ALBERT

Notes: Periodically, ethical objections are raised against the practice of discounting for future effects. Concerns about the potential effects on future generations from long-term nuclear waste disposal and global climate change have caused these ethical objections to recur. This article rebuts the various ethical objections to future discounting on practical, ethical, and analytic grounds. Discounting for future effects is a ubiquitous practice that cannot be practically prevented. In the event that public policy would dictate against future discounting in public decisions, such a constraint could never be successfully imposed on markets. Market values will always reflect the full, discounted streams of future effects even if governments prohibited the practice among individuals. Ethically, there is no basis for choosing an upper-bound time horizon beyond which discounting should be rejected. Any proposed horizon is arbitrary and has no obvious foundation. All decisions are fundamentally irreversible, so opponents of future discounting also must define a degree of irreversibility beyond which normal discounting should not apply, and defend on ethical grounds the basis for this demarcation. This task is further complicated by the likelihood that choices are rarely, if ever, as irreversible as opponents suggest. Typical examples given to prove future discounting is inappropriate overstate the degree of irreversibility actually present and understate subsequent opportunities for modifications. Finally, opposition to distant-future discounting on the ground that burdens are shifted to future generations must face the fact that such shifts are characteristic of intergenerational transfers now practiced widely and with great public support.

Notes: Like radioactive waste, municipal solid waste (MSW) requires consideration of a complex mix of intergenerational and intragenerational risks surrounded by uncertain science. Unlike radioactive waste, MSW is a common problem and hence one often perceived to be controllable, at least until a required facility is proposed in a particular community. The intragenerational risks focused on local communities rouse intense public pressures for management. Although some of the risks can be quantified, the risk assessment process cannot deal with all questions. This article examines the multiple dimensions of the decisions required to be made and the weaknesses of a number of decision tools traditionally used. A case is made for the need to integrate decision tools appropriate to the risks into reflexive and iterative decision processes open to public involvement. It is argued that this presents the best hope of both optimizing decisions about the intragenerational risks as well as raising public debate about the importance of sustainable waste management in transgenerational terms.

Notes: Late in the 1998 hurricane season, Central America was slammed by a devastating hurricane. Honduras, Nicaragua, El Salvador, Guatemala, and Belize were greatly impacted by Hurricane Mitch, one of the deadliest storms to affect the region in the past 200 years. The economies of each of these countries were badly affected. In the case of Honduras — at the time the fourth-poorest country in Latin America — its president suggested that 50 years of progress had been wiped out by the floods and mudslides associated with this relatively short-lived storm system. Humanitarian assistance poured into the region in the first months following the disaster. As of mid-2000, various national, bilateral, international, and nongovernmental programs were in progress or on the drawing board for recovery, reconstruction, and renewed development of the worst affected countries. Using Honduras as a case study, some of the ethical issues that abound in the decisions of whom to help, when, and how to help them in the wake of such an extreme climate-related human tragedy are examined. Should development assistance be focused on those who have been directly and adversely affected by this storm, or should the emphasis be on reducing the risk of exposure by future generations to such disasters? Is there yet another approach that seeks to protect future generations from similar harm while at the same time assisting present-day victims to get through their hardships?

Notes: This article focuses on aspects of intragenerational and intergenerational equity in the context of a unique policy experiment: the effort of the U.S. government to site a monitored, retrievable storage (MRS) facility for high-level civilian nuclear waste. This process and its outcomes are examined from both normative and subjective perspectives. While the MRS siting process was designed to be equitable, its eventual focus on Native American communities raises profound questions about environmental justice, as well as procedural, outcome, and intergenerational equity in cross-cultural contexts. The diverse reactions among Native American tribes demonstrate that translating theoretical concepts of equity into practice is an extraordinarily complex exercise. The MRS siting process, instead of being a bold policy experiment that promoted equity, emerges substantially flawed after its implementation in the Native American context.

