Sarah E Janssen
Sarah Janssen is an isotope geochemist working in the M3 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
Education and Certifications
Ph.D. 2016, Environmental Chemistry, Rutgers University, New Brunswick, NJ
B.S. 2011, Chemistry, University of the Sciences, Philadelphia, PA
Science and Products
Filter Total Items: 38
Mercury Stable Isotope Measurements in Water and Suspended Particulate Matter from Snake River Tributaries in Idaho and Oregon, USA Mercury Stable Isotope Measurements in Water and Suspended Particulate Matter from Snake River Tributaries in Idaho and Oregon, USA
This study was designed to examine mercury (Hg) stable isotope values in filtered water and suspended particulate matter from tributaries to the Snake River located in Oregon and Idaho. Water samples were collected from 21 tributary sites representing a range of watershed land use types (e.g., agriculture, forest, etc.) within the Snake River Basin. In 2018, water samples were collected...
Hydrological, Chemical, and Biological Characterization of the Snake River and Associated Tributaries and Irrigation Drains from River Mile 448 to 346, 2022 Hydrological, Chemical, and Biological Characterization of the Snake River and Associated Tributaries and Irrigation Drains from River Mile 448 to 346, 2022
This dataset includes field hydrologic measurements and laboratory analyses of surface and pore waters, sediments, benthic plants/biofilms, and biota along the Middle Snake River upgradient of the Hells Canyon Complex. The study region for this work focuses on a section of the Snake River heavily utilized for agriculture, with complex systems of irrigation diversion and return drainage...
Mercury stable isotopes in biota, sediment, groundwater, and waste piles, Clear Lake area, Lake County, California, 2019-2022 Mercury stable isotopes in biota, sediment, groundwater, and waste piles, Clear Lake area, Lake County, California, 2019-2022
Samples were collected from Clear Lake, California from 2019-2022 by the U.S. Geological Survey (USGS) California Water Science Center, the USGS Forest and Rangeland Ecosystem Science Center (FRESC), the US Environmental Protection Agency, and EA Engineering Science and Technology Inc. to assess the extent and cycling of legacy mercury (Hg) contamination from Sulphur Bank Mine. Samples...
Mercury Stable Isotope Assessment of Global Food Webs Mercury Stable Isotope Assessment of Global Food Webs
This dataset describes mercury (Hg) stable isotope values in fish dorsal muscle from different freshwater environments across the globe. Fish were collected at numerous field sites in North America, South and Central America, Africa, and Asia from 2006-2020. Sub-samples were provided by cooperators to the U.S. Geological Survey Mercury Research Laboratory and the University of Wisconsin...
Assessment of Mercury and Mercury Stable Isotopes in Sediments and Biota from Reservoirs and Remedial Zones within the Saint Louis River, Minnesota Assessment of Mercury and Mercury Stable Isotopes in Sediments and Biota from Reservoirs and Remedial Zones within the Saint Louis River, Minnesota
This data release includes mercury concentrations and mercury stable isotope measurements measured in sediments and biological tissues collected from the Saint Louis River located in Minnesota. Sediments and biota were collected by the U.S. Geological Survey, U.S. Environmental Protection Agency, U.S. Army Corps of Engineers, and federal contractors (Battelle) from 2017-2021. Collection...
Particulate mercury isotope results, fiber optic thermal survey data, and nearshore surface sediment results at the Bremerton Naval Complex, Washington, USA, 2020-21 Particulate mercury isotope results, fiber optic thermal survey data, and nearshore surface sediment results at the Bremerton Naval Complex, Washington, USA, 2020-21
This data release contains four data sets that support ongoing U.S. Geological Survey investigations, in cooperation with the U.S. Navy, at the Bremerton Naval Complex (BNC), Sinclair Inlet, Washington. Child item #1 includes reported concentrations of mercury isotopes in 28 samples of new (2018-19) or archived (2008-09) particulate samples from the BNC, surface sediment from Sinclair...
