Postdoc in Environmental Chemistry / Gut Microbiolgy

The position is a postdoctoral research appointment at the University of Bern, focusing on environmental chemistry and gut microbiology. The project investigates whether the arsenic compound arsenobetaine, abundant in fish and seafood, can be converted by the human gut microbiota into more toxic arsenic species, a question that matters for risk assessment and regulatory evaluation by bodies such as FSVO and EFSA. Daily work will involve creating and validating analytical protocols to track arsenobetaine transformation in fecal samples, using extraction techniques and a suite of arsenic speciation methods based on HPLC‑ICP‑MS/MS. The researcher will design robust experiments, cultivate human fecal microbiota from ongoing cohort studies, screen for conversion events, test realistic exposure conditions, and probe microbial factors that influence the process. Additional duties include preparing reports, drafting manuscripts, delivering scientific talks, and assisting with HPLC‑ICP‑MS troubleshooting in the laboratory. Candidates must hold a PhD in environmental or analytical chemistry or a closely related discipline and have demonstrable experience with hyphenated analytical methods. Independent operation of HPLC‑ICP‑MS for trace‑element speciation in non‑water matrices is essential, and prior work on arsenic speciation is preferred. Strong English writing and presentation skills, a record of publications, and the ability to work collaboratively, precisely, and autonomously in an interdisciplinary setting are required. Beneficial expertise includes statistical analysis and data visualisation, method development or troubleshooting for HPLC‑ICP‑MS, and experience with microbiology incubations. Applications should consist of a one‑page motivation letter, a CV, and two referee contacts, submitted as a single PDF by 30 September 2026.