Notes: The Food Quality Protection Act and the 1996 amendments to the Safe Drinking Water Act are two of the most recent examples of legislation calling for protection of susceptible subpopulations. As regulatory deadlines draw nearer, controversies in scientific and policy arenas increase about incorporating susceptibility in risk assessment. The previously accepted working definition of “susceptibility” has already been called into question. Part of the controversy results from different disciplines conceiving of susceptibility in different ways. Understanding the conceptual differences embodied within definitions can provide a basis on which a revised working definition may be developed across disciplines. The purposes of this article are to describe the varying definitions of susceptibility, discuss the differing concepts incorporated in the definitions, and recommend ways in which susceptibility may be defined and framed to meet current risk assessment needs. The present analysis of definitions from the fields of ecology, biology, engineering, medicine, epidemiology, and toxicology revealed different emphases that relate to the underlying perspectives and methods of each field. It is likely that susceptibility will need to be formally defined for public policy purposes, but until that time, the use of more informal communication and decision-making processes is suggested to develop and utilize a new working consensus on the definition of susceptibility.

Notes: This study evaluates airborne concentrations of common trihalomethane (THM) compounds in bathrooms during showering and bathing in homes supplied with chlorinated tap water. Three homes in an urban area were selected, each having three bedrooms, a full bath, and approximately 1,000 square feet of living area. THMs were concurrently measured in tap water and air in the shower/bath enclosure and the bathroom vanity area using Summa canisters. Chloroform (TCM), bromodichloromethane (BDCM), and chlorodibromomethane (CDBM) were quantified using U.S. Environmental Protection Agency (EPA) Method TO-14. Air samples were collected prior to, during, and after the water-use event for 16 shower and 7 bath events. Flow rate and temperature were measured, but not controlled. The increase in average airborne concentration (± standard error) during showers (expressed as μg/m3 in shower enclosure or bathroom air per μg/L in water) was 3.3 ± 0.4 for TCM, 1.8 ± 0.3 for BDCM, and 0.5 ± 0.1 for CDBM (n = 12), and during baths was 1.2 ± 0.4 for TCM, 0.59 ± 0.21 for BDCM, and 0.15 ± 0.05 for CDBM (n = 4). The relative contribution of each chemical to the airborne concentrations was consistent for all shower and bath events, with apparent release of TCM〉 CDBM. The results are therefore consistent with their relative concentration in tap water and their vapor pressures. When the shower findings for TCM are normalized for water concentration, flow rate, shower volume, and duration, the average exposure concentrations in these urban residences are about 30% lower than those reported by other investigators using EPA analytical methods. This difference is likely attributable primarily to greater air exchange rates in residential shower/bath stalls compared to more “airtight” laboratory shower chambers. This appears to be the first field study to thoroughly evaluate THM exposures from residential showers and baths, and can be used to validate previously published models of tap water volatile chemical transfer to indoor air.

Notes: This article explores public perceptions of, and attitudes toward, possible health risks from polluted coastal bathing waters in the United Kingdom. Cultural theory is applied in the present analysis, using a mixed methodology of quantitative analysis from interviews and qualitative interpretation of focus group discussions to provide insights into how different cultural solidarities view a number of issues. These include risks to health; attitudes toward regulation; public consultation and information provision; and trust, blame, and accountability applied to different stakeholders in the bathing-water-quality debate. The results show that individuals' standpoints can be represented on a number of dimensions, consistent with cultural theory, including perceptions of power and authority, beliefs in the efficacy of collective action, and acceptance or rejection of incremental change as opposed to radical solutions. The discussion focuses both on methodological and substantive issues related to the use of cultural theory as a research tool, and on policy recommendations arising from this research.

Notes: Social theories of risk suggest that a combination of scientific and cultural perspectives converge to influence risk perception. This article first surveys sociological perspectives suggesting that risks from modern technological development have become predominant concerns in the social consciousness. Particular attention is given to those theses describing how social elements work to create perception of risks in relation to new technologies. The themes that emerge from this survey are then related to comtemporary debates concerning biotechnology. Specific attention is given to recent controversies regarding genetically modified crops, and parallels are drawn between debates over nuclear power and biotechnology. A procedural ethic for public discourse and decision making over the diffusion of genetically modified foods is offered. Ethical and social theories are linked with the hope that by recognizing the social dimensions of debates over new technologies a broader framework for conducting risk analysis may emerge.

