Showing papers in "Risk Analysis in 1989"

Perceived Risk, Stigma, and Potential Economic Impacts of a High‐Level Nuclear Waste Repository in Nevada

Abstract: This study investigates the potential impacts of the proposed nuclear waste repository at Yucca Mountain, Nevada, upon tourism, retirement and job-related migration, and business development in Las Vegas and the state. Adverse impacts may be expected to result from perceptions of risk, stigmatization, and socially amplified reactions to "unfortunate events" associated with the repository (major and minor accidents, discoveries of radiation releases, evidence of mismanagement, attempts to sabotage or disrupt the facility, etc.). The conceptual underpinnings of risk perception, stigmatization, and social amplification are discussed and empirical data are presented to demonstrate how nuclear images associated with Las Vegas and the State of Nevada might trigger adverse economic effects. The possibility that intense negative imagery associated with the repository may cause significant harm to Nevada's economy can no longer be ignored by serious attempts to assess the risks and impacts of this unique facility. The behavioral processes described here appear relevant as well to the social impact assessment of any proposed facility that produces, uses, transports, or disposes of hazardous materials.

Dimensions of Risk

Abstract: Eight major factors of risk comparisons are presented, and the conventional reduction of the risk concept to a unidimensional format is challenged. The similarities between risk issues and other issues of the social decision process are stressed. It is concluded that risk decisions are part of the general political process, and cannot be isolated from this. Expert assessments should be presented in a way that reflects the complexity of the subject matter, instead of repressing it.

Technical and Democratic Values in Risk Analysis1

Abstract: Summary So, we can argue that the lay public are not fools in their attitudes about risk. That nonexperts should show more concern over hazardous waste facilities in their neighborhoods than radon levels in their homes is not a sign of irrationality (because aggregate and individual risks are greater from the radon), but simply a sign that nonexperts are working from a different set of criteria. These criteria are incorporated in what I call the democratic model. The democratic model evaluates risk based on its social and political consequences, such as possible disruption in the social fabric or a loss of communality. Lay criteria for assessing the impact of risk decisions are not explicit, like the those of the risk analyst, but are embedded in cultural values. Similarly, lay evaluations of risk incorporate substantive and procedural democratic values, such as the acceptability of processes for making decisions, the ethics of the distribution of risk, and the capacity to control a source of risk in the community's interests. Finally, the democratic model relates judgments about risks to the competence (Can we trust them?) and the legitimacy (Should we trust them?) of the social institutions that impose and control those risks. The public's judgments about risk are not inferior, but different, and arguably richer than those of the experts.

Public Perceptions of the Risks and Benefits of Technology1

Abstract: This study attempted to verify and extend previous research on people's perceptions of the risks and benefits of technology and their judgments concerning the acceptability of technology safety regulations. The study addressed several limitations of prior work, in that: (1) it was the first “expressed-preference” study to collect data from large, representative samples of Americans; (2) the research design made “person,” rather than “technology,” the unit of statistical analysis; and (3) the study employed an expanded set of independent variables, including three qualitative benefit characteristics. The results confirmed several major conclusions of prior expressed-preference research, the most important being that members of the public tend to define “risks,”“benefits,” and “acceptability” in a complex, multidimensional manner; and that their definitions differ significantly from those used by professional risk-managers and other technical experts in quantitative assessments of risk and acceptability. The results also indicated that people's stances toward technology regulation tend to cut across traditional sociodemographic lines.

A Stochastic Two‐Stage Model for Cancer Risk Assessment. II. The Number and Size of Premalignant Clones

Abstract: Mathematical expressions are derived, under different dosing patterns, for the number and size of premalignant clones within the framework of a two-mutation model for carcinogenesis, which has previously been shown to be consistent with a large body of epidemiologic and experimental data.

Risk Perceptions of Hong Kongese vs. Americans

Abstract: Hong Kong students rated the risk of 30 hazards and quantified a subset on six risk characteristics; data are compared to a prior study of American students. Hong Kongese rated 10 hazards substantially higher and five hazards substantially lower than Americans, and factor structures indicated differences on five hazards. Possible explanations for these differences are discussed.

