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Risk Management and Critical Infrastructure Protection: Assessing, Integrating, and Managing Threats, Vulnerabilities and Consequences

Description: This report is meant to support congressional oversight by discussing, in more detail, what this task entails and issues that need to be addressed. In particular, the report defines terms (e.g., threat, vulnerability, and risk), discusses how they fit together in a systematic analysis, describes processes and techniques that have been used to assess them, and discusses how the results of that analysis can inform resource allocation and policy.
Date: July 17, 2007
Creator: Moteff, John
Partner: UNT Libraries Government Documents Department

The Science of Climate Change

Description: What constitutes 'dangerous anthropogenic interference' is a value judgment arrived at through a socio-political process, taking issues like equity and sustainability into account. Science provides key information needed to arrive at an informed judgment. However, that judgment is primarily a political one, and not a purely scientific decision. Such judgments are based on risk assessment, and lead to risk management choices by decision makers, about actions and policies.
Date: September 20, 2002
Creator: Makundi, Willy R.
Partner: UNT Libraries Government Documents Department

Environmental Risk Analysis: A Review of Public Policy Issues

Description: This report describes and analyzes key issues and legislative options related to risk analysis and risk management at EPA and considers the potential impact of proposed legislative approaches on EPA's rule-making process and final regulations. The report describes the history of EPA's use of risk analysis and then summarizes and analyzes issues and legislative proposals for increasing such use. Legislative activities in the 105th Congress are described. A list of selected references and an appendix where key terms are defined conclude the report.
Date: July 15, 1998
Creator: Schierow, Linda-Jo
Partner: UNT Libraries Government Documents Department

Accident Prevention under the Clean Air Act Section 112(r): Risk Management Planning by Propane Users and Internet Access to Worst-Case Accident Scenarios

Description: This report briefly describes two issues associated with EPA implementation of risk management planning requirements in the Clean Air Act Section 112(r): whether dealers and distributors of propane and other flammable fuels should be covered by the law, and whether electronic access to off-site consequence analyses (OCA), and especially worst-case analyses, should be restricted to avoid misuse by terrorists or criminals. These issues are addressed by S. 880, as reported, and H.R. 1301 in the 106th Congress. The statutory requrrements and EPA implementation to date also are described. Covered facilities must submit risk management plans by June 21, 1999. This product will be updated when events warrant. For information on the status of legislation, see CRS Issue Brief lB10004, Clean Air Act Issues in the 106th Congress.
Date: June 10, 1999
Creator: Schierow, Linda-Jo
Partner: UNT Libraries Government Documents Department

Ocean Piracy and Its Impact on Insurance

Description: This report examines the issue of piracy off the coast of East Africa in the Indian Ocean and the Gulf of Aden. The report looks into the impact of such piracy on the insurance industry and explains the available options for Congress to mitigate piracy's negative effects on the industry.
Date: December 3, 2008
Creator: King, Rawle O.
Partner: UNT Libraries Government Documents Department

Ocean Piracy and Its Impact on Insurance

Description: This report examines the issue of piracy off the coast of East Africa in the Indian Ocean and the Gulf of Aden. The report looks into the impact of such piracy on the insurance industry and explains the available options for Congress to mitigate piracy's negative effects on the industry.
Date: February 6, 2009
Creator: King, Rawle O.
Partner: UNT Libraries Government Documents Department

