bluuebunny/crossref_metadata_2025 huggingface dataset:
Risk Perception Among Nuclear Power Plant Personnel: A Survey
Authors: Kivimäki Mika , Kalimo Raija
Published: May 2006

This study investigated risk perception, well‐being, and organizational commitment among nuclear power plant personnel. The study group, 428 employees from a nuclear power plant, completed a questionnaire which included the same questions as those in previous surveys on risk perception of lay persons and industrial workers. Hazards at work were not seen as a sizable problem by nuclear power plant personnel. The study group estimated the safety of nuclear power plants better and the possibility of a serious nuclear accident as more unlikely than the general public. Compared to employees in other industrial companies, the overall perceived risks at work among plant personnel did not exceed the respective perceptions of the reference groups. Risk‐related attitudes did not explain well‐being among plant personnel, but the relationship between the perceived probability of a serious nuclear accident at work and organizational commitment yielded to a significant correlation: Those plant workers who estimated the likelihood of an accident higher were less committed to the organization.
Radon Testing Behavior in a Sample of Individuals with High Home Radon Screening Measurements
Authors: Field R. William , Kross Burton C. , Vust La Verle J.
Published: May 2006

Although radon exposure has been identified as the second leading cause of lung cancer, fewer than 6% of U.S. homeowners test their homes for radon. This report examines participants’follow‐up radon testing behavior subsequent to receiving an initial screening radon level greater than 20 pCi/L. Sixty‐two participants in the Iowa State‐Wide Rural Radon Screening Survey who had radon screening measurements over 20 pCi/L were questioned by phone survey 3 months after receipt of their radon screening result to assess: whether participants were aware of radon's health risk; if participants recalled the radon screening results; how participants perceived the relative health risk of radon and whether participants planned follow‐up radon testing. Only 19% of the respondents specifically identified lung cancer as the possible adverse health outcome of high radon exposure, and the majority of participants underestimated the health risks high radon levels pose when compared to cigarettes and x‐rays. In addition, less than one third (29%)of the participants actually remembered their radon screening level within 10 pCi/L 3 months after receiving their screening results. Only 53% of the individuals correctly interpreted their screening radon level as being in the high range, and only 39% of the participants planned follow‐up radon measurements. Receipt of radon screening test results indicating high radon levels was not an adequate motivational factor in itself to stimulate further radon assessment or mitigation. Our findings suggest that free radon screening will not result in a dramatic increase in subsequent homeowner initiated remediation or further recommended radon testing.
Perceptions of Nuclear and Other Risks in Japan and the United States
Authors: Hinman George W. , Rosa Eugene A. , Kleinhesselink Randall R. , Lowinger Thomas C.
Published: May 2006

As part of a study of nuclear power development in Japan and the United States, surveys of perceptions of risk toward 30 activities, substances, and technologies have been carried out in the Pacific Northwest and Tokyo, Japan. The results show that people in both countries have the highest level of dread toward nuclear waste disposal, nuclear accidents, and nuclear war, greater even than their dread of crime and AIDS. In addition to comparisons of dread, the paper also discusses similarities and differences between Japanese and American responses for other dimensions of risk perception.
The U.S. EPA Geographic Information System for Mapping Environmental Releases of Toxic Chemical Release Inventory (TRI) Chemicals
Authors: Stockwell John R. , Sorensen Jerome W. , Eckert James W. , Carreras Edward M.
Published: May 2006

This study characterizes the environmental releases of toxic chemicals of the Toxic Chemical Release Inventory (TRI) in the southeastern United States by using the U.S. Environmental Protection Agency (EPA) Geographic Information System (GIS) to map them. These maps show that the largest quantities of TRI releases in the Southeast are usually near densely populated areas. This GIS mapping approach takes the first steps in defining those areas in the region which may be potential exposure zones and which could be strategic targets for future risk screening efforts in this geographic area.
Predicting Loss of Life in Cases of Dam Failure and Flash Flood
Authors: DeKay Michael L. , McClelland Gary H.
Published: May 2006

This paper improves upon previous attempts to predict loss of life (LOL) from severe flooding events. An expression for LOL in terms of warning time (WT), the size of the population at risk (PAR), and the forcefulness of the flood waters (Force) is derived from the historical record of dam failures and flash flood cases via logistic regression. There is no evidence for an effect of prior flooding experience or an interaction between WT and PAR, as has been suggested elsewhere. Guidelines are suggested for the proper use of the final equations and the findings are discussed in relation to a theoretical model of flood fatalities.
Armitage‐Doll Two‐Stage Model: Implications and Extension
Authors: Chen Chao W.
Published: May 2006

