Physical Sciences and Mathematics Commons^™

Cysteine Metallochemistry And Metal Binding: Quantification Of The Thermodynamic Foundations Of Cellular Homeostasis, Matthew R. Mehlenbacher

Dartmouth College Ph.D Dissertations

Metals are required for life. Many metalloproteins contain cysteine in their metal-binding site (MBS) and cysteines are unique in that they are reactive, and strongly bind certain metals, which aid in metal selectivity and specificity. Using isothermal titration calorimetry (ITC), the thermodynamic foundation for metal binding, cellular protection, and transcriptional regulation, which all utilize cysteines in their MBS, are quantified.

In bacteria there are metalloprotein pathways that actively uptake mercury, which are regulated by the metalloregulatory protein MerR. MerR de-represses the transcription of these mer proteins in a metal-dependent manner. Using ITC, the thermodynamic foundation of the negative allosteric coupling …

Mercury Contamination In Selected Edible Plants And Soil From Artisanal And Small-Scale Gold Mining In Sukabumi Regency, Indonesia, Grace Serepina Saragih, Ely Rahmi Tapriziah, Yunesfi Syofyan, Siti Masitoh, Yohana Sari Hotmatua Pandiangan, Andriantoro Andriantoro

Makara Journal of Science

Artisanal and small-scale gold mining (ASGM) activities often pollute soil, water, and air, thereby achieving widespread proliferation, and contaminating the surrounding biota including plants. Mercury contamination on agricultural land around ASGM areas has been widely reported. This study aims to determine the total mercury contamination in plants and soil around active ASGM sites in Sukabumi Regency, Indonesia, namely, Waluran, Lengkong, and Ciemas Districts. Total mercury (Hg) content was measured from 27 plant samples (including cassava [Manihot utilisima], rice [Oryza sativa], and papaya [Carica papaya]), 7 rhizosphere soil samples, and 7 non-rhizosphere soil samples. Data …

Association Between Stream Impairment By Mercury And Superfund Sites In The Conterminous Usa, Karessa L. Manning

Masters Theses

Mercury is a natural element that can cause harm to the brain, heart, kidneys, lungs, and immune system, especially to fetuses developing in the womb. Many natural and anthropogenic factors contribute to mercury in the environment, such as geologic deposits, landfills, gold and silver mining operations, cement production, and atmospheric deposition. Mercury has been identified as a contaminant of concern at many National Priority List (NPL) sites, however, studies on contamination at NPL sites are often only conducted on a local level. This study was to analyze the potential connection between mercury-contaminated NPL sites and the presence of mercury impaired …

Evaluation Of An Educational Campaign To Improve The Conscious Consumption Of Recreationally Caught Fish, Corey A. Krabbenhoft, Susan Manente, Donna R. Kashian

Environmental Science and Geology Faculty Research Publications

Consumption guidelines are a common way of improving conscious consumption behaviors in areas where game fish are known to contain contaminants. However, guideline information can be difficult to distribute, and effectiveness difficult to measure. To increase the distribution and effectiveness of guideline information for the Detroit River, an educational campaign was launched in 2010, which included distribution of pamphlets with consumption information, posting of permanent signs at popular fishing locations, and hiring River Walkers to personally communicate with anglers. In 2013 and 2015, we conducted in-person surveys of active shoreline anglers to determine the effectiveness of education and outreach efforts. …

Assessment Of Metals In Tissues Of Marine-Associated Birds In South Florida, Caitlyn A. Nay

HCNSO Student Theses and Dissertations

Seabirds – broadly defined as any bird species associated with the marine environment – are exposed to a wide range of environmental contaminants. Vectors of exposure to metal pollution include by external contact, inhalation, and most often ingestion of food and incidental seawater. Seabirds are often considered marine ecosystem bioindicators due to their high trophic position, relatively long lifespan, and wide geographic ranges. We examined the concentration of total mercury (THg), lead (Pb), and cadmium (Cd), in the kidney, liver, breast muscle, and feathers of seven species of juvenile and adult seabirds commonly found in South Florida: brown pelican Pelecanus …

Mercury Trends In Cormorant And Great Blue Heron Eggs From Pacific Canada: A Question Of Local And Global Sources, Tanya Brown, John E. (John Edward) Elliott, Kyle Elliott, Sandi Lee

Salish Sea Ecosystem Conference

Mercury (Hg) levels and trends in the NE Pacific Ocean are due to the convergence between natural and anthropogenic sources, with the latter broadly related to a combination of local and long-range sources. Legacy and current local point sources include chlor-alkali plants, pulp and paper mills and other mixed sources. In addition, long-range atmospheric and oceanic pathways deliver mercury to the Pacific coast, primarily from points to the west, where it is taken up by algae and bacteria and transferred through the marine food web in its inorganic form, but also its organic form, methylmercury. We present data on Hg …