Chemical characterization of water, sediments, and fish from Water Conservation Areas and Canals of the Florida Everglades (USA), 2012 to 2019 Chemical characterization of water, sediments, and fish from Water Conservation Areas and Canals of the Florida Everglades (USA), 2012 to 2019
This dataset includes field and laboratory measurements of surface waters, pore waters, sediment, and fish from Water Conservation Areas and adjacent canals of the Florida Everglades (USA). Water, sediment, and fish samples were collected from Water Conservation Areas 1 (Arthur R. Marshall Loxahatchee National Wildlife Refuge), 2, and 3 and neighboring canals between 2012 and 2019. The...
African fish mercury burden and isotopic composition from archived museum specimens African fish mercury burden and isotopic composition from archived museum specimens
Fish collected for taxonomic and systematic purposes are often preserved and then archived in museum collections. Preserved fish are commonly first fixed in a formalin solution and then transferred to ethanol for long-term storage. The wet preservation method can potentially introduce mercury (Hg) contamination or unintentionally extract Hg from tissue. An experiment was designed to test...
Mercury Concentrations and Loads in United States and Canadian Tributaries of Lake Superior Mercury Concentrations and Loads in United States and Canadian Tributaries of Lake Superior
In 2021, the U.S. Geological Survey (USGS) Mercury Research Laboratory (MRL) conducted a large-scale assessment of mercury (Hg) concentrations and Hg stable isotope values in tributaries of Lake Superior in order to define the sources and amounts of Hg entering the lake. Water samples were collected monthly from 18 tributaries in the United States from April through October in 2021 and...
Source Identification of Mercury and Methylmercury using Stable Isotope Analysis in the Fox River, WI Source Identification of Mercury and Methylmercury using Stable Isotope Analysis in the Fox River, WI
The lower Fox River in Wisconsin is a heavily industrialized system and the major tributary to Green Bay within Lake Michigan. The region has been a listed as Area of Concern by the United States Environmental Protection Agency (USEPA), indicating severe impairment of the ecological health of the system. Remedial action has taken place along the river to remove extensive polychlorinated...
Assessment of mercury sources in Alaskan lake food webs (version 1.1, September 2023) Assessment of mercury sources in Alaskan lake food webs (version 1.1, September 2023)
This data release includes results of raw water, soil, seston, and fish tissue samples collected from lakes in southwestern Alaska between 2011 and 2016. Specifically, these data include total mercury and methylmercury concentrations in water, size-sieved seston, and particulate matter of 13 remote lakes. Additionally, these data include soil and volcanic ash measurements from the...
Total and Methyl Mercury Water and Fish Concentrations within Everglades National Park Total and Methyl Mercury Water and Fish Concentrations within Everglades National Park
The data in this data release includes results from the analysis of water and fish from 76 sites in the Everglades National Park (ENP). Water and particulate matter samples were collected from 2008 to 2018 and analyzed for total mercury (THg) and methylmercury (MeHg). Filtered water samples were also analyzed for dissolved organic carbon (DOC), specific ultraviolet absorbance (SUVA), and...
Filter Total Items: 50
Riparian methylmercury production increases riverine mercury flux and food web concentrations Riparian methylmercury production increases riverine mercury flux and food web concentrations
The production and uptake of toxic methylmercury (MeHg) impacts aquatic ecosystems globally. Rivers can be dynamic and difficult systems to study for MeHg production and bioaccumulation, hence identifying sources of MeHg to these systems is both challenging and important for resource management within rivers and main-stem reservoirs. Riparian zones, which are known biogeochemical...
Authors
Virginia Krause, Austin K. Baldwin, Benjamin D. Peterson, David P. Krabbenhoft, Sarah E. Janssen, James Willacker, Collin A. Eagles-Smith, Brett A. Poulin
Adaptable plasmonic membrane sensors for fast and reliable detection of trace low micrometer microplastics in lake water Adaptable plasmonic membrane sensors for fast and reliable detection of trace low micrometer microplastics in lake water
In freshwater environments, low-micrometer microplastics (LMMPs) have captured significant attention due to their prevalence and toxicity. Yet, rapid detection of LMMPs (1–10 μm) at the single-particle level within complex freshwater matrices remains a hurdle. We developed an adaptable plasmonic membrane sensor for fast detection of individual LMMPs in eutrophic lake waters. The...