The objective of this paper is twofold: (1) to provide insight on the simplified MVK model of carcinogenesis (a model proposed by Moolgavkar and colleagues) by revealing the relationship between the Armitage‐Doll two‐stage model and the simplified MVK model; and (2) to extend the Armitage‐Doll two‐stage model to one with time‐varying (piece‐wise constant) parameters. It is shown that the simplified MVK model is a special case of the Armitage‐Doll two‐stage model, and many applications of the simplified MVK model involving intermittent exposures or exposures to different compounds in different time periods can be derived easily from the Armitage‐Doll two‐stage model with piece‐wise constant parameters. The limitations of the Armitage‐Doll two‐stage model are discussed.
The Social Construction of Risk in a Rural Community: Responses of Local Residents to the 1990 Hagersville (Ontario) Tire Fire
Authors: Eyles John , Taylor S. Martin , Baxter Jamie , Sider Doug , Willms Dennis
Published: May 2006

This paper presents the findings of research relating to the 1990 Hagersville (Ontario) tire fire. After reviewing the literature on risk and risk perception, it begins by describing the event as well as the community in which it occurred. The reasons for adopting a qualitative research design are then established practical, conceptual, and methodological. The residents' accounts of the fire, evacuation, and aftermath in terms of concerns, anxieties, and responses are described. Five themes emerge: economic, community, health, environmental, and governance. The paper concludes by putting forward a case study‐derived model of risk appraisal and management, and by relating the findings to policy issues.
Conditional Influence Diagrams in Risk Management
Authors: Hong Yuan , Apostolakis George
Published: May 2006

This paper introduces conditional influence diagrams into risk management. A contaminated‐site cleanup involving two stakeholders is used as a hypothetical case study. The treatment choices must satisfy several conflicting objectives. Any decision made by one stakeholder will affect the choices of the other stakeholder. In building the influence diagrams for each of the stakeholders, the logical relationship of all relevant factors is determined and the values of these factors are analyzed. The influence diagram for each stakeholder is conditional on the options available to the other stakeholder. The influence diagrams are, then, used to evaluate the possible choices of each stakeholder based on decision options of the other stakeholder. These results are analyzed using game theory methods to gain insights useful to risk management and to demonstrate how mutual trust and cooperation can lead to decisions benefiting both stakeholders.
Decidedly Different: Expert and Public Views of Risks from a Radioactive Waste Repository
Authors: Flynn James , Slovic Paul , Mertz C. K.
Published: May 2006

A questionnaire with items that had been used in a national survey of the general public was administered to persons attending an American Nuclear Society meeting. The items asked about risks associated with high‐level nuclear waste (HLNW), trust in nuclear‐waste program managers, costs and benefits of a repository project, and images of a HLNW repository. The results suggest that nuclear industry experts may have very different opinions from the general public about most of these items and their images of a repository indicate a vastly different conceptual framework within which their opinions are formed.
Perceived Risks of Radioactive Waste Transport Through Oregon: Results of a Statewide Survey
Authors: MacGregor Donald , Slovic Paul , Mason Robert G. , Detweiler John , Binney Stephen E. , Dodd Brian
Published: May 2006

Transportation of hazardous materials, and particularly radioactive wastes, on public highways has become an important risk management issue. The unfavorability of public attitudes regarding hazardous and nuclear wastes signals the potential for strong public opposition to programs for transporting these materials. This paper presents the results of a survey conducted to assess public reactions to a long‐term nuclear waste transport program planned to follow a route through a portion of rural Oregon. The survey assessed a number of key risk perception issues, including perceived health and safety risks of nuclear waste transport, relative risks of transport vs. storage at an existing site, trust in state officials, and satisfaction with life in communities along the transport route. The survey identified a number of attitudes and concerns that need to be understood and considered by those in charge of designing and implementing the waste‐transportation program.
Risk Communication in The Netherlands: The Monitored Introduction of the EC “Post‐Seveso” Directive
Authors: Van Eijndhoven Joseé CM. , Weterings Rob A.P.M. , Worrell Cor W. , de Boer Joop , van der Pligt Joop , Stallen Pieter‐Jan M.
Published: May 2006

Implementation of article 8.1 of the EC‐“Seveso” Directive (82/501/EC) is now under way in many countries in Europe. In The Netherlands, the implementation of the Directive started with a carefully monitored introduction of active information provision at two sites (Dordrecht and Elst). This introduction was supported by a multidisciplinary research group. This group helped to develop the risk communication program and also played a role in the evaluation of the program. This paper describes these processes and their evaluation. We will focus on the design of the risk communication programs and the effects of the programs on knowledge and attitudes of the local target groups. This effort and its results clearly started an institutional learning process involving governmental bodies at several organizational levels (local, regional, and national), and industrial organizations (individual firms and organizations of industries). Monitoring the design, the implementation, and the effects of active information provision proves an effective means to gain experience with the implementation of the Seveso Directive and could help to facilitate further implementation.
Managing Nuclear Waste from Power Plants
Authors: Keeney Ralph L. , von Winterfeldt Detlof
Published: May 2006

