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Full-Text Articles in Life Sciences

Comment On Faa Rule Revision - Transport Category Aircraft, Paul F. Eschenfelder, Valter Battistoni Nov 2015

Comment On Faa Rule Revision - Transport Category Aircraft, Paul F. Eschenfelder, Valter Battistoni

Paul F. Eschenfelder

No abstract provided.


Toxicodynamic Modeling Of 137cs To Estimate White-Tailed Deer Background Levels For The Department Of Energy's Savannah River Site, Karen F. Gaines, James M. Novak, Christopher W. Bobryk, Susan A. Blas Jan 2014

Toxicodynamic Modeling Of 137cs To Estimate White-Tailed Deer Background Levels For The Department Of Energy's Savannah River Site, Karen F. Gaines, James M. Novak, Christopher W. Bobryk, Susan A. Blas

Karen F. Gaines

The U.S. Department of Energy's (USDOE) Savannah River Site (SRS) is a former nuclear weapon material production and current research facility adjacent to the Savannah River in South Carolina, USA. The purpose of this study was to determine the background radiocesium (137Cs) body burden (e.g., from global fallout) for white-tailed deer (Odocoileus virginianus) inhabiting the SRS. To differentiate what the background burden is for the SRS versus 137Cs obtained from SRS nuclear activities, data were analyzed spatially, temporally and compared to other off-site hunting areas near the SRS. The specific objectives of this study were: to compare ...


New Peril + Old Promises = Bad Results, Paul Eschenfelder Feb 2013

New Peril + Old Promises = Bad Results, Paul Eschenfelder

Paul F. Eschenfelder

No abstract provided.


Erau Spring 2013 Newsletter, Paul Eschenfelder Jan 2013

Erau Spring 2013 Newsletter, Paul Eschenfelder

Paul F. Eschenfelder

No abstract provided.


A Spatially Explicit Model To Predict Radiocesium Body Burdens Of White- Tailed Deer On The U.S. Department Of Energy's Savannah River Site, Christopher W. Bobryk, Karen F. Gaines, James M. Novak, Susan A. Blas Jan 2013

A Spatially Explicit Model To Predict Radiocesium Body Burdens Of White- Tailed Deer On The U.S. Department Of Energy's Savannah River Site, Christopher W. Bobryk, Karen F. Gaines, James M. Novak, Susan A. Blas

Karen F. Gaines

We developed a spatially explicit exposure model to interpolate and predict radiocesium (137Cs) body burdens found in white-tailed deer (Odocoileus virginianus) on the U.S. Department of Energy’s (USDOE) Savannah River Site (SRS) to gain insight into and differentiate between the main contributing sources of this radionuclide for use in harvest management strategies that focus on minimizing human risk. Hunting has been allowed from permanent stands as a mechanism to manage the deer herd since 1965. All animals are monitored in the field for gross beta and gamma activity levels, providing a spatially explicit dataset. The models described here ...


Assessing Multiple Endpoints Of Atrazine Ingestion On Gravid Northern Watersnakes (Nerodia Sipedon) And Their Offspring, Lorin A. Neuman-Lee, Karen F. Gaines, Kyle A. Baumgartner, Jayme R. Voorhees, James M. Novak, Stephen J. Mullin Jan 2013

Assessing Multiple Endpoints Of Atrazine Ingestion On Gravid Northern Watersnakes (Nerodia Sipedon) And Their Offspring, Lorin A. Neuman-Lee, Karen F. Gaines, Kyle A. Baumgartner, Jayme R. Voorhees, James M. Novak, Stephen J. Mullin

Karen F. Gaines

Ecotoxicological studies that focus on a single endpoint might not accurately and completely represent the true ecological effects of a contaminant. Exposure to atrazine, a widely used herbicide, disrupts endocrine function and sexual development in amphibians, but studies involving live-bearing reptiles are lacking. This study tracks several effects of atrazine ingestion from female Northern Watersnakes (Nerodia sipedon) to their offspring exposed in utero. Twenty-five gravid N. sipedon were fed fish dosed with one of the four levels of atrazine (0, 2, 20, or 200 ppb) twice weekly for the entirety of their gestation period. Endpoints for the mothers included blood ...