Authors
Ziyan Wu, Sarah E. Janssen, Michael T. Tate, Hoaran Wei, Mohan Qin
Mesopelagic diet as pathway of high mercury levels in body feathers of the endangered Black-capped Petrel (Diablotin) Pterodroma hasitata Mesopelagic diet as pathway of high mercury levels in body feathers of the endangered Black-capped Petrel (Diablotin) Pterodroma hasitata
The Diablotin or Black-capped Petrel Pterodroma hasitata is an endangered gadfly petrel found in the western North Atlantic, Caribbean Sea, and northern Gulf of Mexico. An estimated ~2000 pairs nest at five known sites on Hispaniola, Greater Antilles, although only 120 nests have been located to date. We collected breast feathers and feces from breeding adults in the Dominican Republic...
Authors
Yvan G. Satgé, Sarah E. Janssen, Gemma Clucas, Ernst Rupp, J. Brian Patteson, Patrick G.R. Jodice
Hair mercury isotopes, a noninvasive biomarker for dietary methylmercury exposure and biological uptake Hair mercury isotopes, a noninvasive biomarker for dietary methylmercury exposure and biological uptake
Background. Fish and rice are the main dietary sources of methylmercury (MeHg); however, rice does not contain the same beneficial nutrients as fish, and these differences can impact the observed health effects of MeHg. Hence, it is important to validate a biomarker, which can distinguish among dietary MeHg sources. Methods. Mercury (Hg) stable isotopes were analyzed in hair samples from
Authors
Sarah E Rothenburg, Susan A Korrick, Donald Harrington, Sally W Thurston, Sarah E. Janssen, Michael T. Tate, YanFen Nong, Hua Nong, Jihong Liu, Chuan Hong, Fengxiu Ouyang
Simulated sea level rise in coastal peat oils stimulates mercury methylation Simulated sea level rise in coastal peat oils stimulates mercury methylation
Coastal wetlands are vulnerable to sea level rise with unknown consequences for mercury (Hg) cycling, particularly the potential for exacerbating neurotoxic methylmercury (MeHg) production and bioaccumulation in food webs. Here, the effect of sea level rise on MeHg formation in the Florida Everglades was evaluated by incubating peat cores from a freshwater wetland for 0–20 days in the...
Authors
Bryce A. Cook, Benjamin D. Peterson, Jacob M. Ogorek, Sarah E. Janssen, Brett A. Poulin
Wildfires influence mercury transport, methylation, and bioaccumulation in headwater streams of the Pacific Northwest Wildfires influence mercury transport, methylation, and bioaccumulation in headwater streams of the Pacific Northwest
The increasing frequency and severity of wildfires are among the most visible impacts of climate change. However, the effects of wildfires on mercury (Hg) transformations and bioaccumulation in stream ecosystems are poorly understood. We sampled soils, water, sediment, in-stream leaf litter, periphyton, and aquatic invertebrates in 36 burned (one-year post fire) and 21 reference...
Authors
Austin K. Baldwin, James Willacker, Branden L. Johnson, Sarah E. Janssen, Collin A. Eagles-Smith
Connecting tributary mercury loads to nearshore and offshore sediments in Lake Superior Connecting tributary mercury loads to nearshore and offshore sediments in Lake Superior
Lake Superior has a vast and largely undeveloped watershed in comparison to the other Great Lakes, which makes it challenging to study mercury (Hg) sources and cycling. To examine Hg inputs to Lake Superior, we conducted an expansive binational assessment in 40 watersheds from a diverse range of landcover types. We further paired tributary Hg data to sediment source portfolios in the...