Risk Perception and Social Acceptability of Technologies: The French Case

Abstract: The authors present results of a February 1987 survey on judged frequency of mortality causes and risk perception of technologies in a representative sample of the French population. Although the French context is very different, and the impact of public controversies have been very limited on technological choices such as the nuclear energy program, strong similarities in risk perception of technologies are observed with results from U.S. surveys. Results, which could be worthwhile for other countries, suggest that risk perception is influenced by two different types of components. The first influence is the global feeling of “security” that society procures to its members. Such feeling depends on the individual's socioeconomic status, subjective state of health, and personal discomfort in daily life, and explains individual aversion to risk independently of the mortality causes or technologies involved. The second influence is the degree of perceived social legitimization of the activities involving risks. Risks of medical and transportation activities are strongly opposed to illegitimate risky behaviors (smoking, drugs, alcohol); technologies which have been an object of public debate (nuclear plants, the chemical industry, lead in gasoline) have an intermediate position reflecting the remaining uncertainties of public opinion about their risk–benefit balancing. Tentative conclusions for risk communication are proposed.

A dose-response analysis of skin cancer from inorganic arsenic in drinking water.

Abstract: A study of the prevalence of skin cancer among 40,421 persons consuming arsenic-contaminated drinking water in Taiwan was used for a cancer dose-response assessment of ingested arsenic. The numbers of persons at risk over three dose intervals and four exposure durations were estimated from the data in order to apply the method of maximum likelihood to a multistage-Weibull time/dose-response model. A constant exposure level since birth for each of the exposure categories was assumed. It was found that the cumulative hazard increases as a power of three in age, and is linear or quadratic (with a linear coefficient) in dose. Observations from a smaller epidemiologic survey in Mexico were similar to what would be predicted from the model of the Taiwan data. Assuming that the skin cancer risk from ingested arsenic in the American population would also be similar to the Taiwan population, an American male would have a lifetime risk of developing skin cancer of 1.3 x 10(-3) (3.0 x 10(-3)) if exposed to 1 microgram/kg/day for a 76-year lifespan (median lifespan in the U.S.).

Network Evening News Coverage of Environmental Risk

Abstract: ABC, CBS, and NBC's carefully crafted and expensively produced evening news broadcasts devoted 1.7% of their air time to 564 stories about man-made environmental risks during the period from January 1984 to February 1986. Little relationship was found between amount of coverage and public health risk. Instead, the networks appeared to be using traditional journalistic determinants of news (timeliness, proximity, prominence, consequence, and human interest) plus the broadcast criterion of visual impact to determine the degree of coverage of risk issues. Government, industry, and citizens accounted for two-thirds of the sources cited by the networks. Experts and spokespersons for environmental advocacy groups were sparsely used as sources. Given the media's need for news pegs, acute and chronic risk stories were covered differently. Acute risk stories were reported in a clearly defined cycle, peaking on the second day with on-the-scene reports and film-clips of devastation. In keeping with a decrease in visual drama, later reports were shorter and emphasized legal and political considerations. Chronic risk coverage followed the release of new scientific, legal, or political information.

The Decline of Deference: The Political Context of Risk Communication

Abstract: Risk communication is seen as an important adjunct to the process of siting locally noxious facilities. To understand how risk communication might function in such a process, one needs to understand the political context that gives rise to public opposition to such facilities in the first place. This analysis draws on a variety of data to describe the decline of deference, a situation in which a hostile and alienated public is mobilized primarily through ad hoc voluntary organizations, and is increasingly reluctant to defer important decisions to institutional elites. Risk communication programs must be designed to offset the trends that result in the decline of deference. This conclusion differs markedly from the conventional wisdom that risk communication is merely a device for providing information to citizens so sthat they may make more rational decisions.