Erau Aviation Wildlife Hazard Newsletter, Paul Eschenfelder Jan 2011

Erau Aviation Wildlife Hazard Newsletter, Paul Eschenfelder

Paul F. Eschenfelder

No abstract provided.


Is The Lcp Superfund Site An Ecological Trap For Clapper Rails?, Karen F. Gaines, Jay W. Summers, James C. Cumbee Jr., Warren L. Stephens Jr., Gary L. Mills Jan 2011

Is The Lcp Superfund Site An Ecological Trap For Clapper Rails?, Karen F. Gaines, Jay W. Summers, James C. Cumbee Jr., Warren L. Stephens Jr., Gary L. Mills

Karen F. Gaines

Rallus longirostris (Clapper Rail) is considered a good indicator species for toxicants because of its strong site fidelity and predictable diet of benthic organisms. High levels of the rare PCB Aroclor 1268 have been found in Clapper Rail adults, chicks, and eggs from the marshes associated with the Linden Chemical Plant (LCP) in Brunswick, GA. Recently, sampling and testing feathers has successfully been used as a non-lethal tool to trace exposure and assimilation of Aroclor 1268 in rails from the LCP site. This approach allows us to infer how and when these birds are exposed to contaminants in the marsh ...


Birdstrike Mitigation - Beyond The Airport, Paul Eschenfelder, Russ Defusco Aug 2010

Birdstrike Mitigation - Beyond The Airport, Paul Eschenfelder, Russ Defusco

Paul F. Eschenfelder

No abstract provided.


Feathers As Bioindicators Of Pcb Exposure In Clapper Rails, Jay W. Summers, Karen F. Gaines, N. Garvin, Warren L. Stephens Jr., James C. Cumbee Jr., Gary L. Mills Jan 2010

Feathers As Bioindicators Of Pcb Exposure In Clapper Rails, Jay W. Summers, Karen F. Gaines, N. Garvin, Warren L. Stephens Jr., James C. Cumbee Jr., Gary L. Mills

Karen F. Gaines

In this study we used feathers to biomonitor exposure to the polychlorinated biphenyl (PCB) Aroclor 1268 congener mixture in clapper rails (Rallus longirostris). This species has been used as an indicator species of environmental damage for the LCP superfund site located in Brunswick, GA, USA which is contaminated with Aroclor 1268, a congener mixture that has been used in limited amounts elsewhere and therefore can be used as a contaminant marker. The Aroclor 1268 congener mixture, including congener profiles, were quantified in feathers using gas chromatography (GC). Concurrently, each sample was quantified for the total Aroclor 1268 congener mixture using ...


Responses Of Bats To Forest Fragmentation In The Mississippi River Alluvial Valley, Arkansas, Usa, Rex E. Medlin Jr., Matthew B. Connior, Karen F. Gaines, Thomas S. Risch Jan 2010

Responses Of Bats To Forest Fragmentation In The Mississippi River Alluvial Valley, Arkansas, Usa, Rex E. Medlin Jr., Matthew B. Connior, Karen F. Gaines, Thomas S. Risch

Karen F. Gaines

Intense conversion of bottomland hardwood forests to rice and soybeans in the Mississippi River Valley of Arkansas has restricted the remaining forest to isolated fragments. Habitat fragmentation has proven to be detrimental to population sustainability of several species, and is the subject of intense study with often species and latitude specific responses. We compared both coarse land area classes and landscape fragmentation metrics from six 30 km × 30 km subsets centered on publicly owned management areas to bat captures obtained from a 2005 population study. Patch density was the strongest predictor of total captures (R 2 = 0.801, p = 0 ...