National strategies to manage nuclear waste from commercial nuclear power plants are analyzed and compared. The current strategy is to try to operate a repository at Yucca Mountain, Nevada, to dispose of high‐level nuclear waste underground. The main alternatives involve temporary above‐ground storage at a centralized facility or next to nuclear power plants. If either of these is pursued now, the analysis assumes that a repository will be built in 2100 for waste not subsequently put to use. The analysis treats various uncertainties: whether a repository at Yucca Mountain would be licensed, possible theft and misuse of the waste, innovations in repository design and waste management, the potential availability of a cancer cure by 2100, and possible future uses of nuclear waste. The objectives used to compare alternatives include concerns for health and safety, environmental and socioeconomic impacts, and direct economic costs, as well as equity concerns (geographical, intergenerational, and procedural), indirect economic costs to electricity ratepayers, federal government responsibility to manage nuclear waste, and implications of theft and misuse of nuclear waste. The analysis shows that currently building an underground repository at Yucca Mountain is inferior to other available strategies by the equivalent of $10,000 million to $50,000 million. This strongly suggests that this policy should be reconsidered. A more detailed analysis using the framework presented would help to define a new national policy to manage nuclear waste.
Environmental Hazards in the Chinese Public's Eyes
Authors: Jianguang Zhang
Published: May 2006

The People's Republic of China suffers each year from various environmental hazards. Although risk perception study has a 40‐year history in Europe and North America, little is known about risk perception in China. Previous studies of risk perception have primarily focused on unnatural hazards, but China has experinced many natural environmental hazards. Therefore, the Chinese public's perceptions of environmental hazard risks must be considered in order to support the IDNDR program. The Chinese public's perceptions of environmental hazards are similar to those of Europeans and North Americans, but different characteristics are observed.
The Effect of Product Safety Regulation on Safety Precautions
Authors: Viscusi W. Kip , Cavallo Gerald O.
Published: May 2006

This paper explores the means by which lighter safety regulations alter the precautionary behavior of 200 subjects in a field test of cigarette lighters with a child‐resistant feature. The new lighter design leads respondents to believe the lighters are safer, but there is no clear‐cut evidence that the effect on perceived risk levels is excessive. Using the estimated relationship between cigarette lighter risk perceptions and a variety of measures of precautions, this paper provides explicit estimates of the effect of regulations on precautionary behavior and on lighter safety. On balance, the child‐resistant feature will reduce fire‐related injuries by much more than any diminished precaution taking.
Urinary Excretion of Chromium Following Ingestion of Chromite‐Ore Processing Residues in Humans: Implications for Biomonitoring
Authors: Gargas Michael L. , Norton Robin L. , Harris Mark A. , Paustenbach Dennis J. , Finley Brent L.
Published: May 2006

Biomonitoring programs for urinary chromium (Cr) typically attempt to evaluate occupational exposure via the inhalation route. This study investigated whether Cr can be detected in the urine of people following the ingestion of soils that contain relatively high concentrations of chromium in chromite ore processing residue (COPR). To evaluate the reasonableness of using urinary monitoring to assess environmental exposure, six volunteers ingested 400 mg of soil/day (low‐dose group), two others ingested 2.0 g of soil/day (high‐dose group) for 3 consecutive days, and one person ingested a placebo on each of 3 days. The soil and COPR mixture contained concentrations of total chromium (Cr) and hexavalent chromium [Cr(VI)] of 103 ± 20 and 9.3 ± 3.8 mg/kg, respectively. Therefore, the low‐dose group ingested 41 μg Cr/day [including 3.7 μg Cr(VI)] and the high‐dose group ingested 206 μg Cr/day [including 18.6 μg Cr(VI)] on each of 3 consecutive days. All urine samples were collected and analyzed individually for total Cr on the day prior to dosing, during the 3 days of dosing, and up to the first void 48 h after the last dose. No significant increases in urinary Cr excretion were found when background excretion data were compared with data following each of the 3 days of dosing or in daily mean urine concentrations of the high‐ vs the low‐dose groups. It appears that Cr present in a soil and COPR mixture at Cr doses up to 200 μg/day is not sufficiently bioavailable for biomonitoring of urine to be informative. These results are consistent with previously published findings suggesting that incidental exposure to dusts and soils containing comparable levels of Cr will not result in increased concentrations of Cr in urine.
Use of Mechanistic Models to Estimate Low‐Dose Cancer Risks
Authors: Crump Kenny S.
Published: May 2006