Notes: A risk assessment was performed to incorporate uncertainty in food processing conditions to develop a risk-based sterilization process design. The focus of this analysis was uncertainty associated with heterogeneous food products. Quartered button mushrooms were the chosen food product because it represents the most typical type. A model for sterilization of spherical particles was utilized, and each parameter's uncertainty was characterized for use under Monte Carlo simulation. Various particle distributions and fluid types were compared. The output of the model was the required sterilization time to achieve the target sterilization conditions with 95% probability. This value was then used to determine the mean fluid velocity for a given tube length. Finally, the output from the model was analyzed to determine the confidence in output based on uncertainty in the input parameters. The model was more sensitive to variation in particle size distribution than fluid type for power-law fluids. The 90% confidence interval included a holding time range of 1 min. With a 95% confidence level that only 8% of the data will be below the target sterilization conditions, a maximum of 9% of the data were expected to achieve double the target level. The results of such an analysis would be useful for management decisions concerning the design of aseptic food processing operations.

Notes: Multimedia fate and exposure models are widely used to regulate the release of toxic chemicals, to set cleanup standards for contaminated sites, and to evaluate emissions in life-cycle assessment. CalTOX, one of these models, is used to calculate the potential dose, an outcome that is combined with the toxicity of the chemical to determine the Human Toxicity Potential (HTP), used to aggregate and compare emissions. The comprehensive assessment of the uncertainty in the potential dose calculation in this article serves to provide the information necessary to evaluate the reliability of decisions based on the HTP. A framework for uncertainty analysis in multimedia risk assessment is proposed and evaluated with four types of uncertainty. Parameter uncertainty is assessed through Monte Carlo analysis. The variability in landscape parameters is assessed through a comparison of potential dose calculations for different regions in the United States. Decision rule uncertainty is explored through a comparison of the HTP values under open and closed system boundaries. Model uncertainty is evaluated through two case studies, one using alternative formulations for calculating the plant concentration and the other testing the steady state assumption for wet deposition. This investigation shows that steady state conditions for the removal of chemicals from the atmosphere are not appropriate and result in an underestimate of the potential dose for 25% of the 336 chemicals evaluated.

Notes: A dynamic risk model is developed to track the occurrence and evolution of a drinking-water–borne cryptosporidiosis outbreak. The model characterizes and integrates the various environmental, medical, institutional, and behavioral factors that determine outbreak development and outcome. These include contaminant delivery and detection, water treatment efficiency, the timing of interventions, and the choices that people make when confronted with a known or suspected risk. The model is used to evaluate the efficacy of alternative strategies for improving risk management during an outbreak, and to identify priorities for improvements in the public health system. Modeling results indicate that the greatest opportunity for curtailing a large outbreak is realized by minimizing delays in identifying and correcting a drinking-water problem. If these delays cannot be reduced, then the effectiveness of risk communication in preemptively reaching and persuading target populations to avoid exposure becomes important.

Notes: The theme of one of the plenary sessions held at the 1998 annual meeting of the Society for Risk Analysis, ‘Assessing and Managing Risks in a Democratic Society,’ was chosen to reflect the current debate about the best ways to integrate social, political, economic, and technical issues into fair risk management decisions. In the papers presented here, the three plenary speakers provide their perspectives on how environmental risk management decision making is—or should be—informed by democratic processes.John D. Graham Making Sense of RiskRobert F. Kennedy, Jr. Risk, Democracy, and the EnvironmentJason Shogren Markets to Master Health and Environmental RiskAudience Questions and Answers

Notes: It was postulated that shared values determine social trust in institutions and persons related to a technology: One has trust in people holding similar salient values. Furthermore, it was hypothesized that social trust has a positive influence on perceived benefits and a negative impact on perceived risks. Results of a survey of University of Zürich students indicated that the proposed causal model explained perception of pesticides, nuclear power, and artificial sweetener very well. When social trust was controlled, the relation between risks and benefits perceived diminished. Results indicate that social trust is a key predictive factor of the perceived risks and benefits of a technology, and provide support for the salient values similarity theory of social trust.

