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Molecular Characterization of a Novel Heavy Metal Uptake Transporter from Higher Plants and its Potential for Use in Phytoremediation - Final Report

Description: Heavy metal toxicity poses major environmental and health problems, and heavy metals are more difficult to remediate than chemical contaminants, which can be degraded by microorganisms. Cadmium and arsenic, for example, are non-essential heavy metals which are toxic to living cells at very low concentrations. Cd 2+ ions displace Ca2+ or Zn2+ in proteins and can cause oxidative stress, while arsenic also causes oxidative stress damage and is a well known carcinogen.
Date: October 1, 2000
Creator: Schroeder, J.
Partner: UNT Libraries Government Documents Department

Developmental Effects of a Non-Dioxin-Like Polychlorinated Biphenyl Mixture on Zebrafish (Danio rerio)

Description: PCBs are synthetic organic compounds known for their toxicity to many organisms and are notorious for having large discrepancies between measured and nominal concentrations. Historically thought to be less toxic, non-dioxin-like (NDL) PCBs represent the majority of congeners and are capable of eliciting neurotoxic effects. NDL-PCBs remain understudied, including their effects on aquatic organisms. In the first study, I collected extensive chemistry data and data on neurobehavioral and cardiac e… more
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Date: July 2023
Creator: Green, Corey
Partner: UNT Libraries
open access

Toxicity Bioassays for Ecological Risk Assessment in Arid and Semiarid Ecosystems. Reviews Environmental Contamination and Toxicology 168:43-98.

Description: This paper discusses current limitations for performing ecological risk assessments in dry environments (i.e., ecosystems that are characteristic of many DOE Facilities) and presents novel approaches to addressing ecological risk in such systems.
Date: February 2001
Creator: Markwiese, J. T.; Ryti, R. T.; Hooten, M. M.; Michael, D. I. & Hlohowskyj, I.
Partner: UNT Libraries Government Documents Department
open access

Final Report - Phase II - Biogeochemistry of Uranium Under Reducing and Re-oxidizing Conditions: An Integrated Laboratory and Field Study

Description: Our understanding of subsurface microbiology is hindered by the inaccessibility of this environment, particularly when the hydrogeologic medium is contaminated with toxic substances. Past research in our labs indicated that the composition of the growth medium (e.g., bicarbonate complexation of U(VI)) and the underlying mineral phase (e.g., hematite) significantly affects the rate and extent of U(VI) reduction and immobilization through a variety of effects. Our research was aimed at elucidatin… more
Date: September 28, 2006
Creator: Peyton, Brent & Sani, Rajesh
Partner: UNT Libraries Government Documents Department
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Radiotoxicity of Injected SR89 for Rats, Mice and Rabbits. Part IV. The Hematological Effects of Enterally and Parenterally Administered Strontimu 89 in Mamals

Description: Hematological studies of the peripheral blood of rabbits, rats, and mice, after the intraperitoneal or stomach tube administration of Sr89 in doses from 0.015 to 14.4 uc/g for varying periods up to 108 weeks, are reported.
Date: unknown
Creator: Simmons, Eric L. & Jacobson, Leon O.
Partner: UNT Libraries Government Documents Department
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Responses of Pristina leidyi Smith 1896 (Naididae: Oligochaeta) to Cadmium, Vanadium, and Some Environmental Factors

Description: Concern over sediment toxicity has increased the need for toxicity test information with organisms that inhabit sediments. Oligochaetes are exposed to toxicants through feeding and direct body contact with aquatic sediments. Chronic testing with oligochaetes has historically focused on tubificids with test lengths of one year or more to encompass several generations. Most naidid oligochaetes have generation times of three to seven days and could provide chronic information in a matter of weeks.… more
Date: May 1990
Creator: Smith, David P. (David Paul), 1956-
Partner: UNT Libraries
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Identifying Biomarkers and Mechanisms of Toxic Metal Stress with Global Proteomics

Description: Hg is a wide-spread contaminant in the environment and is toxic in all of its various forms. Data suggest that RHg+ and Hg2+ are toxic in two ways. At low levels, Hg species appear to disrupt membrane-bound respiration causing a burst of reactive oxygen species (ROS) that further damage the cell. At higher Hg concentrations, RHg+ and Hg2+ may form adducts with cysteine- and selenocysteine-containing proteins in all cellular compartments resulting in their inactivation. Although these mechansims… more
Date: April 16, 2012
Creator: Miller, Susan M.
Partner: UNT Libraries Government Documents Department
open access

Annual Waste Minimization Summary Report, Calendar Year 2010, U.S. Environmental Protection Agency Identification No. NV3890090001

Description: This report summarizes the waste minimization efforts undertaken by National Security TechnoIogies, LLC, for the U. S. Department of Energy, National Nuclear Security Administration Nevada Site Office (NNSA/NSO), during calendar year 2010. The NNSA/NSO Pollution Prevention Program establishes a process to reduce the volume and toxicity of waste generated by NNSA/NSO activities and ensures that proposed methods of treatment, storage, and/or disposal of waste minimize potential threats to human h… more
Date: January 30, 2011
Creator: Haworth, D.M.
Partner: UNT Libraries Government Documents Department
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Response of Freshwater and Saltwater Toxicity Test Species to Calcium and Salinity Concentrations Encountered in Toxicity Tests

Description: The responses of freshwater (Daphnia magna. Pimephales promelas) and saltwater (Mysidopsis bahia. Cyprinodon variegatus) toxicity test species to elevated calcium concentrations and changing salinity conditions were investigated. The use of salinity as a criterion for selection between saltwater and freshwater test species was investigated by conducting both calcium and salinity toxicity tests. Salinity was determined to be an inappropriate criterion under conditions encountered in this study.
Date: 1989
Creator: Price, Edmund E., 1954-
Partner: UNT Libraries
open access