The utility of mechanistic models of cancer for predicting cancer risks at low doses is examined. Based upon a general approximation to the dose‐response that is valid at low doses, it is shown that at low doses the dose‐response predicted by a mechanistic model is a linear combination of the dose‐responses for each of the physiological parameters in the model that are affected by exposure. This demonstrates that, unless the mechanistic model provides a theoretical basis for determining the dose‐responses for these parameters, the extrapolation of risks to low doses using a mechanistic model is basically “curve fitting,” just as is the case when extrapolating using statistical models. This suggests that experiments to generate data for use in mechanistic models should emphasize measuring the dose‐response for dose‐related parameters as accurately as possible and at the lowest feasible doses.
The Exact Formula for Tumor Incidence in the Two‐Stage Model
Authors: Kopp‐Schneider Annette , Portier Christopher J. , Sherman Claire D.
Published: May 2006

An exact formula for the tumor incidence rate in the usual two‐stage model of carcinogenesis is presented. This formula is simple and easily implemented on calculators and computers.
Dose‐Response Analysis Using Spreadsheets
Authors: Haas Charles N.
Published: May 2006

The task of fitting dose‐response models to experimental data can be performed using a spreadsheet with a built‐in optimization engine. This paper shows how the task of point and interval estimation can be performed using Microsoft EXCEL. A case study is presented on the carcinogenic dose‐response behavior of chloroform.
Significance of the Dermal Route of Exposure to Risk Assessment
Authors: Mattie David R. , Grabau John H. , McDougal James N.
Published: May 2006

The skin is a route of exposure that needs to be considered when conducting a risk assessment. It is necessary to identify the potential for dermal penetration by a chemical as well as to determine the overall importance of the dermal route of exposure as compared with inhalation or oral routes of exposure. The physical state of the chemical, vapor or liquid, the concentration, neat or dilute, and the vehicle, lipid or aqueous, is also important. Dermal risk is related to the product of the amounts of penetration and toxicity. Toxicity involves local effects on the skin itself and the potential for systemic effects. Dermal penetration is described in large part by the permeability constant. When permeability constants are not known, partition coefficients can be used to estimate a chemical's potential to permeate the skin. With these concepts in mind, a tiered approach is proposed for dermal risk assessment. A key first step is the determination of a skin‐to‐air or skin‐to‐medium partition coefficient to estimate a potential for dermal absorption. Building a physiologically‐based pharmacokinetic (PBPK) model is another step in the tiered approach and is useful prior to classical in vivo toxicity tests. A PBPK model can be used to determine a permeability constant for a chemical as well as to show the distribution of the chemical systemically. A detailed understanding of species differences in the structure and function of the skin and how they relate to differences in penetration rates is necessary in order to extrapolate animal data from PBPK models to the human. A study is in progress to examine anatomical differences for four species.
The Role of Modulated Gap Junctional Intercellular Communication in Epigenetic Toxicology
Authors: Trosko James E. , Chang Chia‐Cheng , Madhukar Burra V.
Published: May 2006

The normal development and health of all multicellular organisms, including the human being, depend on the adaptive maintenance of the integrity of the genetic information (e.g., DNA protective and repair mechanisms), as well as of the homeostatic and cybernetic regulatory systems within and between tissues. The primary focus of the past and current toxicological studies and risk assessment practices has been to ascertain and predict the “genotoxicity” of various physical and chemical agents. The paradigm of “carcinogen as mutagen,” while valuable for stimulating studies of the detection of mutagens and of their potential role in “causing” somatic and germ line diseases, has tended to blunt research on the role of nongenotoxic mechanisms in disease causation. This brief analysis will emphasize the need to consider the role of modulated gap junctional intercellular communication (GJIC) in any biological risk assessment model. It is based on the following assumptions and facts. Because gap junctions exist in all metazoans, they have been associated with the regulation of cell proliferation, development, differentiation, and the adaptive function of both excitable and nonexcitable coupled cells. A highly evolutionary conserved family of genes codes for proteins (connexins), which, as hexameric units (connexons), form membrane‐associated channels of gap junctions. Cells coupled by gap junctions will have their ions and small regulatory molecules equilibrated. Regulation of GJIC can be at the transcriptional, translational, or posttranslational levels. Transient down or up regulation of GJIC can be induced by endogenous or exogenous chemicals via many mechanisms at any of these three levels. Stable abnormal regulation has been associated with activated oncogenes, and normal regulation has been associated with several tumor suppressor genes. The dysfunction of these gap junctions might play a role in the actions of various toxic chemicals that have cell type/tissue/organ specificity. This could bring about distinct clinical consequences, such as embryo lethality or teratogenesis, reproductive dysfunction in the gonads, neurotoxicity of the central nervous system, hyperplasia of the skin, and tumor promotion of initiated tissue. Modulation of GJIC should be viewed as a scientific basis of “epigenetic toxicology” because the alteration of intercellular communication would alter the internal physiological state of the cell. The inhibition of GJIC is a necessary component of mitogenesis (a necessary component of the multistage carcinogenic process). The modulation of GJIC can have both toxicological, as well as therapeutic potential.
Apoptosis and Chemical Carcinogenesis
Authors: Marsman Daniel S. , Barrett J. Carl
Published: May 2006