Authors
Sarah E. Janssen, Michael T. Tate, Eric D. Dantoin, Christopher T. Filstrup, Euan D Reavie, Robert M Stewart, Chris Robinson, Craig J Allan, Dale M. Robertson, David P. Krabbenhoft
Geographic drivers of mercury entry into aquatic food webs revealed by mercury stable isotopes in dragonfly larvae Geographic drivers of mercury entry into aquatic food webs revealed by mercury stable isotopes in dragonfly larvae
Atmospheric mercury (Hg) emissions and subsequent transport and deposition are major concerns within protected lands, including national parks, where Hg can bioaccumulate to levels detrimental to human and wildlife health. Despite this risk to biological resources, there is limited understanding of the relative importance of different Hg sources and delivery pathways within protected...
Authors
Sarah E. Janssen, Christopher James Kotalik, James Willacker, Michael T. Tate, Colleen M Flanagan-Pritz, Sarah Nelson, David P. Krabbenhoft, David Walters, Collin A. Eagles-Smith
Integrated science for the study of microplastics in the environment—A strategic science vision for the U.S. Geological Survey Integrated science for the study of microplastics in the environment—A strategic science vision for the U.S. Geological Survey
Executive Summary Evidence of the widespread occurrence of microplastics throughout our environment and exposure to humans and other organisms over the past decade has led to questions about the possibility of health hazards and mitigation of exposures. This document discusses nanoplastics as well as microplastics (referred to solely as microplastics); the microplastics have a range from...
Authors
Deborah D. Iwanowicz, Austin K. Baldwin, Larry B. Barber, Vicki S. Blazer, Steven R. Corsi, Joseph W. Duris, Shawn C. Fisher, Michael Focazio, Sarah E. Janssen, Jeramy Roland Jasmann, Dana W. Kolpin, Johanna M. Kraus, Rachael F. Lane, Mari E. Lee, Kristen B. McSwain, Timothy D. Oden, Timothy J. Reilly, Andrew R. Spanjer
A conceptual site model of contaminant transport pathways from the Bremerton Naval Complex to Sinclair Inlet, Washington, 2011–21 A conceptual site model of contaminant transport pathways from the Bremerton Naval Complex to Sinclair Inlet, Washington, 2011–21
Historical activities on the Bremerton Naval Complex (BNC) in Puget Sound, Washington, have resulted in Sinclair Inlet sediments with elevated concentrations of contaminants, including organic contaminants such as polychlorinated biphenyls and trace elements including mercury. Six U.S. Geological Survey–U.S. Navy datasets have been collected since the last major assessment, in 2013, of...
Authors
Kathleen E. Conn, Sarah E. Janssen, Chad C. Opatz, Valerie A.L. Bright
Competition between dissolved organic matter and freshwater plankton control methylmercury isotope fractionation during uptake and photochemical demethylation Competition between dissolved organic matter and freshwater plankton control methylmercury isotope fractionation during uptake and photochemical demethylation
Isotope fractionation related to photochemical reactions and planktonic uptake at the base of the food web is a major uncertainty in the biological application of mercury (Hg) stable isotopes. In freshwater systems, it is unclear how competitive interactions among methylmercury (MeHg), dissolved organic matter (DOM), and phytoplankton govern the magnitude of mass-dependent and mass...
Authors
Grace Jane Armstrong, Sarah E. Janssen, Brett A. Poulin, Michael T. Tate, David P. Krabbenhoft, James P. Hurley
Mercury sources and budget for the Snake River above a hydroelectric reservoir complex Mercury sources and budget for the Snake River above a hydroelectric reservoir complex
Understanding sources of mercury (Hg) and methylmercury (MeHg) to a water body is critical for management but is often complicated by poorly characterized Hg inputs and in situ processes, such as inorganic Hg methylation. In this study, we determined inorganic Hg and MeHg concentrations and loads (filter-passing and particulate fractions) for a semi-arid 164-kilometer stretch of the...