Decision‐Making, Time Horizons, and Risk in the Very Long‐Term Perspective

Abstract: Some decisions made today have far-reaching consequences as exemplified by those concerning nuclear power and spent nuclear fuel. The investigation presented here uses a decision theoretic framework in which time horizons and the discounting of negative consequences play significant roles. The results indicated wide variations in the lengths of the planning horizons judged to be adequate not only across a number of activities, including nuclear waste management, but also across groups of subjects (e.g., engineering students, retired people, and nuclear fuel experts). The paper reports typical judgments and correlations between different variables for different groups of subjects. The differences across groups reflect potential sources of conflict, depending in part on different values and different perceptions of more or less uncertain facts. Discounting functions for negative consequences in the future were also established. A range in differences in the speed of discounting were found and illustrated. Furthermore, it was found that substantial proportions in all groups regarded negative consequences related to nuclear waste as nondiscountable. When asked about the effect of time until outcome on acceptable probability of a negative outcome, many subjects used the probability concept in an incoherent way, illustrating the great difficulty in communicating small probabilities in a long-term risk context.

Setting a Context for Explaining Risk

Abstract: Agency representatives often believe that if they could only find ways to explain risk data more clearly, communities would accept risk that scientists see as minimal, and take seriously risks scientists see as serious. While explaining the data effectively is important, agencies and industries need to place a greater priority on understanding community concerns, involving communities in risk decisions, and developing trust and credibility.

Are large differences in "lifesaving" costs justified? A psychometric study of the relative value placed on preventing deaths.

Abstract: Government actions to reduce risks to health have varied greatly in their cost per death prevented, frequently by 10-fold or even 100-fold. This research asks whether disparities of this magnitude are justified by citizens' preferences abut the relative value of reducing deaths from different hazards. Four samples were asked to rank the relative priority of preventing deaths through 8 realistic programs, each addressed to a different hazard, and then to rate how large the differences in spending should be. Subjects were not asked to give absolute values on preventing deaths and were asked only for their relative valuation of the benefits of preventing a death, not to weigh the benefits and costs or to determine an optimal spending level. We found that in all samples the median respondent valued his top-rated program 5 to 6 times more than his bottom-rated program. However, because individuals disagreed upon the relative priority for different programs, the aggregated rankings barely showed more than a 2-fold difference in the amounts that should be spent. Thus, for the important programs considered by these samples, a large variation in spending does not appear to be justified on the basis of differentials in the values placed on preventing different types of deaths. A more deliberative methodology like the one used here appears fruitful for providing insights to policymakers about preferences in this sensitive area.

Interspecies Conversion of Kinetically Equivalent Doses1

Abstract: A framework is presented within which to organize consideration of appropriate measures of delivered dose and selection of an appropriate procedure for interspecies conversion of kinetically equivalent doses. Systematic species dependencies of simple kinetic relationships between administered and delivered dose are developed. Interspecies scaling of kinetic parameters, including firstorder rate constants and maximum rates of capacity-limited processes, is discussed, and the effects of conventional scaling procedures on initial and steady-state concentrations and on areas under the blood concentration curve are shown. Particular attention is given to production of reactive metabolites. It is shown that interspecies dose or dose rate conversion on the basis of the 3/4 power of body weight is consistently either realistic or conservative when the conversion is carried out from smaller to larger species, except when first-order elimination and capacity-limited production of an active metabolite coexist. In this case, the 3/4 power of body weight conversion procedure may be either overpredictive or underpredictive, depending on the relative dependence of the efficiency of metabolite production and elimination on species body weight. Interspecies dose conversion on a direct mg/kg body weight basis is consistently much less conservative than the 3/4 power of body weight procedure, resulting when scaling from smaller to larger species in underestimation of delivered dose or of steady-state concentration of both parent and metabolite for all of the kinetic relationships considered. Applicability and limitations of these procedures are also discussed.

