Janssen, S.E.; Johnson, M.W.; Blum, J.D.; Barkay, T.; Reinfelder, J.R., Separation of monomethylmercury from estuarine sediments for mercury isotope analysis. Chemical Geology 2015
Sarah E Janssen
Biography
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.
Education
Ph.D. 2016, Environmental Chemistry, Rutgers University, New Brunswick, NJ
B.S. 2011, Chemistry, University of the Sciences, Philadelphia, PA
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
Science and Products
Date published: October 11, 2019
Status: Completed Mercury Isotope Ratios used to Determine Sources of Mercury to Fish in Northeast U.S. Streams
Mercury isotope analyses were used to distinguish different sources of mercury to fish in 23 streams along a forested-rural to urban-industrial land-use gradient in the Northeastern United States. The use of mercury isotope measurements in fish tissue allow for distinguishing different sources of mercury that are bioaccumulating into the food web. Mercury isotope signatures in fish in forested...
Contacts: David P Krabbenhoft, Sarah E Janssen
Date published: April 11, 2019
Status: Active Mercury studies
The USGS Mercury Research Lab is a national leader in advancing mercury research and science, specializing in low-level mercury speciation and isotope analysis and mercury-source fingerprinting. The MRL leads national cutting-edge collaborative studies, including state-of-the-art sample analysis, methods development for field and lab procedures, and data interpretation and dissemination.
Contacts: Sarah E Janssen, David P Krabbenhoft
Year Published: 2021
The influence of legacy contamination on the transport and bioaccumulation of mercury within the Mobile River Basin
Past industrial use and subsequent release of mercury (Hg) into the environment have resulted in severe cases of legacy contamination that still influence contemporary Hg levels in biota. While the bioaccumulation of legacy Hg is commonly assessed via concentration measurements within fish tissue, this practice becomes difficult in regions of high...
Janssen, Sarah E.; Tate, Michael T.; Krabbenhoft, David P.; DeWild, John F.; Ogorek, Jacob M.; Babiarz, Christopher L.; Sowers, Anthony; Tuttle, Peter L.Attribution: Upper Midwest Water Science Center
Year Published: 2020
Insights into mercury source identification and bioaccumulation using stable isotope approaches in the Hannibal Pool of the Ohio River
Mercury contamination in river systems due to historic and current Hg releases is a persistent concern for both wildlife and human health. In larger rivers, like the Ohio River, USA, it is difficult to directly link Hg discharges to bioaccumulation due to the existence of multiple industrial Hg sources as well as the varied dietary and migratory...
Janssen, Sarah E.; Patnode, Kathleen A.; Pluta, Bruce R; Krabbenhoft, David P.Attribution: Upper Midwest Water Science Center
Year Published: 2020
Tracing the uptake of Hg(II) in an iron-reducing bacterium using mercury stable isotopes
Anaerobic microorganisms play a key role in the biological mercury (Hg) cycle due to their ability to produce bioaccumulative neurotoxic methylmercury (MeHg). However, despite recent advances, how bacteria accumulate inorganic Hg [Hg(II)] prior to methylation is largely unknown. In this study, we applied Hg stable isotopes to measure changes in...
Wang, Yuwei; Janssen, Sarah E.; Schaefer, Jeffra K; Yee, Nathan; Reinfelder, John RAttribution: Upper Midwest Water Science Center
Year Published: 2020
The assessment and remediation of mercury contaminated sites: A review of current approaches
Remediation of mercury (Hg) contaminated sites has long relied on traditional approaches, such as removal and containment/capping. Here we review contemporary practices in the assessment and remediation of industrial-scale Hg contaminated sites and discuss recent advances. Significant improvements have been made in site assessment, including the...
Eckley, Chris S.; Gilmour, Cynthia C; Janssen, Sarah E.; Luxton, Todd P; Randall, Paul M; Whalin, Lindsay; Carrie AustinAttribution: Upper Midwest Water Science Center
Year Published: 2019
Isolation of methylmercury using distillation and anion-exchange chromatography for isotopic analyses in natural matrices
The development of mercury (Hg) stable isotope measurements has enhanced the study of Hg sources and transformations in the environment. As a result of the mixing of inorganic Hg (iHg) and methylmercury (MeHg) species within organisms of the aquatic food web, understanding species-specific Hg stable isotopic compositions is of significant...
Rosera, Tylor; Janssen, Sarah E.; Tate, Michael T.; Lepak, Ryan F.; Ogorek, Jacob M.; DeWild, John F.; Babiarz, Christopher L.; Krabbenhoft, David P.; Hurley, James P.Attribution: Upper Midwest Water Science Center
Year Published: 2019
Mercury source changes and food web shifts alter contamination signatures of predatory fish from Lake Michigan
To understand the impact reduced mercury (Hg) loading and invasive species have had on methylmercury bioaccumulation in predator fish of Lake Michigan, we reconstructed bioaccumulation trends from a fish archive (1978 to 2012). By measuring fish Hg stable isotope ratios, we related temporal changes in Hg concentrations to varying Hg sources....
