data (2020) Journal of the American Society for Mass Spectrometry, 31 (2), pp. 257-266.
- Strobel, A., Schmid, P., Burkhardt-Holm, P., Segner, H., Zennegg, M. Persistent organic pollutants in red- and white-blooded High-Antarctic notothenioid fish from the remote Weddell Sea (2018) Chemosphere, 193, pp. 213-222.
- Zennegg, M., Schluep, M., Streicher-Porte, M., Lienemann, P., Haag, R., Gerecke, A.C. Formation of PBDD/F from PBDE in electronic waste in recycling processes and under simulated extruding conditions (2014) Chemosphere, 116, pp. 34-39.
- Zennegg, M., Munoz, M., Schmid, P., Gerecke, A.C. Temporal trends of persistent organic pollutants in digested sewage sludge (1993-2012) (2013) Environment International, 60, pp. 202-208.
- Sorg, O., Zennegg, M., Schmid, P., Fedosyuk, R., Valikhnovskyi, R., Gaide, O., Kniazevych, V., Saurat, J.-H. 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) poisoning in Victor Yushchenko: identification and measurement of TCDD metabolites (2009) The Lancet, 374 (9696), pp. 1179-1185.