Tissue-Diet Discrimination Factors And Turnover Of Stable Carbon And Nitrogen Isotopes In White-Footed Mice (Peromyscus Leucopus), Rachel L. Demots, James M. Novak, Karen F. Gaines, Aaron J. Gregor, Christopher S. Romanek, Daniel A. Soluk Jan 2010

Tissue-Diet Discrimination Factors And Turnover Of Stable Carbon And Nitrogen Isotopes In White-Footed Mice (Peromyscus Leucopus), Rachel L. Demots, James M. Novak, Karen F. Gaines, Aaron J. Gregor, Christopher S. Romanek, Daniel A. Soluk

Karen F. Gaines

Stable isotope analysis has become an increasingly valuable tool in investigating animal ecology. Here we document the turnover rates for carbon in the liver, muscle, and whole blood tissue, as well as the tissue-diet discrimination values for carbon and nitrogen isotopes in the liver, whole blood, muscle, and hair, of the white-footed mouse (Peromyscus leucopus (Rafinesque, 1818)). A 168-day diet-switching experiment was conducted with a laboratory population of white-footed mice. The δ13C values for all tissues deviated less than 1‰ from those of the diet except for whole blood, which had a slightly higher tissue-diet discrimination factor of 1.8 ...


Dna Double-Strand Breakage As An Endpoint To Examine Metal And Radionuclide Exposure Effects To Water Snakes On A Nuclear Industrial Site, Stephanie M. Murray, Karen F. Gaines, James M. Novak, Michael Gochfeld, Joanna Burger Jan 2010

Dna Double-Strand Breakage As An Endpoint To Examine Metal And Radionuclide Exposure Effects To Water Snakes On A Nuclear Industrial Site, Stephanie M. Murray, Karen F. Gaines, James M. Novak, Michael Gochfeld, Joanna Burger

Karen F. Gaines

This study examined metal levels (especially U and Ni) in the tail tissues of water snakes from contaminated (Tim’s Branch) and reference areas on the Department of Energy’s Savannah River Site (SRS). Home ranges of snakes were quantified to determine the ratio of the habitat that they use in relation to the contaminated areas to better estimate exposure Compared to conventional methods that do not. The exposure assessment indicated that water snakes in the contaminated areas could expect U exposure at 3–4 orders of magnitude greater than the Agency for Toxic Substances and Disease Registry’sMinimum Risk ...


Raccoon (Procyon Lotor) Harvesting On And Near The U.S. Department Of Energy’S Savannah River Site, Karen F. Gaines, James M. Novak Jan 2008

Raccoon (Procyon Lotor) Harvesting On And Near The U.S. Department Of Energy’S Savannah River Site, Karen F. Gaines, James M. Novak

Karen F. Gaines

Understanding the toxicodynamics of wildlife populations in contaminated ecosystems is one of the greatest challenges in ecotoxicology today. The goal is to manage these populations to minimize risk to ecosystem integrity as well as human health. Ecological risk assessments (ERAs) in the United States are designed to meet the regulatory mandates of the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) and the Resource Conservation and Recovery Act. According to the U.S. Environmental Protection Agency, an ERA evaluates the potential adverse effects that human activities have on the ' ora and fauna that de( ne an ecosystem (U.S. Environmental ...


Exposure And Exposure Modeling, Karen F. Gaines, T. E. Chow, S. A. Dyer Jan 2008

Exposure And Exposure Modeling, Karen F. Gaines, T. E. Chow, S. A. Dyer

Karen F. Gaines

Exposure to contaminants in the environment is quantified through the ecological risk assessment (ERA) process which provides a framework for the development and implementation of environmental management decisions. The ERA uses available toxicological and ecological information to estimate the probability of occurrence for a specified undesired ecological event or endpoint. The level for these endpoints depends on the objectives and the constraints imposed upon the risk assessment process; therefore, multiple endpoints at different scales may be necessary. ERAs Ecotoxicology | Exposure and Exposure Assessment 1527Author's personal copy often rely on the link between these undesired endpoints to a threshold of ...