Notes: Application of Executive Order 12898 to risk assessment of highway or rail transport of hazardous materials has proven difficult; in general, the location and conditions affecting the propagation of a plume of hazardous material released in a potential accident are unknown. Therefore, analyses have only been possible in a geographically broad or approximate manner. The advent of geographic information systems and development of software enhancements at Sandia National Laboratories have made kilometer-by-kilometer analysis of populations tallied by U.S. Census blocks along entire routes practicable. Tabulations of total or racially/ethnically distinct populations close to a route, its alternatives, or the broader surrounding area, can then be compared and differences evaluated statistically. This article presents methods of comparing populations and their racial/ethnic compositions using simple tabulations, histograms, and chi-square tests for statistical significance of differences found. Two examples of these methods are presented: comparison of two routes and comparison of a route with its surroundings.

Notes: Cultural Theory distinguishes between myths of human and physical nature as two integrated aspects of four cultural biases: hierarchy, egalitarianism, individualism, and fatalism. These biases serve as individuals' key orientations toward, for example, risk perception, public policy, and political preference. Myths of human and physical nature draw upon different intellectual histories, and an epistemological merger between the two aspects is not unproblematic. A self-administered mail survey of organized environmentalists in Norway included the theory's graphical description of myths of physical nature and verbal descriptions of myths of human nature. The respondents understood the logic of the myths of physical nature well and did not have problems in ranking them, thereby disconfirming the theory's claim that any of the myths appear irrational from the perspective of any other. The empirical results show that respondents gave the highest priority to the hierarchical myth of physical nature and that they also endorsed the egalitarian myth of human nature. Although this outcome may appear irrational from a theoretical perspective, the authors argue that (Grid/group) Cultural Theory is best served by treating the myths of physical and human nature as logically independent of one another.

Notes: This article presents a model designed to capture the major aspects of setting priorities among risks, a common task in government and industry. The model has both design features, under the control of the rankers (e.g., how success is evaluated), and context features, properties of the situations that they are trying to understand (e.g., how quickly uncertainty can be reduced). The model is demonstrated in terms of two extreme ranking strategies. The first, sequential risk ranking, devotes all its resources, in a given period, to learning more about a single risk, and its place in the overall ranking. This strategy characterizes the process for a society (or organization or individual) that throws itself completely into dealing with one risk after another. The other extreme strategy, simultaneous risk ranking, spreads available resources equally across all risks. It characterizes the most methodical of ranking exercises. Given ample ranking resources, simultaneous risk ranking will eventually provide an accurate set of priorities, whereas sequential ranking might never get to some risks. Resource constraints, however, may prevent simultaneous rankers from examining any risk very thoroughly. The model is intended to clarify the nature of ranking tasks, predict the efficacy of alternative strategies, and improve their design.

Notes: Multivariate dose-response models have recently been proposed for developmental toxicity data to simultaneously model malformation incidence (a binary outcome), and reductions in fetal weight (a continuous outcome). In this and other applications, the binary outcome often represents a dichotomization of another outcome or a composite of outcomes, which facilitates analysis. For example, in Segment II developmental toxicology studies, multiple malformation types (i.e., external, visceral, skeletal) are evaluated on each fetus; malformation status may also be ordinally measured (e.g., normal, signs of variation, full malformation). A model is proposed is for fetal weight and multiple malformation variables measured on an ordinal scale, where the correlations between the outcomes and between the offspring within a litter are taken into account. Fully specifying the joint distribution of outcomes within a litter is avoided by specifying only the distribution of the multivariate outcome for each fetus and using generalized estimating equation methodology to account for correlations due to litter clustering. The correlations between the outcomes are required to characterize joint risk to the fetus, and are therefore a focus of inference. Dose-response models and their application to quantitative risk assessment are illustrated using data from a recent developmental toxicology experiment of ethylene oxide in mice.