Long recognized as a normal component of organogenesis during development, apoptosis (programmed cell death) has recently been implicated in alterations of cell growth and differentiation. Tissue homeostasis is normally maintained by a balance between cell division and cell death, with apoptosis often functioning in complement to cell growth. Thus, antithetical parallels in chemical carcinogenesis can be drawn between apoptosis and the proliferative events more commonly addressed. While enhanced cell replication may contribute to an increased frequency of mutation, apoptosis within a tissue may counteract chemical carcinogenesis through loss of mutated cells. Many strong carcinogens act as tumor promoters, selectively expanding an initiated cell population advantageously over surrounding cells. Similarly, chemicals with a selective inhibition of apoptosis within an initiated population would offer a growth advantage. In contrast, chemicals causing selective apoptosis of initiated cells would be expected to have an anticarcinogenic effect. Selective apoptosis, in concert with cell‐specific replication, may explain the unique promoting effects of different carcinogens such as the peroxisome‐proliferating chemicals, phenobarbital, and 2,3,7,8‐tetrachloro‐dibenzo‐p‐dioxin (TCDD). Cell turnover, both cell growth and cell death, is central to the process of chemically induced carcinogenesis in animals and understanding its impact is a critical determinant of the relevance of chemically induced effects to man.
Uncertainty Analysis in Multiplicative Models
Authors: Slob Wout
Published: May 2006

Uncertainties are usually evaluated by Monte Carlo analysis. However, multiplicative models with lognormal uncertainties, which are ubiquitous in risk assessments, allow for a simple and quick analytical uncertainty analysis. The necessary formulae are given, which may be evaluated by a desk calculator. Two examples illustrate the method.
Modeling Fetal Death and Malformation in Developmental Toxicity Studies
Authors: Catalano Paul , Ryan Louise , Scharfstein Daniel
Published: May 2006

We review approaches to dose‐response modeling and risk assessment for binary data from developmental toxicity studies. In particular, we focus on jointly modeling fetal death and malformation and use a continuation ratio formulation of the multinomial distribution to provide a model for risk. Generalized estimating equations are used to account for clustering of animals within litters. The fitted model is then used to calculate doses corresponding to a specified level of excess risk. Two methods of arriving at a lower confidence limit or Benchmark dose are illustrated and compared. We also discuss models based on single binary end points and compare our approach to a binary analysis of whether or not the animal was ‘affected’ (either dead or malformed). The models are illustrated using data from four developmental toxicity studies in EG, DEHP, TGDM, and DYME conducted through the National Toxicology Program.
Assessment of Variability and Uncertainty Distributions for Practical Risk Analyses
Authors: Hattis Dale , Burmaster David E.
Published: May 2006

In recent years the U.S. Environmental Protection Agency has been challenged both externally and internally to move beyond its traditional conservative single‐point treatment of various input parameters in risk assessments. In the first section, we assess when more involved distribution‐based analyses might be indicated for such common types of risk assessment applications as baseline assessments of Superfund sites. Then in two subsequent sections, we give an overview with some case studies of technical analyses of (A) variability/heterogeneity and (B) uncertainty. By “inter‐individual variability” is meant the real variation among individuals in exposure‐producing behavior, in exposures, or some other parameter (such as differences among individual municipal solid waste incinerators in emissions). In contrast, “uncertainty” is a description of the imperfection in knowledge of the true value of a particular parameter or its real variability in an individual or a group. In general uncertainty is reducible by additional information‐gathering or analysis activities (better data, better models), whereas real variability will not change (although it may be more accurately known) as a result of better or more extensive measurements. The purpose of the rather long‐winded exposition of these two final sections is to show the differences between analyses of these two different things, both of which are described using the language of probability distributions.
Potential Negative Impacts of Nuclear Activities on Local Economies: Rethinking the Issue
Authors: Metz William C.
Published: May 2006

Surveys of public opinion about perceptions of risk associated with the nuclear fuel cycle have shown that the public professes a widespread feeling of dread, a fear of associated stigmas, and a concern about possible catastrophic nuclear accidents. Various interest groups and state governments that oppose congressionally mandated siting of centralized high‐level radioactive waste (HLW) storage and disposal facilities are using this negative imagery to create a powerful, emotional obstacle to the siting process. From statistical analyses of images and location preferences, researchers have claimed that possible significant economic losses could potentially accompany the siting of HLW facilities. However, several paradoxes, or self‐contradictory statements, apparently exist between the responses expressed in surveys and the actual economic and demographic behavior evidenced in the marketplace. Federal policymakers need to evaluate whether the request for a change in siting policy is based on subjective fear of a potential negative economic effect or on proven negative effects. Empirically observed behavior does not support predicted negative economic effects based on survey responses.
Communicating Contaminant Risks from Sport‐Caught Fish: The Importance of Target Audience Assessment
Authors: Velicer Christine M. , Knuth Barbara A.
Published: May 2006