The Health Risks of Energy Production

Abstract: Any personal or societal activity, besides bringing us benefits, also carries some risk Energy production and use are no exceptions In order to judge these risks, they must be quantified, and the risks of all alternative methods of producing this energy must then be compared among each other These risks originate in many parts of the energy cycle; they are diverse in character and involve different parts of the population It is therefore necessary to discriminate between many aspects of risk so that only reasonably comparable categories are compared The results of a critical analysis of the international risk literature are presented, which are applicable to power production plants as they could be built today in central European countries This review pays special attention to the possibility of severe accidents occurring, which attract so much attention in our modern societies It turns out that the health risks of routine nuclear energy production are lower than the risks of other energy options, particularly for the general public The probability of a severe accident occurring is far higher for all conventional energy options Only the renewable systems utilizing the energy of the sun and the wind are not susceptible to severe accidents

The Role of Actuaries and Underwriters in Insuring Ambiguous Risks

Abstract: Although there is a large body of literature on the unwillingness of the insurance industry to offer protection against risks such as environmental pollution, there has been only limited analysis regarding two key actors in the decision process—actuaries and underwriters. However, if actuaries and underwriters feel that a particular type of risk is uninsurable, then it is unlikely to be offered. This paper investigates how ambiguities associated with a risk affect actuary and underwriter decision processes, the paper contends that the decision of the insurance industry to not provide protection against environmental pollution liability is due to ambiguity of the risk. Empirical evidence from controlled laboratory experiments with actuaries and a model of choice in underwriter decision processes support this point.

Multistage modeling of lung cancer mortality among arsenic-exposed copper-smelter workers.

Abstract: Multistage modeling incorporating a time-dependent exposure pattern is applied to lung cancer mortality data obtained from a cohort of 2802 arsenic-exposed copper-smelter workers who worked 1 or more years during the period 1940–1964 at a copper smelter at Tacoma, Washington. The workers were followed for death through 1976. There were 100 deaths due to lung cancer during the follow-up period. Exposures to air arsenic levels measured in μ/m3 were estimated from departmental air arsenic and workers urinary arsenic measurements. Relationships of different temporal variables with excess death rates are examined to judge qualitatively the implications of the multistage cancer process. Analysis to date indicates a late stage effect of arsenic although an additional early stage effect cannot be ruled out.

A risk assessment for selected lead-induced health effects: an example of a general methodology.

Abstract: The research described here is part of a larger risk assessment project to aid the U.S. Environmental Protection Agency (EPA) in its review of the primary National Ambient Air Quality Standard for lead. The methodology can be applied to many situations in which a policy decision about a toxic substance is required in the face of incomplete data. Numerical results are presented for three potentially adverse lead-induced effects of interest to EPA: elevated erythrocyte protoporphyrin (EP), hemoglobin (Hb) decrement, and intelligence quotient (IQ) decrement.

Major Hazard Information Policy in the European Community: Implications for Risk Analysis

Abstract: The main impetus to the development of information about major industrial hazards in the European Community comes from the so-called Seveso Directive, which defines an information network and requires the generation and transmission of information as the basis for accident prevention and risk management. This important policy development, which calls for the formal identification and analysis of major hazards and the communication of risk information to members of the public, presents new opportunities and challenges to risk analysis and research in Europe. This paper briefly reviews the accidents that gave rise to the Directive and shaped its content, and then summarizes its requirements. The status of its implementation in the EC Member States is discussed, with special emphasis given to the comparison of safety analysis practices, the Major Accident Reporting System (MARS), and risk communication. Some new research directions stimulated by the Directive are identified.

Estimating the risks of smoking, air pollution, and passive smoke on acute respiratory conditions

Abstract: Five years of the annual Health Interview Survey, conducted by the National Center for Health Statistics, are used to estimate the effects of air pollution, smoking, and environmental tobacco smoke on respiratory restrictions in activity for adults, and bed disability for children. After adjusting for several socioeconomic factors, the multiple regression estimates indicate that an independent and statistically significant association exists between these three forms of air pollution and respiratory morbidity. The comparative risks of these exposures are computed and the plausibility of the relative risks is examined by comparing the equivalent doses with actual measurements of exposure taken in the homes of smokers. The results indicate that: (1) smokers will have a 55-75% excess in days with respiratory conditions severe enough to cause reductions in normal activity; (2) a 1 microgram increase in fine particulate matter air pollution is associated with a 3% excess in acute respiratory disease; and (3) a pack-a-day smoker will increase respiratory restricted days for a nonsmoking spouse by 20% and increase the number of bed disability days for young children living in the household by 20%. The results also indicate that the estimates of the effects of secondhand smoking on children are improved whenmore » the mother's work status is known and incorporated into the exposure estimate.« less