Standardized approach for developing probabilistic exposure factor distributions

Description: The effectiveness of a probabilistic risk assessment (PRA) depends critically on the quality of input information that is available to the risk assessor and specifically on the probabilistic exposure factor distributions that are developed and used in the exposure and risk models. Deriving probabilistic distributions for model inputs can be time consuming and subjective. The absence of a standard approach for developing these distributions can result in PRAs that are inconsistent and difficult to review by regulatory agencies. We present an approach that reduces subjectivity in the distribution development process without limiting the flexibility needed to prepare relevant PRAs. The approach requires two steps. First, we analyze data pooled at a population scale to (1) identify the most robust demographic variables within the population for a given exposure factor, (2) partition the population data into subsets based on these variables, and (3) construct archetypal distributions for each subpopulation. Second, we sample from these archetypal distributions according to site- or scenario-specific conditions to simulate exposure factor values and use these values to construct the scenario-specific input distribution. It is envisaged that the archetypal distributions from step 1 will be generally applicable so risk assessors will not have to repeatedly collect and analyze raw data for each new assessment. We demonstrate the approach for two commonly used exposure factors--body weight (BW) and exposure duration (ED)--using data for the U.S. population. For these factors we provide a first set of subpopulation based archetypal distributions along with methodology for using these distributions to construct relevant scenario-specific probabilistic exposure factor distributions.
Date: March 2003
Creator: Maddalena, Randy L.; McKone, Thomas E. & Sohn, Michael D.
Partner: UNT Libraries Government Documents Department

Bioavailability: implications for science/cleanup policy

Description: This paper examines the role of bioavailability in risk assessment and cleanup decisions. Bioavailability refers to how chemicals ''behave'' and their ''availability'' to interact with living organisms. Bioavailability has significant implications for exposure risks, cleanup goals, and site costs. Risk to human health and the environment is directly tied to the bioavailability of the chemicals of concern.
Date: December 1, 1998
Creator: Denit, Jeffery & Planicka, J. Gregory
Partner: UNT Libraries Government Documents Department

Environmental Risk and Cost-Benefit Analysis: A Review of Proposed Legislative Mandates, 1993-1998

Description: Between 1993 and 1998 Congress considered many proposals that aimed to increase or improve the use of risk analysis by federal agencies, especially in developing environmental rules. This report describes differences and similarities among selected provisions of key proposals: Senate-passed Johnston amendments to S. 171 and S. 2019 in the 103rd Congress; S. 343, as reported by the Committee on the Judiciary, in the 104th Congress; House-passed H.R. 9 in the 104th Congress; S. 981, as reported by the Committee on Governmental Affairs, in the 105th Congress, and S. 1728, as introduced, in the 105th Congress.
Date: January 22, 1999
Creator: Schierow, Linda-Jo
Partner: UNT Libraries Government Documents Department

Denial of Risk: the Effects of Intentional Minimization on Risk Assessments for Psychopathic and Nonpsychopathic Offenders

Description: Risk assessments for offenders often combine past records with current clinical findings from observations, interviews, and test data. Conclusions based on these risk assessments are highly consequential, sometimes resulting in increased criminal sentences or prolonged hospitalization. Offenders are therefore motivated to intentionally minimize their risk scores. Intentional minimization is especially likely to occur in offenders with high psychopathic traits because goal-directed deception is reflected in many of the core traits of the disorder, such as manipulativeness, glibness, and superficial charm. However, this connection appears to be based on the conceptual understanding of psychopathy, and it has rarely been examined empirically for either frequency or success. The current study examined the connection between psychopathic traits and the intentional minimization of risk factors using a sentenced jail sample. In general, offenders were able to effectively minimize risk on the HCR-20 and SAQ, while the PICTS, as a measure of cognitive styles, was more resistant to such minimization. Psychopathic traits, especially high interpersonal facet scores, led to greater minimization using a repeated measure, simulation design. Important differences in the willingness and ability to use deception were found based on (a) the content of subscales, and (b) the mode of administration (i.e., interview vs. self-report). The important implications of this research are discussed for risk assessment procedures regarding likely areas of deception and its detection. It also informs the growing literature on the connection between psychopathic traits and deception.
Date: August 2013
Creator: Gillard, Nathan D.
Partner: UNT Libraries