Authors
Austin K. Baldwin, Sarah E. Janssen, Michael T. Tate, Brett Poulin, Alysa Muir Yoder, Jesse Naymik, Christopher F. Larsen, Charles Hoovestol, David P. Krabbenhoft
Non-USGS Publications**
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
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
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
Filter Total Items: 38
Mercury Stable Isotope Measurements in Water and Suspended Particulate Matter from Snake River Tributaries in Idaho and Oregon, USA Mercury Stable Isotope Measurements in Water and Suspended Particulate Matter from Snake River Tributaries in Idaho and Oregon, USA
This study was designed to examine mercury (Hg) stable isotope values in filtered water and suspended particulate matter from tributaries to the Snake River located in Oregon and Idaho. Water samples were collected from 21 tributary sites representing a range of watershed land use types (e.g., agriculture, forest, etc.) within the Snake River Basin. In 2018, water samples were collected...
Hydrological, Chemical, and Biological Characterization of the Snake River and Associated Tributaries and Irrigation Drains from River Mile 448 to 346, 2022 Hydrological, Chemical, and Biological Characterization of the Snake River and Associated Tributaries and Irrigation Drains from River Mile 448 to 346, 2022
This dataset includes field hydrologic measurements and laboratory analyses of surface and pore waters, sediments, benthic plants/biofilms, and biota along the Middle Snake River upgradient of the Hells Canyon Complex. The study region for this work focuses on a section of the Snake River heavily utilized for agriculture, with complex systems of irrigation diversion and return drainage...
Mercury stable isotopes in biota, sediment, groundwater, and waste piles, Clear Lake area, Lake County, California, 2019-2022 Mercury stable isotopes in biota, sediment, groundwater, and waste piles, Clear Lake area, Lake County, California, 2019-2022
Samples were collected from Clear Lake, California from 2019-2022 by the U.S. Geological Survey (USGS) California Water Science Center, the USGS Forest and Rangeland Ecosystem Science Center (FRESC), the US Environmental Protection Agency, and EA Engineering Science and Technology Inc. to assess the extent and cycling of legacy mercury (Hg) contamination from Sulphur Bank Mine. Samples...
Mercury Stable Isotope Assessment of Global Food Webs Mercury Stable Isotope Assessment of Global Food Webs
This dataset describes mercury (Hg) stable isotope values in fish dorsal muscle from different freshwater environments across the globe. Fish were collected at numerous field sites in North America, South and Central America, Africa, and Asia from 2006-2020. Sub-samples were provided by cooperators to the U.S. Geological Survey Mercury Research Laboratory and the University of Wisconsin...
Assessment of Mercury and Mercury Stable Isotopes in Sediments and Biota from Reservoirs and Remedial Zones within the Saint Louis River, Minnesota Assessment of Mercury and Mercury Stable Isotopes in Sediments and Biota from Reservoirs and Remedial Zones within the Saint Louis River, Minnesota
This data release includes mercury concentrations and mercury stable isotope measurements measured in sediments and biological tissues collected from the Saint Louis River located in Minnesota. Sediments and biota were collected by the U.S. Geological Survey, U.S. Environmental Protection Agency, U.S. Army Corps of Engineers, and federal contractors (Battelle) from 2017-2021. Collection...
Particulate mercury isotope results, fiber optic thermal survey data, and nearshore surface sediment results at the Bremerton Naval Complex, Washington, USA, 2020-21 Particulate mercury isotope results, fiber optic thermal survey data, and nearshore surface sediment results at the Bremerton Naval Complex, Washington, USA, 2020-21
This data release contains four data sets that support ongoing U.S. Geological Survey investigations, in cooperation with the U.S. Navy, at the Bremerton Naval Complex (BNC), Sinclair Inlet, Washington. Child item #1 includes reported concentrations of mercury isotopes in 28 samples of new (2018-19) or archived (2008-09) particulate samples from the BNC, surface sediment from Sinclair...