A fish consumption health advisory has existed for New York Lake Ontario sport‐caught fish since 1978. Our study objectives were to evaluate the effectiveness of the advisory for reaching potential target audiences and to identify appropriate advisory content, style, and dissemination methods using a risk communication planning model as an evaluation framework. We used a combination of mail surveys and personal interviews with three target audiences (opinion leaders among recreational anglers and charter boat operators, migrant farm workers, and low‐income individuals) and two communicator groups (fishery experts and health care experts). The New York Lake Ontario advisory appeared to be successful in reaching and encouraging risk‐mitigating fish consumption behavior in recreational angler opinion leaders and low‐income individuals but not in migrant farm workers. The advisory may not be reaching two sensitive subpopulations, women of childbearing age and children. Communicators and target audiences differed in their assessments of important information to include in an advisory. The health advisory could be improved with additional information such as risk‐reducing cooking and cleaning methods and by diversifying the dissemination methods to reach the variety of audiences who potentially consume Lake Ontario fish.
Perceived Risk and Uncertainty of Nuclear Waste: Differences Among Science, Business, and Environmental Group Members1
Authors: Jenkins‐Smith Hank , Bassett Gilbert W.
Published: May 2006

This paper presents survey results on perceived risk regarding the management of nuclear waste. Using data taken from random mail surveys of members of scientific, business, and environmental groups in Colorado and New Mexico in the summer of 1990, we examine differences between the groups in their expressed perceptions of risk and also their assessments of the certainty of their beliefs. We consider whether (a) greater uncertainty is associated with greater perceived risks and (b) whether there is greater responsiveness to new information for those whose beliefs are least certain. We find that there are connections between perceived risk and uncertainty, and there is a greater tendency to update risk assessements from a position of greater initial uncertainty. There are, however, differences between the groups as well as asymmetries in their responses to new information. The latter suggests that perceived risks will ratchet upward over time even when information is not biased toward more or less risk.
Fair Processes for Societal Decisions Involving Distributional Inequalities
Authors: Keller L. Robin , Sarin Rakesh K.
Published: May 2006

We investigate fair processes for societal decisions that involve different risks and benefits to different groups. A fair decision‐making process is particularly important for decisions such as siting hazardous facilities. We experimentally evaluate the impact of alternative decision processes on the final choice of hypothetical facility sites and the resulting benefit and risk distribution to groups. The experimental task required choice among many alternative sites for a hazardous facility. Sites differ by the distribution of risks and benefits to each of two communities, and in the attractiveness of the sites to each community. Subjects were divided into three groups: individuals who judged the best site in the role of arbitrators, pairs of negotiators with one person representing each of the two communities, and trios who identified the best site in the role of a siting jury. We found the choices of negotiating and siting jury groups tended to emphasize the communities’preferences compared to the individual arbitrators who tended to focus on balancing the distribution of risks and benefits. Also, undergraduate psychology students, regardless of the dispute resolution mechanism, tended to display more emphasis on the risks and benefits, and graduate business students tended to focus more on the communities’preferences.
Managing the Risk of Global Climate Catastrophe: An Uncertainty Analysis
Authors: Chao Hung‐po
Published: May 2006

Despite much scientific progress over many decades, the nature of global climate change remains highly uncertain, and the possibility of global climate catastrophe is one of the main concerns in public debates about global climate change. In this paper, we present a model which incorporates the risk of climate catastrophe in an analysis of greenhouse gas abatement strategy. In this model, the timing and severity of climate catastrophe are treated probabilistically. The impacts of key uncertainties on optimal policy are analyzed, and the expected values of additional information that reduces the uncertainty associated with the world economy, carbon cycle, climate change, and climate damage are estimated.
Putting the First Audience First: Conducting Useful Evaluation for a Risk‐Related Government Agency
Authors: Balch George I. , Sutton Sharyn M.
Published: May 2006

The risk communication practitioner in a government agency has two essential, interdependent tasks. One is to help develop and monitor effective communication programs with various external public audiences. The other task is to do the same thing for the senior government managers whose support is a prerequisite to addressing the first audience. Hence, the second audience–the manager–is really the first. This paper addresses ways in which communication practitioners can satisfy this crucial audience. A profile of these managers suggests that they would find it highly beneficial to have more control over the public problems they encounter, especially in view of the growing pressures to do more with less and demonstrate “customer satisfaction.” They would rather avoid crises than manage them. And they would rather have their bosses praise their successes than challenge their budgets or punish their perceived difficulties or failures. Communication practitioners who can help them attain such benefits will find their efforts in great demand. They would be helpful team members who provide timely insights that can make and show agency success. We offer ten ways for communication practitioners to be more useful which focus their current strengths on satisfying senior managers’needs by becoming more valuable members of the program team. By becoming more useful to the senior manager they serve both the agency and its publics.
Improvement of Highway Safety I: Identification of Causal Factors Through Fault‐Tree Modeling1
Authors: Kuzminski P. , Eisele J. S. , Garber N. , Schwing R. , Haimes Y. Y. , Li D. , Chowdhury M.
Published: May 2006