Spatial Comparison Of Pbts In Marine Fish And Invertebrates From King County Waters, Rory O'Rourke, Jenée Colton, Debra Williston

Salish Sea Ecosystem Conference

In 2014, King County initiated a long-term monitoring program of marine tissue contaminants. The program monitors important prey of marine mammals and species collected for human consumption: Dungeness and Red rock crab, English sole, market squid, and rockfish (brown, copper, and quillback). Sampling locations include Elliott Bay and central Puget Sound sites within King County waters. Generally, PCB concentrations in all species were higher in Elliott Bay compared to other King County locations. With a few exceptions, PBDE concentrations in all species generally exhibited less of a distinct geographical pattern than was observed for PCBs. Contaminant data for Puget Sound …

Persistent Bioaccumulatives In Freshwater Fish Of The Lake Washington Watershed, Jenee Colton, Rory O'Rourke, Richard Jack

Salish Sea Ecosystem Conference

In 2013, King County initiated a long-term monitoring program of freshwater tissue contaminants in three major lakes (Lakes Sammamish, Washington, and Union) and two major rivers (Green and Cedar rivers). Tissue samples are collected from each waterbody every 5 years. Fillet and whole-body fish and invertebrate tissue chemistry data from this program are used to track changes over time associated with management actions, evaluate the risk of adverse effects to aquatic life, and inform human health risk evaluations of fish consumption. The first round of tissue monitoring from all three major lakes was completed in 2017. Species collected spanned a …

Climate Change, One Health And Mercury, L. K. Duffy, T. Vertigan, B. Dainowski, K. Dunlap, Amy Hirons

Marine & Environmental Sciences Faculty Articles

Climate change is occurring on both regional and global scales. The use and global distribution of toxic metals is increasing and affecting environmental, animal and human health as a result of air, water and food contamination. Mercury (Hg) in major forms Hg°, Hg²⁺ and methyl mercury (CH₃Hg⁺) are increasingly available around the globe. Both metal and organic contaminants are impacting the health of all species on the planet. Mercury is an example of a metal that can cause or aggravate a disease state, for example, diabetes. Habitat stewardship is needed to maintain a healthy system, …

An Ecotoxicological Survey Of Tributaries Of The Selenge River, Mongolia, August 2010, Viktor T. Komov, Ch. Javzan, William G. Brumbaugh

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

The biodiversity of the Selenga river basin and the receiving waters of the lake Baikal, are among the greatest in the world with over 1,700 known endemic species of plants and animals. Mining activities along the Selenga river and its tributaries pose a major threat of chemical contamination, potentially reducing habitat quality and suitability for aquatic species. Moreover, the Selenga river serves as a major water source for the lake Baikal. Little information exists on the chemical contaminant concentrations in the Selenga river basin. Thus, the objectives of our study were to evaluate the concentrations of metals in soil, sediment, …

Methylmercury Exposure Via Canned Tuna Fish Consumption And Breast Cancer, Jennifer Bodenrader

Walden Dissertations and Doctoral Studies

Widespread consumption of canned tuna fish since the 1950s may explain some of the increase in breast cancer prevalence in the United States and Europe. Although canned tuna is the primary source of human exposure to methylmercury, its role as an estrogen activating metalloestrogen has been overlooked in the etiology and incidence of breast cancer. Carcinogenic theory asserts that increased exposure to estrogen elevates the risk of breast cancer. The purpose of this population-based, case control study was to examine the association between canned tuna consumption, total blood mercury, and breast cancer in the NHANES 2003-2006 surveys. A multivariable logistic …

Bioaccumulation And Concentration Of Mercury In Rivers And Streams Of The Hudson Bay Lowland, Ashley Warnock

Electronic Thesis and Dissertation Repository

Methylmercury (MeHg) is a neurotoxin that biomagnifies in northern aquatic food webs to high enough concentrations to cause concern for human consumption. The Hudson Bay Lowland of Canada is projected to experience climate and land-use impact in the immediate future, and these environmental stressors may affect the exposure to and subsequent bioaccumulation of MeHg in subarctic fish populations. The focus of this research is to evaluate the spatial variability in total and MeHg in water, sediment, and biota within and across a range of subarctic streams and river reaches of the Hudson Bay Lowland. This data was then used to …

Biogeochemical Analysis Of Ancient Pacific Cod Bone Suggests Hg Bioaccumulation Was Linked To Paleo Sea Level Rise And Climate Change, Maribeth S. Murray, C. Peter Mcroy, L. K. Duffy, Amy Hirons, J. M. Schaaf, Robert P. Trocine, John Trefry