Chemical characterization of water, sediments, and fish from Water Conservation Areas and Canals of the Florida Everglades (USA), 2012 to 2019 Chemical characterization of water, sediments, and fish from Water Conservation Areas and Canals of the Florida Everglades (USA), 2012 to 2019
This dataset includes field and laboratory measurements of surface waters, pore waters, sediment, and fish from Water Conservation Areas and adjacent canals of the Florida Everglades (USA). Water, sediment, and fish samples were collected from Water Conservation Areas 1 (Arthur R. Marshall Loxahatchee National Wildlife Refuge), 2, and 3 and neighboring canals between 2012 and 2019. The...
African fish mercury burden and isotopic composition from archived museum specimens African fish mercury burden and isotopic composition from archived museum specimens
Fish collected for taxonomic and systematic purposes are often preserved and then archived in museum collections. Preserved fish are commonly first fixed in a formalin solution and then transferred to ethanol for long-term storage. The wet preservation method can potentially introduce mercury (Hg) contamination or unintentionally extract Hg from tissue. An experiment was designed to test...
Mercury Concentrations and Loads in United States and Canadian Tributaries of Lake Superior Mercury Concentrations and Loads in United States and Canadian Tributaries of Lake Superior
In 2021, the U.S. Geological Survey (USGS) Mercury Research Laboratory (MRL) conducted a large-scale assessment of mercury (Hg) concentrations and Hg stable isotope values in tributaries of Lake Superior in order to define the sources and amounts of Hg entering the lake. Water samples were collected monthly from 18 tributaries in the United States from April through October in 2021 and...
Source Identification of Mercury and Methylmercury using Stable Isotope Analysis in the Fox River, WI Source Identification of Mercury and Methylmercury using Stable Isotope Analysis in the Fox River, WI
The lower Fox River in Wisconsin is a heavily industrialized system and the major tributary to Green Bay within Lake Michigan. The region has been a listed as Area of Concern by the United States Environmental Protection Agency (USEPA), indicating severe impairment of the ecological health of the system. Remedial action has taken place along the river to remove extensive polychlorinated...
Assessment of mercury sources in Alaskan lake food webs (version 1.1, September 2023) Assessment of mercury sources in Alaskan lake food webs (version 1.1, September 2023)
This data release includes results of raw water, soil, seston, and fish tissue samples collected from lakes in southwestern Alaska between 2011 and 2016. Specifically, these data include total mercury and methylmercury concentrations in water, size-sieved seston, and particulate matter of 13 remote lakes. Additionally, these data include soil and volcanic ash measurements from the...
Total and Methyl Mercury Water and Fish Concentrations within Everglades National Park Total and Methyl Mercury Water and Fish Concentrations within Everglades National Park
The data in this data release includes results from the analysis of water and fish from 76 sites in the Everglades National Park (ENP). Water and particulate matter samples were collected from 2008 to 2018 and analyzed for total mercury (THg) and methylmercury (MeHg). Filtered water samples were also analyzed for dissolved organic carbon (DOC), specific ultraviolet absorbance (SUVA), and...
Filter Total Items: 50
Riparian methylmercury production increases riverine mercury flux and food web concentrations Riparian methylmercury production increases riverine mercury flux and food web concentrations
The production and uptake of toxic methylmercury (MeHg) impacts aquatic ecosystems globally. Rivers can be dynamic and difficult systems to study for MeHg production and bioaccumulation, hence identifying sources of MeHg to these systems is both challenging and important for resource management within rivers and main-stem reservoirs. Riparian zones, which are known biogeochemical...
Authors
Virginia Krause, Austin K. Baldwin, Benjamin D. Peterson, David P. Krabbenhoft, Sarah E. Janssen, James Willacker, Collin A. Eagles-Smith, Brett A. Poulin
Adaptable plasmonic membrane sensors for fast and reliable detection of trace low micrometer microplastics in lake water Adaptable plasmonic membrane sensors for fast and reliable detection of trace low micrometer microplastics in lake water
In freshwater environments, low-micrometer microplastics (LMMPs) have captured significant attention due to their prevalence and toxicity. Yet, rapid detection of LMMPs (1–10 μm) at the single-particle level within complex freshwater matrices remains a hurdle. We developed an adaptable plasmonic membrane sensor for fast detection of individual LMMPs in eutrophic lake waters. The...