As the first article of a two‐part series, the purpose of this paper is to examine the functional factors that contribute to automobile accident occurrence and to model the causation structure in the form of a fault‐tree. The fault‐tree model provides an intuitive framework for qualitatively decomposing possible pathways to accident occurrence. Fault‐tree analysis also provides a statistical representation of how interacting driver, vehicle, and environmental factors contribute to the likelihood of automobile accident occurrence. The application of this model facilitates pinpointing those factors that most contribute to accident causation and subsequently enables the identification and comparison of potential crash avoidance technologies.
Five‐Hundred Life‐Saving Interventions and Their Cost‐Effectiveness
Authors: Tengs Tammy O. , Adams Miriam E. , Pliskin Joseph S. , Safran Dana Gelb , Siegel Joanna E. , Weinstein Milton C. , Graham John D.
Published: May 2006

We gathered information on the cost‐effectiveness of life‐saving interventions in the United States from publicly available economic analyses. “Life‐saving interventions” were defined as any behavioral and/or technological strategy that reduces the probability of premature death among a specified target population. We defined cost‐effectiveness as the net resource costs of an intervention per year of life saved. To improve the comparability of cost‐effectiveness ratios arrived at with diverse methods, we established fixed definitional goals and revised published estimates, when necessary and feasible, to meet these goals. The 587 interventions identified ranged from those that save more resources than they cost, to those costing more than 10 billion dollars per year of life saved. Overall, the median intervention costs $42,000 per life‐year saved. The median medical intervention costs $19,000/life‐year; injury reduction $48,000/life‐year; and toxin control $2,800,000/life‐year. Cost/life‐year ratios and bibliographic references for more than 500 life‐saving interventions are provided.
Effects of Organizational Environment, Internal Structure, and Team Climate on the Effectiveness of Local Emergency Planning Committees1
Authors: Lindell Michael K. , Whitney David J.
Published: May 2006

This study proposed and tested a model of factors influencing the effectiveness of Local Emergency Planning Committees (LEPCs). Data were collected from the chairs of Michigan LEPCs, who were asked to provide information about their LEPCs’staffing, activities, resources, and team climate, as well as information about community hazards and relationships with other organizations in their communities. The model was partially supported. As hypothesized, team climate substantially mediated the relationships between an LEPCs effectiveness and many of the attributes of its internal structure and external environment. In addition, three (emergency planning resources, community support and LEPC staffing and structure) out of four categories of variables hypothesized to influence team climate were, in fact directly related to it. There were two major inconsistencies with the model. First, two types of emergency planning resources were found to have a direct influence on LEPC effectiveness rather than an indirect effect mediated by team climate. In addition, hazard vulnerability was hypothesized to have a direct effect on team climate, but the data showed this relationship was mediated by community support and by LEPC staffing and structure. A revised model was proposed that suggests ways in which members can change the structure of an LEPC and strategies to enhance its effectiveness.
Presenting Uncertainty in Health Risk Assessment: Initial Studies of Its Effects on Risk Perception and Trust
Authors: Johnson Branden B. , Slovic Paul
Published: May 2006

Some analysts suggest that discussing uncertainties in health risk assessments might reduce citizens’perceptions of risk and increase their respect for the risk‐assessing agency. We tested this assumption with simulated news stories varying simple displays of uncertainty (e.g., a range of risk estimates, with and without graphics). Subjects from Eugene, Oregon, read one story each, and then answered a questionnaire. Three studies tested between 180 and 272 subjects each. Two focus groups obtained more detailed responses to these stories. The results suggested that (1) people are unfamiliar with uncertainty in risk assessments and in science; (2) people may recognize uncertainty when it is presented simply; (3) graphics may help people recognize uncertainty; (4) reactions to the environmental problems in the stories seemed affected less by presentation of uncertainty than by general risk attitudes and perceptions; (5) agency discussion of uncertainty in risk estimates may signal agency honesty and agency incompetence for some people; and (6) people seem to see lower risk estimates (10‐6, as opposed to 10‐3) as less credible. These findings, if confirmed, would have important implications for risk communication.
On the MVK Stochastic Carcinogenesis Model with Erlang Distributed Cell Life Lengths
Authors: Zheng Qi
Published: May 2006