Shortened in Vivo Bioconcentration Factor Testing in Cyprinus Carpio

Description: Bioconcentration factor testing serves as the most valuable surrogate for the assessment of bioaccumulation. The assessment of potentially harmful chemicals is crucial to not only the health of aquatic environments, but to humans as well. Chemicals that possess the ability to persist in the environment or that have the potential to bioaccumulate, pose a greater risk to organisms that are exposed to these chemicals. The Organization for Economic Cooperation and Development Guideline 305 outlines specific protocols to run an accurate and reliable aquatic flow-through test. However, since its adoption in 1996, very few changes have been made to accommodate the endeavor to lowering the amount of test species to run one of these said tests. Running an aquatic flow-through test, according to 305, takes much time and money as well as numerous amounts of fish. Such burdens can be eliminated through simple modifications to the standard protocols. In this study, we propose an abbreviated study design for aquatic bioconcentration testing which effectively alleviates the burdens of running a flow-through test. Four chemicals were used individually to evaluate the usefulness of the proposed shortened design; 4-Nonyphenol, Chlorpyrifos, Musk Xylene, and DDT. The study consisted of exposing Cyprinus carpio for 7 days followed by 7 days of depuration, for a total of a 14-day study. Our results for each of the four compounds are consistent with literature values, thus, demonstrating that BCFk can be accurately predicted in an abbreviated in vivo test.
Date: December 2013
Creator: Cantu, Mark
Partner: UNT Libraries

Comparison of the bioavailability of elemental waste laden soils using in vivo and in vitro analytical methodology and refinement of exposure/dose models. 1998 annual progress report

Description: 'The authors hypotheses are: (1) the more closely the synthetic, in vitro, extractant mimics the extraction properties of the human digestive bio-fluids, the more accurate will be the estimate of an internal dose; (2) performance can be evaluated by in vivo studies with a rat model and quantitative examination of a mass balance, calculation and dose estimates from model simulations for the in vitro and in vivo system; and (3) the concentration of the elements Pb, Cd, Cr and selected Radionuclides present in the bioavailable fraction obtained with a synthetic extraction system will be a better indicator of contaminant ingestion from a contaminated soil because it represents the portion of the mass which can yield exposure, uptake and then the internal dose to an individual. As of April 15, 1998, they have made significant progress in the development of a unified approach to the examination of bioavailability and bioaccessibility of elemental contamination of soils for the ingestion route of exposure. This includes the initial characterization of the soil, in vitro measurements of bioaccessibility, and in vivo measurements of bioavailability. They have identified the basic chemical and microbiological characteristics of waste laden soils. These have been used to prioritize the soils for potential mobility of the trace elements present in the soil. Subsequently they have employed a mass balance technique, which for the first time tracked the movement and distribution of elements through an in vitro or in vivo experimental protocol to define the bioaccessible and the bioavailable fractions of digested soil. The basic mass balance equation for the in vitro system is: MT = MSGJ + MIJ + MR. where MT is the total mass extractable by a specific method, MSGJ, is the mass extracted by the saliva and the gastric juices, MIJ is the mass extracted by the intestinal ...
Date: June 1, 1998
Creator: Lioy, P.J.; Gallo, M.; Georgopoulos, P.; Tate, R. & Buckley, B.
Partner: UNT Libraries Government Documents Department

Mechanism involved in trichloroethylene-induced liver cancer: Importance to environmental cleanup. 1997 annual progress report

Description: 'The Pacific Northwest National Lab. was awarded ten (10) Environmental Management Science Program (EMSP) research grants in Fiscal Year 1996. This section gives a summary of how each grant is addressing significant DOE cleanup issues, including those at the Hanford Site. The technical progress made to date in each of these research projects is addressed in more detail in the individual progress reports contained in this document. This research is primarily focused in three areas-Tank Waste Remediation, Soil and Groundwater Cleanup, and Health Effects.'
Date: June 1, 1997
Creator: Bull, R.J.
Partner: UNT Libraries Government Documents Department

Mechanism involved in trichloroethylene-induced liver cancer: Importance to environmental cleanup. 1998 annual progress report