Marine & Environmental Sciences Faculty Articles

Deglaciation at the end of the Pleistocene initiated major changes in ocean circulation and distribution. Within a brief geological time, large areas of land were inundated by sea-level rise and today global sea level is 120 m above its minimum stand during the last glacial maximum. This was the era of modern sea shelf formation; climate change caused coastal plain flooding and created broad continental shelves with innumerable consequences to marine and terrestrial ecosystems and human populations. In Alaska, the Bering Sea nearly doubled in size and stretches of coastline to the south were flooded, with regional variability in the …

Riverine Source Of Arctic Ocean Mercury Inferred From Atmospheric Observations, Jenny A. Fisher, Daniel J. Jacob, Anne L. Soerensen, Helen M. Amos, Alexandra Steffen, Elsie M. Sunderland

Jenny A Fisher

Methylmercury is a potent neurotoxin that accumulates in aquatic food webs. Human activities, including industry and mining, have increased inorganic mercury inputs to terrestrial and aquatic ecosystems. Methylation of this mercury generates methylmercury, and is thus a public health concern. Marine methylmercury is a particular concern in the Arctic, where indigenous peoples rely heavily on marine-based diets. In the summer, atmospheric inorganic mercury concentrations peak in the Arctic, whereas they reach a minimum in the northern mid-latitudes. Here, we use a global three-dimensional ocean–atmosphere model to examine the cause of this Arctic summertime maximum. According to our simulations, circumpolar rivers …

Gas-Particle Partitioning Of Atmospheric Hg(Ii) And Its Effect On Global Mercury Deposition, H M. Amos, D J. Jacob, C D. Holmes, Jenny A. Fisher, Q Wang, R M. Yantosca, E S. Corbitt, E Galarneau, A P. Rutter, M S. Gustin, A Steffen, J J. Schauer, J A. Graydon, V L. St Louis, R W. Talbot, E S. Edgerton, Y Zhang, E N. Sunderland

Jenny A Fisher

Atmospheric deposition represents a major input of mercury to surface environments. The phase of mercury (gas or particle) has important implications for its removal from the atmosphere. We use long-term observations of reactive gaseous mercury (RGM), particle-bound mercury (PBM), fine particulate matter (PM2.5), and temperature at five sites in North America to derive an empirical gas-particle partitioning relationship log10(K-1) = (10 ± 1) − (2500 ± 300)/T where K = (PBM/PM2.5)/RGM with PBM and RGM in common mixing ratio units, PM2.5 in μg m−3, and T in Kelvin. This relationship is in the range of previous work but is based …

Ferritin-Based Photo-Oxidation Of Biomass For Nanoparticle Synthesis, Bioremediation, And Hydrogen Evolution, Oscar Petrucci

Theses and Dissertations

The cell is the basic unit of all living organisms. It is an amazing machine capable of self-replicating, growing, and synthesizing and shuttling thousands of compounds. To perform all of these activities the cell needs energy. The original source of energy for all living beings is the Sun. The energy of the sun is collected by the autotrophs (mostly plants) through photosynthesis and stored in the chemical bonds of carbohydrates and lipids through carboxylic acid intermediates; animals use these compounds to obtain the energy for their cells. Most of the energy extracted by the cell comes from the citric acid …

Recreational Angler Perspectives Of Nonnative Fish Species And Mercury Advisories, Christopher J. Edwards

FIU Electronic Theses and Dissertations

The central Everglades serve as a Wildlife Management Area and as a Water Conservation Area for the Miami-Fort Lauderdale metropolitan area. It is also home to over 22 nonnative freshwater fish species and carries restrictive fish consumption guidelines for Mercury. In my study, boat anglers and canal bank anglers were personally interviewed in the field, to research their awareness and perspectives of these potential environmental and health threats. The study found 78% of anglers were aware of the presence of nonnative fish species, but favored native fish species, and that 69% were aware of mercury advisories, but did not eat …

Gas-Particle Partitioning Of Atmospheric Hg(Ii) And Its Effect On Global Mercury Deposition, H M. Amos, D J. Jacob, C D. Holmes, Jenny A. Fisher, Q Wang, R M. Yantosca, E S. Corbitt, E Galarneau, A P. Rutter, M S. Gustin, A Steffen, J J. Schauer, J A. Graydon, V L. St Louis, R W. Talbot, E S. Edgerton, Y Zhang, E N. Sunderland

Faculty of Science - Papers (Archive)