Notes: Adverse health outcomes from exposure to chemical agents are of increasing interest in human and ecological risk assessment and require the development of new analytical methods. Such methods must be able to capture the essence of integrated networks of biochemical pathways in a mathematically feasible fashion. Over the past three decades, Biochemical Systems Theory has been successfully applied to numerous biological systems. It is suggested here that S-system models derived from BST can provide the means for assessing chemical exposures and their effects at the metabolic level. This article briefly reviews essential concepts of S-systems and provides generic examples of chemical exposure scenarios. S-system models can be considered mechanistic, since their components are measurable quantities (e.g., concentrations, fluxes, enzyme activities, and rates). As dynamic models, they can be used to assess immediate and long-term metabolic responses to environmental stimuli. Direct mathematical analysis for low exposures leads to simple dose-response relationships, which have the form of power-law functions. Thus, if the S-system model yields an appropriate description of chemical exposure and its metabolic effects, the dose-response relationship for low exposures is linear in logarithmic coordinates. This result includes as a special case the standard linear relationship in Cartesian coordinates with zero intercept.

Notes: Books reviewed:Jonathan Ashley-Smith, Risk Assessment for Object ConservationYacov Y. Haimes Risk Modeling, Assessment, and Management

Notes: This research examines and compares perceptions held by laypeople and ecologists about risks to ecosystems, particularly risk from global climate change (GCC). A survey elicited perceptions of 31 risk characteristics for 13 GCC and 12 non-GCC risks to ecosystems. Factor analysis was used to examine the structure of layperson and expert risk perceptions. Both experts and laypeople tend to perceive GCC risks to ecosystems as less avoidable and more acceptable than risks from other causes. Compared to laypeople's perceptions, though, experts perceived GCC risks to have slightly lower impacts, be less avoidable, more acceptable, and less understandable than non-GCC risks to ecosystems. These findings may help guide efforts to communicate with laypeople about ecological risks from climate change.

Notes: This article presents arguments for the development of generic assessment endpoints for ecological risk assessment. Generic assessment endpoints would be ecological entities and attributes that are assumed to be worthy of protection in most contexts. The existence of generic assessment endpoints would neither create a requirement that they be used in every assessment nor preclude the use of other assessment endpoints. They would simply be a starting point in the process of identifying the assessment endpoints for a particular assessment. They are needed to meet legal mandates, to provide a floor for environmental degradation, to provide some consistency in environmental regulation, as exemplars for site- or project-specific assessment endpoints, to allow development of methods and models, to give risk managers the courage to act, for screening and site-independent assessments, to support environmental monitoring, to facilitate communication, and to avoid paralysis by analysis. Generic assessment endpoints should include not only a list of entities and attributes, but also explanations of each endpoint, guidance on their use and interpretation, and measures and models that could be used to estimate them.

Notes: This article develops and fits probability distributions for the variability in projected (total) job tenure for adult men and women in 31 industries and 22 occupations based on data reported by the U.S. Department of Labor's Bureau of Labor Statistics. It extends previously published results and updates those results from January 1987 to February 1996. The model provides probability distributions for the variability in projected (total) job tenures within the time range of the data, and it extrapolates the distributions beyond the time range of the data, i.e., beyond 25 years.