Chromium Toxicity Test for Fall Chinook Salmon (Oncorhynchus tshawytscha) Using Hanford Site Groundwater: Onsite Early Life-Stage Toxicity Evaluation

Description: The objective of this study was to evaluate site-specific effects for early life-stage (eyed eggs to free swimming juveniles) fall chinook salmon that might be exposed to hexavalent chromium from Hanford groundwater sources. Our exposure conditions included hexavalent chromium obtained from Hanford groundwater wells near the Columbia River, Columbia River water as the diluent, and locally adapted populations of fall chinook salmon. This report describes both a 96-hr pretest using rainbow trout … more
Date: July 10, 2001
Creator: Patton, Gregory W.; Dauble, Dennis D.; Chamness, Michele A.; Abernethy, Cary S. & McKinstry, Craig A.
Partner: UNT Libraries Government Documents Department
open access

The Toxicity of Fluorine

Description: The following report discusses the toxicity of fluorine as described in literature on fluorine intoxication and case studies of Roholm's experimental observations.
Date: 1943
Creator: Ferry, J. L.
Partner: UNT Libraries Government Documents Department
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Solvent Effects and Bioconcentration Patterns of Antimicrobial Compounds in Wetland Plants

Description: This study looked at effects of organic solvents dimethylsulfoxide, dimethylformamide and acetone at 0.01%, 0.05% and 0.1% concentration on germination and seedling development wetland plants. Even at 0.01% level, all solvents affected some aspect of seed germination or seedling growth. Acetone at 0.01% was least toxic. Root morphological characteristics were most sensitive compared to shoot morphological characteristics. This study also looked at bioconcentration patterns of antimicrobial comp… more
Date: May 2011
Creator: Adhikari, Sajag
Partner: UNT Libraries
open access

Structure-Activity Studies of Halopyrethroids

Description: The structures of the new pyrethroids were elucidated utilizing nuclear magnetic spectroscopy and elemental analysis. The biological activity of the pyrethroids has been evaluated for houseflies and yellow fever mosquitoes. A correlation of increase in rapid knockdown and toxicity with decrease in size of halogen has been made. The most effective compound, the difluorovinyl ester, has a toxicity of 123 times greater than pyrethrins. This degree of toxicity has not previously been reported for a… more
Date: December 1974
Creator: Brown, Dale Gordon
Partner: UNT Libraries
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Interaction of Actinide Species with Microorganisms & Microbial Chelators: Cellular Uptake, Toxicity, & Implications for Bioremediation of Soil & Ground Water.

Description: Microorganisms influence the natural cycle of major elements, including C, N, P, S, and transition metals such as Mn and Fe. Bacterial processes can also influence the behavior of actinides in soil and ground water. While radionuclides have no known biological utility, they have the potential to interact with microorganisms and to interfere with processes involving other elements such as Fe and Mn. These interactions can transform radionuclides and affect their fate and transport. Organic acids… more
Date: March 28, 2006
Creator: Hakim Boukhalfa Mary, P. Neu Alvin Crumbliss
Partner: UNT Libraries Government Documents Department
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Acute Radiotoxicity of (BA-LA)140 in Rats and Mice : Part I. Preparation and Administration of the Emitters

Description: Barium 140 and its daughter, lanthanum 140, were obtained from uranium fission. The composition of the solutions used in animal studies is given a procedure for delivering toxic doses to small animals and methods for preparing animal tissues for radioactivity measurements are described.
Date: unknown
Creator: Finkle, R.; Snyder, R. & Tompkins, P.
Partner: UNT Libraries Government Documents Department
open access

Toxicology Studies on Lewisite and Sulfur Mustard Agents: Two-Generation Reproduction Study of Lewisite in Rats Final Report

Description: Occupational health standards have not been established for Lewisite [bis(2-chlorethyl)arsine], a potent toxic vesicant which reacts with the sulfhydryl groups of proteins through its arsenic group. The purposes of this study were to determine the reproductive consequences and dose~response of continuing Lewisite exposure of parental males and females and their offspring in a 42-week two-generation study. Solutions of Lewisite were prepared for administration by diluting the neat agent with ses… more
Date: July 15, 1989
Creator: Sasser, L. B.; Cushing, J. A.; Kalkwarf, D. R.; Mellick, P. W. & Buschbom, R. L.
Partner: UNT Libraries Government Documents Department
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The Effects of Neonicotinoid Exposure on Embryonic Development and Organ Mass in Northern Bobwhite Quail

Description: Since their emergence in the early 1990s, neonicotinoid use has increased exponentially to make them the world's most prevalent insecticides. Although there is considerable research concerning the lethality of neonicotinoids, their sub-lethal and developmental effects are still being explored, especially with regards to non-mammalian species. The goal of this research was to investigate the effects of the neonicotinoid imidacloprid on the morphological and physiological development of northern … more
Date: May 2016
Creator: Gobeli, Amanda
Partner: UNT Libraries
open access

The Effects of Glyphosate Based Herbicides on Chick Embryo Development

Description: Glyphosate based herbicides are among the most widely used herbicides in the world. The purpose of this study was to determine developmental toxicity of glyphosate, the active ingredient in the common herbicide Roundup, on developing chicken embryos. Few studies have examined toxic effects of glyphosate alone versus the full compound formulations of Roundup, which include adjuvants and surfactants. Adjutants and surfactants are added to aid in solubility and absorption of glyphosate. In thi… more
Date: August 2013
Creator: Winnick, Blake Edward
Partner: UNT Libraries
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