Authors
Ziyan Wu, Sarah E. Janssen, Michael T. Tate, Hoaran Wei, Mohan Qin
Mesopelagic diet as pathway of high mercury levels in body feathers of the endangered Black-capped Petrel (Diablotin) Pterodroma hasitata Mesopelagic diet as pathway of high mercury levels in body feathers of the endangered Black-capped Petrel (Diablotin) Pterodroma hasitata
The Diablotin or Black-capped Petrel Pterodroma hasitata is an endangered gadfly petrel found in the western North Atlantic, Caribbean Sea, and northern Gulf of Mexico. An estimated ~2000 pairs nest at five known sites on Hispaniola, Greater Antilles, although only 120 nests have been located to date. We collected breast feathers and feces from breeding adults in the Dominican Republic...
Authors
Yvan G. Satgé, Sarah E. Janssen, Gemma Clucas, Ernst Rupp, J. Brian Patteson, Patrick G.R. Jodice
Hair mercury isotopes, a noninvasive biomarker for dietary methylmercury exposure and biological uptake Hair mercury isotopes, a noninvasive biomarker for dietary methylmercury exposure and biological uptake
Background. Fish and rice are the main dietary sources of methylmercury (MeHg); however, rice does not contain the same beneficial nutrients as fish, and these differences can impact the observed health effects of MeHg. Hence, it is important to validate a biomarker, which can distinguish among dietary MeHg sources. Methods. Mercury (Hg) stable isotopes were analyzed in hair samples from
Authors
Sarah E Rothenburg, Susan A Korrick, Donald Harrington, Sally W Thurston, Sarah E. Janssen, Michael T. Tate, YanFen Nong, Hua Nong, Jihong Liu, Chuan Hong, Fengxiu Ouyang
Simulated sea level rise in coastal peat oils stimulates mercury methylation Simulated sea level rise in coastal peat oils stimulates mercury methylation
Coastal wetlands are vulnerable to sea level rise with unknown consequences for mercury (Hg) cycling, particularly the potential for exacerbating neurotoxic methylmercury (MeHg) production and bioaccumulation in food webs. Here, the effect of sea level rise on MeHg formation in the Florida Everglades was evaluated by incubating peat cores from a freshwater wetland for 0–20 days in the...
Authors
Bryce A. Cook, Benjamin D. Peterson, Jacob M. Ogorek, Sarah E. Janssen, Brett A. Poulin
Wildfires influence mercury transport, methylation, and bioaccumulation in headwater streams of the Pacific Northwest Wildfires influence mercury transport, methylation, and bioaccumulation in headwater streams of the Pacific Northwest
The increasing frequency and severity of wildfires are among the most visible impacts of climate change. However, the effects of wildfires on mercury (Hg) transformations and bioaccumulation in stream ecosystems are poorly understood. We sampled soils, water, sediment, in-stream leaf litter, periphyton, and aquatic invertebrates in 36 burned (one-year post fire) and 21 reference...
Authors
Austin K. Baldwin, James Willacker, Branden L. Johnson, Sarah E. Janssen, Collin A. Eagles-Smith
Connecting tributary mercury loads to nearshore and offshore sediments in Lake Superior Connecting tributary mercury loads to nearshore and offshore sediments in Lake Superior
Lake Superior has a vast and largely undeveloped watershed in comparison to the other Great Lakes, which makes it challenging to study mercury (Hg) sources and cycling. To examine Hg inputs to Lake Superior, we conducted an expansive binational assessment in 40 watersheds from a diverse range of landcover types. We further paired tributary Hg data to sediment source portfolios in the...
