Filters: Tags: Mercury (X) > partyWithName: Sarah E Janssen (X)
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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, spanning 164 km above the Hells Canyon Complex (Idaho, Oregon). The goal of this study was to identify potential loading sources of methylmercury from the upgradient Snake River into the reservoir complex, with a focus on the tributaries, irrigation return drains, and riparian zones adjacent to agricultural lands along the river....
This data relates to the development of a modified pre-concentration method for mercury (Hg) stable isotope measurements that uses chemical Hg reduction and gold trap amalgamation followed by semi-rapid thermal desorption (less than 1 hour) and chemical trapping in a novel oxidizing solution. The thermal desorption method was demonstrated to perform adequately on multiple trapping matrices previously presented, however our new bromine monochloride (BrCl) wet oxidant trap (40% 3HNO3:BrCl) was deemed superior. As such, this solution was capable of trapping consistently in 2mL volume over a wide range of Hg masses (5 to 200 ng). The procedure was also shown to work effectively on natural matrices, waters and sediments,...
The St Louis River (SLR) is the second largest tributary to Lake Superior and a designated area of concern (AOC) due to past industrial contamination of organic chemicals and heavy metals, including mercury (Hg). Sediments, prey items (odonates, mixed benthic invertebrates, and spiders), and game fish were targeted within this study to determine if industrial sources of Hg were bioaccumulating into the food web. Samples from SLR were directly compared to a reference site in the Bad River, WI to assess if legacy contamination resulted in elevated Hg concentrations in comparisons to background regions with no known point sources. Carbon and nitrogen isotopes were also employed as food web tracers to determine if dietary...
Categories: Data;
Tags: Bad River, WI,
Environmental Health,
Geochemistry,
Lake Superior,
St Louis River, MN,
This dataset includes laboratory analyses of surface water samples and sediment trap material collected from (1) locations upstream, downstream, and within the Hells Canyon Complex (Idaho, Oregon) of the Snake River, (2) tributaries of the Snake River, and (3) two reservoirs near Boise, Idaho, from 2014 to 2022. The study area spans approximately 232 river miles of the Snake River and includes: two sites on the main stem of the Snake River upstream of the Hells Canyon Complex (Snake River mile 447.6, 399.0, and 345.6), six sites within Brownlee Reservoir (Snake River mile 318, 314, 310, 305, 300, and 286), one site within Oxbow Reservoir (Snake River mile 273), two sites within Hells Canyon Reservoir (Snake River...
The Hannibal Pool of the Ohio River is heavily industrialized and receives direct effluent discharges from coal power plants, chlor-alkali plants, and sewage treatment facilities. Mercury (Hg) is a contaminant of concern due to the risk of bioaccumulation at wildlife refuges also located within this region. Mercury concentrations and isotopes compositions were measured to assess the levels and source of Hg contamination, respectively within the system. Sediments and waters were measured to define isotopic end members within Hannibal Pool. Heelsplitter mussels, zebra mussels, and prey fish were also analyzed to determine if Hg source signatures were conserved within the food web. These data are a part of a larger...
Categories: Data;
Tags: Ecology,
Geochemistry,
Hannibal Pool,
Ohio River,
USGS Science Data Catalog (SDC),
The Northeast Stream Quality Assessment (NESQA) performed mercury (Hg) isotope analysis of prey fish, game fish, and sediments from 29 sites across an urban to forested land-use gradient. The data presented here includes the chemical analysis of Hg concentrations and isotopes, capture information for fish species, land use, and stream water quality variables. Using these parameters it was determined that the preservation of Hg isotope signatures, which are indicative of source (e.g. atmospheric deposition, industrial point discharge), were dependent on land use, proximity to point sources, and variables related urbanization (e.g. road density and impervious surface cover). Additional Information regarding the interpretation...
Categories: Data;
Tags: Connecticut,
Massachusetts,
New Hampshire,
New York,
Northeast United States,
As part of the larger Great Lakes Sediment Surveillance Program (GLSSP), the U.S. Geological Survey Mercury Research Laboratory (MRL) partnered with the U.S. Environmental Protection Agency and the University of Minnesota-Duluth to assess contaminant concentrations within surface sediments and sediment cores from the Laurentian Great Lakes. Sediments were assessed for mercury concentrations and mercury stable isotopes to examine spatial trends and sources of mercury within the lakes. In 2021, 30 sites were surveyed in Lake Superior. Mercury concentrations within Lake Superior surface sediment ranged from 1.1 to 161.2 ng/g. Mercury isotopes displayed a range in δ202Hg from -0.12 to -1.74 ‰ with measurable Δ199Hg...
Adult walleye were caught in Fox River (Wisconsin) during April 2014. Age-0 walleye were caught in Fox River during October 2014. Total length, weight, age, and proportion of weight represented by water were determined for each of the walleye. Whole-fish homogenates were prepared during 2014-2015 and during 2017. Total mercury (HgT) concentration, methylmercury (MeHg) concentration, and mercury (Hg) isotope ratios were determined in the homogenates during 2014-2015 and during 2017-2018. All mercury determinations were made at the USGS Mercury Research Laboratory in Middleton, Wisconsin.
Mercury isotope measurements were made across nine sediments cores from remote North American lakes to examine changes in the Hg isotope profiles. The lakes spanned regions of Alaska, Minnesota, and Newfoundland as well as a range of temperate to arctic climates. This data describes the natural record of mass dependent (MDF) and mass independent (MIF) Hg isotope fractionation related to depositional changes over time. Mercury isotope measurements were also compared to factors such as latitude, precipitation, watershed size, and approximate age of sediment intervals. The companion article referencing this data set was published in Environmental Science and Technology and can be found at https://doi.org/10.1021/acs.est.0c00579.
Categories: Data;
Tags: Alaska,
Atmospheric Deposition,
Clever Lake,
Dunnigan Lake,
Environmental Health,
This dataset details mercury concentrations and mercury stable isotope values collected as part of an environmental mercury assessment encompassing the Mobile and Tombigbee Rivers as well as two U.S. Environmental Protection Agency Superfund sites. The Tensaw River was also sampled as part of this study as a reference site, absent of mercury contamination. As a part of this survey, sediments, waters, and biota (largemouth bass) were measured to assess mercury transport and bioaccumulation of mercury within the Mobile River Basin. High mercury concentrations and isotope values indicative of industrial contamination were found in sediments and fish of Superfund sites. Lower concentrations and isotope values indicative...
Note: This data release is currently being revised and is temporarily unavailable. Mercury (Hg) concentrations and isotopic compositions were collected in sediments, soils, and suspended particulate matter from Gruber's Grove Bay (GGB) and upstream reference sites to inform future remedial efforts. The highest concentrations and isotopic signatures (δ202Hg) were observed in soils collected from historic water settling ponds from the Badger Army Ammunition Plant (BAAP). Sediments from the upper portion of GGB showed higher isotopic compositions than sediments from the Wisconsin River. Hg concentrations in sediments were also higher in the upper portion of GGB and decreased towards the river. Sediments collected...
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