Clapper Rails As Indicators Of Mercury And Pcb Bioavailability In A Georgia Saltmarsh System, James C. Cumbee Jr., Karen F. Gaines, Gary L. Mills, N. Garvin, Warren L. Stephens Jr., James N. Novak, I. L. Brisbin Jr. Jan 2008

Clapper Rails As Indicators Of Mercury And Pcb Bioavailability In A Georgia Saltmarsh System, James C. Cumbee Jr., Karen F. Gaines, Gary L. Mills, N. Garvin, Warren L. Stephens Jr., James N. Novak, I. L. Brisbin Jr.

Karen F. Gaines

Clapper rails (Rallus longirostris) were used as an indicator species of estuarine marsh habitat quality because of their strong site fidelity and predictable diet consisting of mostly benthic organisms. Mercury (Hg) and the polychlorinated biphenyl (PCB) Aroclor 1268 concentrations were determined for sediments, crabs, as well as clapper rail adults and chicks collected from salt marshes associated with the LCP Superfund site in Brunswick, Georgia. Home ranges were established for adult rails, and sediment and crab samples were taken from each individual’s range. The study was designed to minimize the spatial variability associated with trophic transfer studies by choosing ...


The Clapper Rail As An Indicator Species Of Estuarine Marsh Health, James N. Novak, Karen F. Gaines, James C. Cumbee Jr., Gary L. Mills, Alejandro Rodriguez-Navarro, Christopher S. Romanek Jan 2006

The Clapper Rail As An Indicator Species Of Estuarine Marsh Health, James N. Novak, Karen F. Gaines, James C. Cumbee Jr., Gary L. Mills, Alejandro Rodriguez-Navarro, Christopher S. Romanek

Karen F. Gaines

Clapper Rails (Rallus longirostris) can potentially serve as an indicator species of estuarinemarsh health because of their strong site fi delity and predictable diet consisting predominantly of benthic organisms. These feeding habits increase the likelihood of individuals accumulating signifi - cant amounts of contaminants associated with coastal sediments. Moreover, since Clapper Rails are threatened in most of their western range, additional study of the effects of potential toxins on these birds is essential to conservation programs for this species. Here we present techniques (DNA strand breakage, eggshell structure, and human-consumption risk) that can be used to quantify detrimental effects to Clapper ...


Effect Of In Ovo Exposure To Pcbs And Hg On Clapper Rail Bone Mineral Chemistry From A Contaminated Salt Marsh In Coastal Georgia, Alejandro Rodriquez-Navarro, Christopher S. Romanek, Pedro Alvarez-Lloret, Karen F. Gaines Jan 2006

Effect Of In Ovo Exposure To Pcbs And Hg On Clapper Rail Bone Mineral Chemistry From A Contaminated Salt Marsh In Coastal Georgia, Alejandro Rodriquez-Navarro, Christopher S. Romanek, Pedro Alvarez-Lloret, Karen F. Gaines

Karen F. Gaines

The effect of Hg and PCBs (Aroclor 1268) on bone characteristics was investigated in a population of Clapper Rails (Rallus longirostris) inhabiting contaminated and unimpacted estuarine marsh systems in coastal Georgia. Exposure to contaminants did not affect the length or weight of leg bones, but it significantly altered the chemical composition of the bone. Specifically, bone in the contaminated site had a higher Ca to P, and lower carbonate and acid phosphate content. These characteristics are typical of more mature bone mineral and indicate that toxicants have accelerated bone maturation. FTIR spectroscopy data revealed a dose dependent change in the ...


The Development Of A Spatially Explicit Model To Estimate, Karen F. Gaines, C. Shane Boring, Dwayne E. Porter Jan 2005

The Development Of A Spatially Explicit Model To Estimate, Karen F. Gaines, C. Shane Boring, Dwayne E. Porter

Karen F. Gaines

A spatially explicit model of raccoon (Procyon lotor) distribution for the U.S. Department of Energy’s (DOE) Savannah River Site (SRS) in west-central South Carolina was developed using data from a raccoon radio-telemetry study and visualized within a Geographic Information System (GIS). An inductive approach was employed to develop three sub-models using the ecological requirements of raccoons studied in the following habitats: (1) man-made reservoirs, (2) bottomland hardwood/ riverine systems, and (3) isolated wetland systems. Logistic regression was used to derive probabilistic resource selection functions using habitat compositional data and landscape metrics. The final distribution model provides a spatially ...