Authors
Sarah E. Janssen, Michael T. Tate, Eric D. Dantoin, Christopher T. Filstrup, Euan D Reavie, Robert M Stewart, Chris Robinson, Craig J Allan, Dale M. Robertson, David P. Krabbenhoft
Geographic drivers of mercury entry into aquatic food webs revealed by mercury stable isotopes in dragonfly larvae Geographic drivers of mercury entry into aquatic food webs revealed by mercury stable isotopes in dragonfly larvae
Atmospheric mercury (Hg) emissions and subsequent transport and deposition are major concerns within protected lands, including national parks, where Hg can bioaccumulate to levels detrimental to human and wildlife health. Despite this risk to biological resources, there is limited understanding of the relative importance of different Hg sources and delivery pathways within protected...
Authors
Sarah E. Janssen, Christopher James Kotalik, James Willacker, Michael T. Tate, Colleen M Flanagan-Pritz, Sarah Nelson, David P. Krabbenhoft, David Walters, Collin A. Eagles-Smith
Integrated science for the study of microplastics in the environment—A strategic science vision for the U.S. Geological Survey Integrated science for the study of microplastics in the environment—A strategic science vision for the U.S. Geological Survey
Executive Summary Evidence of the widespread occurrence of microplastics throughout our environment and exposure to humans and other organisms over the past decade has led to questions about the possibility of health hazards and mitigation of exposures. This document discusses nanoplastics as well as microplastics (referred to solely as microplastics); the microplastics have a range from...
Authors
Deborah D. Iwanowicz, Austin K. Baldwin, Larry B. Barber, Vicki S. Blazer, Steven R. Corsi, Joseph W. Duris, Shawn C. Fisher, Michael Focazio, Sarah E. Janssen, Jeramy Roland Jasmann, Dana W. Kolpin, Johanna M. Kraus, Rachael F. Lane, Mari E. Lee, Kristen B. McSwain, Timothy D. Oden, Timothy J. Reilly, Andrew R. Spanjer
A conceptual site model of contaminant transport pathways from the Bremerton Naval Complex to Sinclair Inlet, Washington, 2011–21 A conceptual site model of contaminant transport pathways from the Bremerton Naval Complex to Sinclair Inlet, Washington, 2011–21
Historical activities on the Bremerton Naval Complex (BNC) in Puget Sound, Washington, have resulted in Sinclair Inlet sediments with elevated concentrations of contaminants, including organic contaminants such as polychlorinated biphenyls and trace elements including mercury. Six U.S. Geological Survey–U.S. Navy datasets have been collected since the last major assessment, in 2013, of...
Authors
Kathleen E. Conn, Sarah E. Janssen, Chad C. Opatz, Valerie A.L. Bright
Competition between dissolved organic matter and freshwater plankton control methylmercury isotope fractionation during uptake and photochemical demethylation Competition between dissolved organic matter and freshwater plankton control methylmercury isotope fractionation during uptake and photochemical demethylation
Isotope fractionation related to photochemical reactions and planktonic uptake at the base of the food web is a major uncertainty in the biological application of mercury (Hg) stable isotopes. In freshwater systems, it is unclear how competitive interactions among methylmercury (MeHg), dissolved organic matter (DOM), and phytoplankton govern the magnitude of mass-dependent and mass...
Authors
Grace Jane Armstrong, Sarah E. Janssen, Brett A. Poulin, Michael T. Tate, David P. Krabbenhoft, James P. Hurley
Mercury sources and budget for the Snake River above a hydroelectric reservoir complex Mercury sources and budget for the Snake River above a hydroelectric reservoir complex
Understanding sources of mercury (Hg) and methylmercury (MeHg) to a water body is critical for management but is often complicated by poorly characterized Hg inputs and in situ processes, such as inorganic Hg methylation. In this study, we determined inorganic Hg and MeHg concentrations and loads (filter-passing and particulate fractions) for a semi-arid 164-kilometer stretch of the...
Authors
Austin K. Baldwin, Sarah E. Janssen, Michael T. Tate, Brett Poulin, Alysa Muir Yoder, Jesse Naymik, Christopher F. Larsen, Charles Hoovestol, David P. Krabbenhoft
Non-USGS Publications**
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
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
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