Lepak, Ryan F.; Hoffman, Joel C.; Janssen, Sarah E.; Krabbenhoft, David P.; Ogorek, Jacob M.; DeWild, John F.; Tate, Michael T.; Babiarz, Christopher L.; Yin, Runsheng; Murphy, Elizabeth W; Engstrom, Daniel R; Hurley, James P.
Year Published: 2019
Chemical and physical controls on mercury source signatures in stream fish from the northeastern United States
Streams in the northeastern U.S. receive mercury (Hg) in varying proportions from atmospheric deposition and legacy point sources, making it difficult to attribute shifts in fish concentrations directly back to changes in Hg source management. Mercury stable isotope tracers were utilized to relate sources of Hg to co-located fish and bed sediments...
Janssen, Sarah E.; Riva-Murray, Karen; DeWild, John F.; Ogorek, Jacob M.; Tate, Michael T.; Van Metre, Peter C.; Krabbenhoft, David P.; Coles, James F.Attribution: New England Water Science Center, New York Water Science Center, Oklahoma-Texas Water Science Center, Upper Midwest Environmental Sciences Center, Upper Midwest Water Science Center, Water Resources, Toxic Substances Hydrology, Region 6: Arkansas-Rio Grande-Texas-Gulf, Region 4: Mississippi Basin, Region 1: North Atlantic-Appalachian
View Citation
Janssen SE, Riva-Murray K, DeWild JF, Ogorek JM, Tate MT, Van Metre PC, et al. Chemical and Physical Controls on Mercury Source Signatures in Stream Fish from the Northeastern United States. Environmental Science & Technology 2019.
Year Published: 2019
Tracking legacy mercury in the Hackensack River Estuary using mercury stable isotopes
Spatial redistribution of legacy mercury (Hg) contamination in the Hackensack River estuary (New Jersey, USA) was evaluated using mercury stable isotopes. Total Hg varied from 0.06 to 3.8 µg g-1 in sediment from the tidal Hackensack River and from 15 to 154 µg g-1 near historically contaminated sites in upper Berry's Creek, a tributary of the...
Reinfelder, John R; Janssen, Sarah E.Attribution: Upper Midwest Water Science Center, Toxic Substances Hydrology
Year Published: 2019
Rapid pre-concentration of mercury in solids and water for isotopic analysis
The precise quantification of mercury (Hg) stable isotope compositions in low concentration or dilute samples poses analytical challenges due to Hg mass limitations. Common Hg pre-concentration procedures require extended processing times, making rapid Hg stable isotope measurements challenging. Here we present a modified pre-...
Janssen, Sarah E.; Lepak, Ryan F.; Tate, Michael T.; Ogorek, Jacob M.; DeWild, John F.; Babiarz, Christopher L.; Hurley, James P.; Krabbenhoft, David P.Attribution: Upper Midwest Water Science Center, Toxic Substances Hydrology
Year Published: 2019
Mercury isotopes reveal an ontogenetic shift in habitat use by walleye in lower Green Bay of Lake Michigan
In general, fish residing in rivers differ from fish residing in lakes in their mercury (Hg) isotope ratios. Specifically, fish residing in lakes typically show enriched values for the isotope ratios of δ202Hg (mass-dependent fractionation of isotope 202Hg) and Δ199Hg (mass-independent fractionation of isotope 199Hg) compared with fish...
Madenjian, Charles P.; Janssen, Sarah E.; Lepak, Ryan F.; Ogorek, Jacob M.; Rosera, Tylor J.; DeWild, John F.; Krabbenhoft, David P.; Cogswell, Stewart F.; Holey, Mark E.
Year Published: 2018
Factors affecting mercury stable isotopic distribution in piscivorous fish of the Laurentian Great Lakes
Identifying the sources of methylmercury (MeHg) and tracing the transformations of mercury (Hg) in the aquatic food web are important components of effective strategies for managing current and legacy Hg sources. In our previous work, we measured stable isotopes of Hg (δ202Hg, Δ199Hg, and Δ200Hg) in the Laurentian Great Lakes and estimated source...
Janssen, Sarah E.; Yin, Runsheng; Ogorek, Jacob M.; DeWild, John F.; Tate, Michael T.; Holsen, Thomas M.; Hurley, James P.; Lepak, Ryan F.; Janssen, Sarah E.; Yin, Runsheng; Krabbenhoft, David P.; Ogorek, Jacob M.; DeWild, John F.; Tate, Michael T.; Holsen, Thomas M.; Hurley, James P.Attribution: Upper Midwest Water Science Center, Toxic Substances Hydrology
Pre-USGS Publications
Janssen, S.E.; Schaefer, J.K.; Barkay, T.; Reinfelder, J.R. Fractionation of mercury stable isotopes during microbial methylmercury production in pure culture. Environ. Sci. Technol. 2016
Lloyd, N.; Janssen, S.E.; Reinfelder J.R.; Barkay, T., Exposure to mercury selects for antibiotic resistance in Fundulus heteroclitus gut microbiome, Current Microbiology, 2016
Date published: August 20, 2019
Isotopic tracers in fish in Northeast provide clue to mercury sources
Isotopes of mercury in fish can indicate the source of that mercury, reports a new study from the USGS Regional Stream Quality Assessment.
Attribution: Water Resources, National Water Quality Program