Description: 'The objective of this project is to develop critical data for changing risk-based clean-up standards for trichloroethylene (TCE). The project is organized around two interrelated tasks: Task 1 addresses the tumorigenic and dosimetry issues for the metabolites of TCE that produce liver cancer in mice, dichloroacetate (DCA) and trichloroacetate (TCA). Early work had suggested that TCA was primarily responsible for TCE-induced liver tumors, but several, more mechanistic observations suggest that DCA may play a prominent role. This task is aimed at determining the basis for the selection hypothesis and seeks to prove that this mode of action is responsible for TCE-induced tumors. This project will supply the basic dose-response data from which low-dose extrapolations would be made. Task 2 seeks specific evidence that TCA and DCA are capable of promoting the growth of spontaneously initiated cells from mouse liver, in vitro. The data provide the clearest evidence that both metabolites act by a mechanism of selection rather than mutation. These data are necessary to select between a linear (i.e. no threshold) and non-linear low-dose extrapolation model. As of May of 1998, this research has identified two plausible modes of action by which TCE produces liver tumors in mice. These modes of action do not require the compounds to be mutagenic. The bulk of the experimental evidence suggests that neither TCE nor the two hepatocarcinogenic metabolites of TCE are mutagenic. The results from the colony formation assay clearly establish that both of these metabolites cause colony growth from initiated cells that occur spontaneously in the liver of B 6 C 3 F 1 mice, although the phenotypes of the colonies differ in the same manner as tumors differ, in vivo. In the case of DCA, a second mechanism may occur at a lower dose involving the release of insulin. This observation ...
Date: June 1, 1998
Creator: Bull, R.J.; Thrall, B.D.; Sasser, L.B.; Miller, J.H. & Schultz, I.R.
Partner: UNT Libraries Government Documents Department

Environmental analysis of endocrine disrupting effects from hydrocarbon contaminants in the ecosystem. 1997 annual progress report

Description: 'The overall objective of the basic research grant is to characterize the potential of common hydrocarbon contaminants in ecosystems to act as endocrine disruptors. The three major lines of research include (1) a biotechnology based screening system to identify potential hormone mimics and antagonists; (2) an animal screening system to identify biomarkers of endocrine effects. and (3) a literature review to identify compounds at a variety of DOE sites that need to be examined for endocrine disrupting effects. By relating results obtained from this research project to contamination problems at various DOE sites. CBR will provide data and information on endocrine disrupting contaminants to DOE for consideration in risk analyses for determining clean-up levels and priorities needed at the sites.'
Date: January 1, 1997
Partner: UNT Libraries Government Documents Department

Environmental analysis of endocrine disrupting effects from hydrocarbon contaminants in the ecosystem. 1998 annual progress report

Description: 'The objective of this project is to determine how environmental contaminants, namely hydrocarbons, can act as hormones or anti-hormones (i.e., environmental hormones) in different species present in aquatic ecosystems. Species of particular focus are those which can serve as sentinel species (e.g., amphibians) and, thus, provide early warning signals for more widespread impacts on an ecosystem and its wildlife and human inhabitants. This reports the progress of 1.5 years of a three-year grant awarded to the Tulane/Xavier Center for Bioenvironmental Research (CBR). A growing body of evidence suggests that chemicals in the environment can disrupt the endocrine system of animals (i.e., wildlife and humans) and adversely impact the development of these species. Because of the multitude of known endocrine-disrupting chemicals and the numerous industrial and government sectors producing these chemicals, almost every federal agency has initiated research on the endocrine effects of chemicals relevant to their operations. This study represents the Department of Energy (DOE) Basic Energy Sciences'' only research on the impacts of endocrine-disrupting chemicals. The activities employed by this project to determine these impacts include development of biotechnology screens (in vitro), animal screens (in vivo), and other analyses of aquatic ecosystem biomarkers of exposure. The results from this study can elucidate how chemicals in the environment, including those from DOE activities, can signal (and alter) the development of a number of species in aquatic ecosystems. These signals can have detrimental impacts not only on an organismal level, but also on community, population, and entire ecosystem levels, including humans.'
Date: June 1, 1998
Creator: McLachlan, J.
Partner: UNT Libraries Government Documents Department

Environmentally-induced malignancies: An in vivo model to evaluate the health impact of chemicals in mixed waste. 1997 annual progress report