This paper proposes extending the MVK carcinogenesis model by adopting the Erlang distribution for the life length of the intermediate cells. The investigation concentrates on the survival function and the mean value functions. The approach is basically numerical, making use of the Mathematica software system. The paper also provides a closed form expression for the survival function for a variation of the original MVK model, where all the model parameters are piecewise constants.
Implications of Developmental Toxicity Study Design for Quantitative Risk Assessment
Authors: Weller Edie A. , Catalano Paul J. , Williams Paige L.
Published: May 2006

Standard experimental designs for conducting developmental toxicity studies typically include three‐ or four‐dose levels in addition to a control group. Some researchers have suggested that designs with more exposure groups would improve dose‐response characterization and risk estimation. Such proposals have not, however, been supported by the results of simulation studies, which instead back the use of fewer dose levels. This discrepancy is partly due to using a known dose–response pattern to generate data, making model choice obvious. While the carcinogenicity literature has explored implications of different study designs, little attention has been given to the role of design in developmental toxicity risk assessment (or noncancer toxicology in general). In this research, we explore the implications of various experimental designs for developmental toxicity by resampling data from a large study of 2,4,5‐trichlorophenoxyacetic acid in mice. We compare the properties of benchmark dose (BMD) estimation for different design strategies by randomly selecting animals within particular dose groups from the entire 2,4,5‐T database of over 77,000 birth outcomes to create smaller “pseudo‐studies” that are representative of standard bioassay sample sizes. Our results show that experimental designs which include more dose levels have advantages in terms of risk characterization and estimation.
Characterizing Perception of Ecological Risk
Authors: McDaniels Timothy , Axelrod Lawrence J. , Slovic Paul
Published: May 2006

Relatively little attention has been paid to the role of human perception and judgment in ecological risk management. This paper attempts to characterize perceived ecological risk, using the psychometric paradigm developed in the domain of human health risk perception. The research began by eliciting a set of scale characteristics and risk items (e.g., technologies, actions, events, beliefs) from focus group participants. Participants in the main study were 68 university students who completed a survey instrument that elicited ratings for each of 65 items on 30 characteristic scales and one scale regarding general risk to natural environments. The results are presented in terms of mean responses over individuals for each scale and item combination. Factor analyses show that five factors characterize the judgment data. These have been termed: impact on species, human benefits, impact on humans, avoidability, and knowledge of impacts. The factor results correspond with initial expectations and provide a plausible characterization of judgments regarding ecological risk. Some comparisons of mean responses for selected individual items are also presented.
Direct Inference, Probability, and a Conceptual Gulf in Risk Communication
Authors: Walker Vern R.
Published: May 2006

Differences in the conceptual frameworks of scientists and nonscientists may create barriers to risk communication. This article examines two such conceptual problems. First, the logic of “direct inference” from group statistics to probabilities about specific individuals suggests that individuals might be acting rationally in refusing to apply to themselves the conclusions of regulatory risk assessments. Second, while regulators and risk assessment scientists often use an “objectivist” or “relative frequency” interpretation of probability statements, members of the public are more likely to adopt a “subjectivist” or “degree of confidence” interpretation when estimating their personal risks, and either misunderstand or significantly discount the relevance of risk assessment conclusions. If these analyses of inference and probability are correct, there may be a conceptual gulf at the center of risk communication that cannot be bridged by additional data about the magnitude of group risk. Suggestions are made for empirical studies that might help regulators deal with this conceptual gulf.
Policy Goals for Health and Safety
Authors: Lind Niels C.
Published: May 2006

Health management and safety regulation are separate disciplines but share the aim to extend expectancy of life in good health. The need to improve cost‐effectiveness calls for their co‐ordinated management according to a unified rationale. Three guiding principles of accountability, demonstrable net benefit and a uniform measure of performance, have been laid out in Canada by the Joint Committee on Health and Safety. They call for open accounting in terms of (health‐related quality‐adjusted) life expectancy. The principles are utilitarian in format but, it is argued, inequity is naturally diminished in the process of optimizing cost‐effectiveness through maximum marginal returns. Comments are made on practical implementation. The need for public consent in practice calls for two additional principles reflecting fair procedure and sovereignty of the citizens. It is concluded that public health and safety measures should be surveyed, documented for cost‐effectiveness and prioritized for improvement.
Perspectives on Risk Management
Authors: Somers Emmanuel
Published: May 2006

The development of the techniques of risk assessment and management are considered, noting the early emphasis on quantitative approaches. The basic strategies available to governments for risk management—educational, economic, and regulatory—are discussed. Six specific issues are considered with reference to the Canadian experience and the lessons learned. These are: the separation of risk assessment from risk management; the uncertainties of science; the weakness of numerical comparisons; too great a trust in education; the Great White Father Syndrome; and regulatory perils. This examination shows a number of inadequacies in the application of risk management techniques. It is suggested that knowledge of the limitations of quantitative assessment in its application to decision‐making together with the involvement of those affected by the risk in the decision‐making processes will lead to greater success.