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Sarah E Janssen

Sarah Janssen is an isotope geochemist working in the Mercury Research Lab (MRL) located within the Upper Midwest Water Science Center.

She has a PhD in environmental chemistry from Rutgers University and a bachelor’s in chemistry from
University of the Sciences in Philadelphia. Her work focuses on the application of stable isotope techniques for understanding sources and transformations of mercury (Hg) in the environment. Her research interests include Hg cycling in contaminated ecosystems, the investigation of microbial Hg transformations using stable isotopes, and development of analytical methods to improve Hg isotope measurements.


Current Projects

  • Mercury Cycling and Source Identification in the St Louis River Estuary MN/WI (collaboration with US EPA and Minnesota Pollution Control Agency)
  • Mercury Isotope Fractionation during Microbial Uptake and Transformations of Hg (collaboration with Rutgers University and University of Ottawa)
  • Method Development for the Pre-concentration of Waters and Low Concentration Environmental Samples for Mercury Isotopic Analysis