1. Department of Analytical Chemistry, Helmholtz Centre for Environmental Research—UFZ, Permoserstrasse 15, D-04318 Leipzig, Germany
2. Bioforsk, Norwegian Institute for Agricultural and Environmental Research, Postveien 213, N-4353 Klepp st., Norway
3. Institute of Chemistry, Food Chemistry
and Environmental Chemistry, Martin-Luther-University Halle-Wittenberg, Kurt-Mothes-Strasse 2, D-06120 Halle
(Saale), Germany