Informing the Public About Uncertain Risks

Abstract: Many problems arise in connection with the communication of risk information. In this article the content of the information communicated is taken as a starting-point for analyzing the risk communication process. We studied the way in which authorities communicated health risks to local residents in Dutch soil pollution situations and found that communication problems were characterized more by misunderstanding and conflict between parties with different views and interests than by a lack of understanding. Therefore, it is important to look more closely at the way the communicators of information (in our cases, officials) select risk information from risk assessments, and to study the effects that the information selected has on the receivers (in our cases, residents). Both the process of selection by the officials and the process of interpretation by the residents will be shown to be influenced by the different institutional backgrounds. The article presents a new approach to risk communication. Both the risk information presented by the authorities and the public reactions to this risk information are considered to reflect the institutional background of authorities and residents, and can be analyzed in these terms. Such an approach has consequences for the study of risk communication and the manner in which it is practiced.

Additive and Multiplicative Models and Multistage Carcinogenesis Theory

Abstract: In light of the Armitage-Doll multistage carcinogenesis theory, this paper examines the assumption that an additive relative risk relationship is indicative of two carcinogens that affect the same stage in the cancer process. We present formulas to compute excess cancer risks for a variety of patterns for limited exposure durations to two carcinogens that affect the first and penultimate stages; and using an index of synergy proposed by Thomas (1982), we find a number of these patterns to produce additive, or nearly additive, relative risk relationships. The consistent feature of these patterns is that the two exposure periods are of short duration and occur close together.

A perspective on dioxin emissions from municipal solid waste incinerators.

Abstract: This paper discusses the following key issues concerning human exposure to dioxins and furans emitted from typical, modern MSW incinerators: (1) Are MSW incinerators the major source of PCDD/PCDF input into the environment? (2) Are environmental concentrations around MSW incinerators substantially elevated relative to background levels? And (3) are MSW incinerators the major source of human exposure to PCDDs and PCDFs? Current scientific evidence indicates that (1) combustion sources in general (including steel mills, copper smelting plants, motor vehicles, pulp and paper mills, and MSW incinerators) are major sources of PCDD/PCDF input in the environment; (2) environmental concentrations of PCDDs and PCDFs around operating MSW incinerators are not substantially elevated; and (3) 99% of human exposure to PCDDs and PCDFs is from background contamination, even for individuals living near a modern MSW incinerator.

Conventional Wisdom on Risk Communication and Evidence from a Field Experiment

Abstract: A recent comprehensive review of the literature identified a number of facts and principles governing risk communication. This paper evaluates several of these propositions using recent evidence from a field experiment in communicating the risks from radon in homes. At this point in the research, data relate primarily to the response of risk perceptions to different information treatments and different personal characteristics. The effect of various causal factors is sensitive to the particular test of risk perception applied. No information treatment was clearly superior for all tasks. An important implication of these findings is that risk communicators must determine what specific task or tasks the information program should enable people to do.

Traffic Accidents and Convictions: Group Totals Versus Rate per Kilometer Driven

Abstract: Using group totals, young drivers, male drivers, and especially young male drivers are substantially over-represented in terms of both traffic accidents and traffic-related convictions. On the other hand, when accidents and convictions are considered in terms of their rates while the person is actually driving, older drivers and female drivers gain in importance, with the female drivers' traffic accident rate and rates for some convictions exceeding the male drivers' rates. Similarly, the older drivers' accident rate and rates on some convictions exceeded the younger drivers' rates when considered in terms of driving exposure. In addition, these findings lead one to speculate that recent driving exposure more than driver age is the central factor in traffic accident involvement. The implications for policy makers and educators are clear. Although young male drivers are undeniably a legitimate focus for traffic accident countermeasures, they should not be targeted at the expense of drivers who drive less but have as high or higher accident rates—female and older drivers.