Atmospheric deposition represents a major input of mercury to surface environments. The phase of mercury (gas or particle) has important implications for its removal from the atmosphere. We use long-term observations of reactive gaseous mercury (RGM), particle-bound mercury (PBM), fine particulate matter (PM_2.5), and temperature at five sites in North America to derive an empirical gas-particle partitioning relationship log₁₀(K^-1) = (10 ± 1) − (2500 ± 300)/T where K = (PBM/PM_2.5)/RGM with PBM and RGM in common mixing ratio units, PM_2.5 in μg m⁻³, and T in …

Riverine Source Of Arctic Ocean Mercury Inferred From Atmospheric Observations, Jenny A. Fisher, Daniel J. Jacob, Anne L. Soerensen, Helen M. Amos, Alexandra Steffen, Elsie M. Sunderland

Faculty of Science - Papers (Archive)

Methylmercury is a potent neurotoxin that accumulates in aquatic food webs. Human activities, including industry and mining, have increased inorganic mercury inputs to terrestrial and aquatic ecosystems. Methylation of this mercury generates methylmercury, and is thus a public health concern. Marine methylmercury is a particular concern in the Arctic, where indigenous peoples rely heavily on marine-based diets. In the summer, atmospheric inorganic mercury concentrations peak in the Arctic, whereas they reach a minimum in the northern mid-latitudes. Here, we use a global three-dimensional ocean–atmosphere model to examine the cause of this Arctic summertime maximum. According to our simulations, circumpolar rivers …

Mercury In The Pelagic And Benthic Food Webs Of The Great Salt Lake, Wayne A. Wurtsbaugh, Erin Fleming, Caleb Izdepski, Jodi Gardberg

Watershed Sciences Faculty Publications

No abstract provided.

Mercury And Selenium Bioaccumulation In The Stromatolite Community Of The Great Salt Lake, Utah, Usa, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

No abstract provided.

Slides: Environmentally Friendly Drilling Systems Program (Efd), Rich Haut

Best Practices for Community and Environmental Protection (October 14)

Presenter: Rich Haut, Houston Advanced Research Center

23 slides

Mercury In The Biostrome Community Of The Great Salt Lake, Wayne A. Wurtsbaugh, Caleb Izdepski

Watershed Sciences Faculty Publications

No abstract provided.

Slides: Paying The Price For Power: When L.A. Turns On The Lights, Northwestern New Mexico Feels It, Jonathan Thompson

Shifting Baselines and New Meridians: Water, Resources, Landscapes, and the Transformation of the American West (Summer Conference, June 4-6)

Presenter: Jonathan Thompson, Editor, High Country News

23 slides

Mercury Concentrations In South Texas Game Fishes, E. Anthony Reisinger

Theses and Dissertations - UTB/UTPA

Mercury (Hg) is one of the most ubiquitous and controversial metals in the world primarily due to the toxicity of the organic form of the metal, methylmercury (MeHg). MeHg is a neurotoxin at high levels, known to manifest its effects on humans primarily through consumption of certain fish and marine mammals, which tend to bioaccumulate MeHg in their tissues over time. Increased fish consumption and, thus, mercury intake in residents of coastal areas necessitates a better awareness of MeHg content in game fish species, thus the subject of this study.

Three hundred thirty-nine tissue samples were taken from 19 south …

Fire And Its Effects On Mercury And Methylmercury Dynamics For Two Watersheds In Acadia National Park, Maine, Kenneth B. Johnson

Electronic Theses and Dissertations

Cross-continental movement of contaminated air masses and prevailing wind direction. Sites covered with softwood vegetation also received higher Hg deposition than other vegetation types because of the higher scavenging efficiency of the canopy structure. MeHg deposition was not affected by these factors. Hg deposition was lower in Cadillac Brook watershed (burned) than in Hadlock Brook watershed (unburned) because regeneration after the fire was dominated by mixed hardwood, whereas softwoods dominate the landscape in Hadlock Brook watershed. The lower deposition could also be a result of the watershed aspect; Cadillac Brook watershed faces southeast to east and Hadlock Brook watershed faces …

Mercury, Copper, And Zinc In Selected Ichthyofauna Of Lower Chesapeake Bay And Hampton Roads, Virginia, W. Bruce Aitenhead

OES Theses and Dissertations

Anchovys, croaker, spat, summer flounder and hogchokers were collected monthly to seasonally from November 1972 to October 1973 at three locations in the southern Chesapeake Bay region of Virginia.

The concentrations of mercury, copper and zinc were determined by atomic absorption spectrophotometry in whole fishes. Metal concentration varied with species and location. Anchovys had the highest mean concentrations of mercury and zinc while hog- chokers had the highest mean copper concentration. Mercury levels exceeding O.5 ppm were observed in species from all three loca- tions, but maximum heavy metal concentrations per species were highest in Craney Island fishes.

Temporal variations …