Rodents As Receptor Species At A Tritium, Angel Kelsey-Wall, John C. Seaman, Charles H. Jegoe, Cham E. Dallas, Karen F. Gaines Jan 2005

Rodents As Receptor Species At A Tritium, Angel Kelsey-Wall, John C. Seaman, Charles H. Jegoe, Cham E. Dallas, Karen F. Gaines

Karen F. Gaines

New methods are being employed on the Department of Energy’s Savannah River Site to deal with the disposal of tritium, including the irrigation of a hardwood/pine forest with tritiated water from an intercepted contaminant plume to reduce concentrations of tritium outcropping into Fourmile Branch, a tributary of the Savannah River. The use of this system has proven to be an effective means of tritium disposal. To evaluate the impact of this activity on terrestrial biota, rodent species were captured on the tritium disposal site and a control site during two trapping seasons in order to assess tritium exposure ...


A Spatially Explicit Model Of The Wild Hog For Ecological Risk Assessment Activities At The Department Of Energy's Savannah River Site, Karen F. Gaines, Dwayne E. Porter, Tracy Punshon, I. Lehr Brisbin Jr. Jan 2005

A Spatially Explicit Model Of The Wild Hog For Ecological Risk Assessment Activities At The Department Of Energy's Savannah River Site, Karen F. Gaines, Dwayne E. Porter, Tracy Punshon, I. Lehr Brisbin Jr.

Karen F. Gaines

In North America, wild hogs (Sus scrofa) are both sought after as prime game and despised due to their detrimental impacts to the environment from their digging and rooting behavior. They are also a potentially useful indicator species for environmental health for both ecological- and human-based risk assessments. An inductive approach was used to develop probabilistic resource selection models using logistic regression to quantify the likelihood of hogs being in any area of the Department of Energy’s 805 km2 Savannah River Site (SRS) in west-central South Carolina. These models were derived by using available SRS hog hunt data from ...


Habitat And Exposure Modelling For Ecological Risk Assessment: A, T. Edwin Chow, Karen F. Gaines, Michael E. Hodgson, Machelle D. Wilson Jan 2005

Habitat And Exposure Modelling For Ecological Risk Assessment: A, T. Edwin Chow, Karen F. Gaines, Michael E. Hodgson, Machelle D. Wilson

Karen F. Gaines

Contamination has a dramatic impact on the health of ecosystem and habitat suitability for the inhabited flora and fauna. The Environmental Protection Agency (EPA) mandates an ecological risk assessment (ERA) that evaluates the potential adverse impact of any anthropogenic activities on the ecosystem (US Environmental Protection Agency, 1997. Ecological Risk Assessment Guidance for Superfund: Process for Designing and Conducting Ecological Risk Assessment. EPA/630/R-021011, Washington, DC). This study provides a general framework and specific procedures to predict the contaminant exposure of midsized mammals using a geographical information system (GIS)-based Monte Carlo simulation model. The model was applied to ...


Using Wildlife As Receptor Species: A Landscape, Karen F. Gaines, Dwayne E. Porter, Susan A. Dyer, Gary R. Wein, John E. Pinder Iii, I. Lehr Brisbin Jr. Jan 2004

Using Wildlife As Receptor Species: A Landscape, Karen F. Gaines, Dwayne E. Porter, Susan A. Dyer, Gary R. Wein, John E. Pinder Iii, I. Lehr Brisbin Jr.

