1. Organic Analytical Chemistry, University of Basel, Neuhausstr. 31, CH-4057 Basel, Switzerland, and Centre for Indigenous Peoples' Nutrition and Environment (CINE) and School of Dietetics and Human Nutrition, Macdonald Campus of McGill University, 21,111 Lakeshore Road, Ste-Anne-de-Bellevue, Quebec H9X 3V9, Canada