Description: 'Occupational or environmental exposure to organic ligands, solvents, fuel hydrocarbons, and polychlorinated biphenyls is linked to increased risk of developing leukemia, a blood cancer. The long term health effects of exposure to complex mixtures of chemicals and radionuclides are of particular concern because their biologic effects may synergize to increase risk of malignancy. Increased understanding of steps in the progression pathway of a normal cell to a cancer cell is important for biomonitoring, risk assessment and intervention in exposed individuals. Leukemias are characterized by multiple genetic aberrations. Accumulation of multiple genomic changes may reflect genomic instability in the affected ceils. Thus agents that induce DNA damage or genomic instability may increase accumulation of genomic alterations, thereby predisposing cells to transformation. However, not all DNA damaging agents predispose to transformation. Other factors such as genetic susceptibility, cell and tissue response to genotoxicity and cytotoxicity, DNA repair, etc. will impact malignant progression. The author proposed a progression model (Figure 1) of environmentally-induced leukemia that can be evaluated using mouse models.'
Date: January 1, 1997
Creator: Pallavicini, M.
Partner: UNT Libraries Government Documents Department

Environmentally-induced malignancies: An in vivo model to evaluate the health impact of chemicals in mixed waste. 1998 annual progress report

Description: 'Increased risk of malignancy following exposure to genotoxic agents in the environment is a major public concern. Exposure to radiation, benzene, and organic solvents is associated with an increased risk of leukemia; however the mechanism of leukemogenesis is unknown. The authors postulate that chemical(s) that increase the rate of genomic instability and induce hematotoxicity will promote accumulation of genetically-damaged hematopoietic stem cells (hsc), and thus contribute towards development of environmentally-induced hematologic malignancy. They will use molecular and cellular approaches to establish the relationship between hematoxicity, genomic instability and production of genetically aberrant hsc and progeny in mice exposed to radiation, benzene and trichloroethylene (TCE). The goals of this project are to (1) determine whether recruitment of hsc into cycle by agents that induce hematotoxicity (i.e., pancytopenia, anemia) facilitates fixation of genetic damage in hsc exposed to environmental genotoxins in vivo. (2) Determine whether environmental genotoxins with leukemogenic potential disrupt hsc genomic integrity by inactivating cell cycle checkpoints. (3) Determine whether low dose exposures to agents that induce chronic pancytopenia/anemia and/or cyclic hemopoiesis increase fixation of genetic damage in hsc. Increased understanding of the relationship between genotoxicity, hematotoxicity and genomic instability will (a) lend insight into mechanisms underlying environmental-induction of leukemic progression, (b) facilitate development of a rationale to identify chemical combinations which synergize to increase or decrease leukemogenic potential, and (c) provide opportunities to optimize approaches for biomonitoring and risk assessment. This report summarizes work after 1.5 year of a 3 year project. Accomplishments to-date include demonstration that the cycling status of hemopoietic stem cells at the time of genotoxin exposure alters the frequency and persistence of genetically damaged hemopoietic stem cells and associated progeny (Aim 1), development of assays to measure genomic instability in hemopoietic stem cells and associated progenitors (Aim 2) and quantification of genomically aberrant hsc and ...
Date: June 1, 1998
Creator: Pallavicini, M.
Partner: UNT Libraries Government Documents Department

Improved risk estimates for carbon tetrachloride. 1998 annual progress report

Description: 'The overall purpose of these studies is to improve the scientific basis for assessing the cancer risk associated with human exposure to carbon tetrachloride. Specifically, the toxicokinetics of inhaled carbon tetrachloride is being determined in rats, mice and hamsters. Species differences in the metabolism of carbon tetrachloride by rats, mice and hamsters is being determined in vivo and in vitro using tissues and microsomes from these rodent species and man. Dose-response relationships will be determined in all studies. The information will be used to improve the current physiologically based pharmacokinetic model for carbon tetrachloride. The authors will also determine whether carbon tetrachloride is a hepatocarcinogen only when exposure results in cell damage, cell killing, and regenerative cell proliferation. In combination, the results of these studies will provide the types of information needed to enable a refined risk estimate for carbon tetrachloride under EPA''s new guidelines for cancer risk assessment.'
Date: June 1, 1998
Creator: Benson, J.M.; Springer, D.L. & Thrall, K.D.
Partner: UNT Libraries Government Documents Department