Karen F. Gaines

To assist risk assessors at the Department of Energy’s Savannah River Site (SRS), a Geographic Information System (GIS) application was developed to provide relevant information about specific receptor species of resident wildlife that can be used for ecological risk assessment. Information was obtained from an extensive literature review of publications and reports on vertebrate- and contaminant- related research since 1954 and linked to a GIS. Although this GIS is a useful tool for risk assessors because the data quality is high, it does not describe the species’ site-wide spatial distribution or life history, which may be crucial when developing ...


Effects Of Cooking On Radiocesium In Fish From The Savannah River: Exposure Differences For The Public, Joanna Burger, Karen F. Gaines, C. Shane Boring, J. Snodgrass, W. L. Stephens Jr., M. Gochfeld Jan 2004

Effects Of Cooking On Radiocesium In Fish From The Savannah River: Exposure Differences For The Public, Joanna Burger, Karen F. Gaines, C. Shane Boring, J. Snodgrass, W. L. Stephens Jr., M. Gochfeld

Karen F. Gaines

Understanding the factors that contribute to the risk from fish consumption is an important public health concern because of potential adverse effects of radionuclides, organochlorines, other pesticides, and mercury. Risk from consumption is normally computed on the basis of contaminant levels in fish, meal frequency, and meal size, yet cooking practices may also affect risk. This study examines the effect of deep-frying on radiocesium (137Cs) levels and risk to people fishing along the Savannah River. South Carolina and Georgia have issued consumption advisories for the Savannah River, based partly on 137Cs. 137Cs levels were significantly higher in the cooked fish ...


Nest Characteristics Of The Clapper Rail In Coastal Georgia, Karen F. Gaines, James C. Cumbee Jr., Warren L. Stephens Jr. Jan 2003

Nest Characteristics Of The Clapper Rail In Coastal Georgia, Karen F. Gaines, James C. Cumbee Jr., Warren L. Stephens Jr.

Karen F. Gaines

The nesting habitat of the Clapper Rail (Rallus longirostris) is not well studied in the southeastern United States. We documented Clapper Rail nest characteristics and surrounding habitats near Brunswick on the Georgia coast. Of 159 nests found, only 29 were active. Although some nests may have been abandoned or never used, many could have been depredated. Nests were constructed farther away from tidal influences than in those populations studied in the mid-Atlantic region of the United States. Clapper Rails also tended to nest near tidal pools as frequently as tidal creeks, contrasting with other Atlantic coast studies. The greater tidal ...


Bioavailability Of Uranium And Nickel To Vegetation In A Contaminated Riparian Ecosystem, Tracy Punshon, Karen F. Gaines, Paul M. Bertsch, Joanna Burger Jan 2003

Bioavailability Of Uranium And Nickel To Vegetation In A Contaminated Riparian Ecosystem, Tracy Punshon, Karen F. Gaines, Paul M. Bertsch, Joanna Burger

Karen F. Gaines

The lower portion of Tims Branch (TB), a second-order stream system on the Savannah River site (SC, USA), receives influx of mixed waste-contaminated sediments from Steed Pond, a former settling basin for target processing wastes for over three decades. The magnitude and distribution of U, Ni, and other metals and the potential for trophic movement were studied to facilitate risk assessment and determine potential remedial action. Total and sequential extraction of TB soils demonstrated contaminant heterogeneity both spatially and between operationally defined fractions. Metal concentrations were elevated within riparian zone soils in contrast to stream sediments, suggesting off-site transport. Leaf ...


Coastal Habitat Use By Wood Storks During The Non-Breeding Season, A. L. Bryan Jr., Karen F. Gaines, C. S. Eldridge Dec 2002

Coastal Habitat Use By Wood Storks During The Non-Breeding Season, A. L. Bryan Jr., Karen F. Gaines, C. S. Eldridge

Karen F. Gaines

We documented roosting and foraging habitat use by Wood Storks during the post-breeding season in the coastal zone of Georgia from 1994-1998. Larger, more persistent aggregations of roosting storks typically oc- curred in enclosed wetlands on large estuarine islands. Smaller, more ephemeral aggregations tended to occur on salt marsh/upland ecotones, where storks appeared to be waiting for local conditions (tide levels) to become suit- able for foraging. Examination of habitat types within a 2-km radius of the larger (mean > 10 storks/survey) vs. smaller (mean <10 storks/survey) roosts showed that surrounding habitat structure, including those used for for- aging, were similar. Foraging storks typically fed in close proximity (median = 0.5 km) to large roosts, much closer than storks using coastal wetlands during the breeding season. Tidal creeks were used almost exclusively as foraging habitat (92%). Storks and other wading birds were almost always present when the study bird arrived. The foraging patterns of study birds and four storks carrying radios suggested that storks often used the same foraging sites and/ or marsh systems in the non-breeding season. Coastal Wood Storks apparently selected roosting sites based on the presence of conspecifics, abundant local prey, or possibly as shelter from adverse weather conditions


Using Raccoons As An Indicator Species For Metal Accumulation Across Trophic Accumulation Across Trophic Levels: A Stable Isotope Approach, Karen F. Gaines, Christhopher S. Romanek, C. Shane Boring, Christine G. Lord, Michael Gochfeld, Joanna Burger Jan 2002

Using Raccoons As An Indicator Species For Metal Accumulation Across Trophic Accumulation Across Trophic Levels: A Stable Isotope Approach, Karen F. Gaines, Christhopher S. Romanek, C. Shane Boring, Christine G. Lord, Michael Gochfeld, Joanna Burger

Karen F. Gaines

: The fact that raccoons (Procyon lotor) are an opportunistic omnivore has severely complicated interpreta- tions of contaminant uptake patterns due to the inability to determine the trophic position an individual occupies. Moreover, few studies have examined the relationships between heavy metal bioaccumulation and trophic struc- ture, especially in the terrestrial environment. In this study, the stable isotopes of nitrogen were used to charac- terize the feeding habits of the raccoon at the population level and to determine whether metal burden was relat- ed to trophic feeding structure within a welldefined ecosystem. Raccoon populations were isotopically distinct, and significant positive relationships ...


Mineralization Of Clapper Rail Eggshell From A Contaminated Salt Marsh System, Alejandro Rodriguez-Navarro, Karen F. Gaines, Christopher S. Romanek, G. R. Masson Jan 2002

Mineralization Of Clapper Rail Eggshell From A Contaminated Salt Marsh System, Alejandro Rodriguez-Navarro, Karen F. Gaines, Christopher S. Romanek, G. R. Masson

Karen F. Gaines

The effect of contamination on eggshell mineralization has been studied for clapper rails (Rallus longirostris) inhabiting a contaminated salt marsh in coastal Georgia. To assess the impact of contaminants, the thickness, microstructure (crystal orientation), mineral composition, and chemistry of shell material were analyzed from a contaminated site and a nearby reference site using optical microscopy, X-ray diffraction, inductively coupled plasma mass spectrometry, and gas chromatography with electron capture detector. Eggshells from the contaminated site were generally thinner than those from the reference site. Also, eggshells from the contaminated site were abnormally brittle and contained anomalous microstructural attributes. The combination of ...


Ethnic Differences In Risk From Mercury Among Savannah River Fishermen, Joanna Burger, Karen F. Gaines, Michael Gochfeld Jan 2001

Ethnic Differences In Risk From Mercury Among Savannah River Fishermen, Joanna Burger, Karen F. Gaines, Michael Gochfeld

Karen F. Gaines

Fishing plays an important role in people's lives and contaminant levels in fish are a public health concern. Many states have issued consumption advisories; South Carolina and Georgia have issued them for the Savannah River based on mercury and radionuclide levels. This study examined ethnic differences in risk from mercury exposure among people consuming fish from the Savannah River, based on site-specific consumption patterns and analysis of mercury in fish. Among fish, there were significant interspecies differences in mercury levels, and there were ethnic differences in consumption patterns. Two methods of examining risk are presented: (1) Hazard Index (HI ...