Notes: Exposure guidelines for potentially toxic substances are often based on a reference dose (RfD) that is determined by dividing a no-observed-adverse-effect-level (NOAEL), lowest-observed-adverse-effect-level (LOAEL), or benchmark dose (BD) corresponding to a low level of risk, by a product of uncertainty factors. The uncertainty factors for animal to human extrapolation, variable sensitivities among humans, extrapolation from measured subchronic effects to unknown results for chronic exposures, and extrapolation from a LOAEL to a NOAEL can be thought of as random variables that vary from chemical to chemical. Selected databases are examined that provide distributions across chemicals of inter- and intraspecies effects, ratios of LOAELs to NOAELs, and differences in acute and chronic effects, to illustrate the determination of percentiles for uncertainty factors. The distributions of uncertainty factors tend to be approximately lognormally distributed. The logarithm of the product of independent uncertainty factors is approximately distributed as the sum of normally distributed variables, making it possible to estimate percentiles for the product. Hence, the size of the products of uncertainty factors can be selected to provide adequate safety for a large percentage (e.g., approximately 95%) of RfDs. For the databases used to describe the distributions of uncertainty factors, using values of 10 appear to be reasonable and conservative. For the databases examined the following simple ‘Rule of 3s’ is suggested that exceeds the estimated 95th percentile of the product of uncertainty factors: If only a single uncertainty factor is required use 33, for any two uncertainty factors use 3 × 33 ≈ 100, for any three uncertainty factors use a combined factor of 3 × 100 = 300, and if all four uncertainty factors are needed use a total factor of 3 × 300 = 900. If near the 99th percentile is desired use another factor of 3. An additional factor may be needed for inadequate data or a modifying factor for other uncertainties (e.g., different routes of exposure) not covered above.

Notes: Finite mixture models, that is, weighted averages of parametric distributions, provide a powerful way to extend parametric families of distributions to fit data sets not adequately fit by a single parametric distribution. First-order finite mixture models have been widely used in the physical, chemical, biological, and social sciences for over 100 years. Using maximum likelihood estimation, we demonstrate how a first-order finite mixture model can represent the large variability in data collected by the U.S. Environmental Protection Agency for the concentration of Radon 222 in drinking water supplied from ground water, even when 28% of the data fall at or below the minimum reporting level. Extending the use of maximum likelihood, we also illustrate how a second-order finite mixture model can separate and represent both the variability and the uncertainty in the data set.

Notes: Risk perception is a phenomenon in search of an explanation. Several approaches are discussed in this paper. Technical risk estimates are sometimes a potent factor in accounting for perceived risk, but in many important applications it is not. Heuristics and biases, mainly availability, account for only a minor portion of risk perception, and media contents have not been clearly implicated in risk perception. The psychometric model is probably the leading contender in the field, but its explanatory value is only around 20% of the variance of raw data. Adding a factor of “unnatural risk” considerably improves the psychometric model. Cultural Theory, on the other hand, has not been able to explain more than 5–10% of the variance of perceived risk, and other value scales have similarly failed. A model is proposed in which attitude, risk sensitivity, and specific fear are used as explanatory variables; this model seems to explain well over 30–40% of the variance and is thus more promising than previous approaches. The model offers a different type of psychological explanation of risk perception, and it has many implications, e.g., a different approach to the relationship between attitude and perceived risk, as compared with the usual cognitive analysis of attitude.

Notes: In light of the present day risk controversies such as global warming and hormones in beef, partially caused by a more globalized world, national differences and similarities in how to manage risks become increasingly important. In this brief ‘perspective’ we focus on how risks are managed in three nations, namely Japan, Sweden, and the United States, specifically focusing on the roles of deliberation, risk analysis, and the importance of cultural factors.

Notes: Driven by differing statutory mandates and programmatic separation of regulatory responsibilities between federal, state, and tribal agencies, distinct chemical and radiation risk management strategies have evolved. In the field this separation poses real challenges since many of the major environmental risk management decisions we face today require the evaluation of both types of risks. Over the last decade, federal, state, and tribal agencies have continued to discuss their different approaches and explore areas where their activities could be harmonized. The current framework for managing public exposures to chemical carcinogens has been referred to as a ‘bottom up approach.’ Risk between 10−4 and 10−6 is established as an upper bound goal. In contrast, a ‘top down’ approach that sets an upper bound dose limit and couples with site specific As Low As Reasonably Achievable Principle (ALARA), is in place to manage individual exposure to radiation. While radiation risk are typically managed on a cumulative basis, exposure to chemicals is generally managed on a chemical-by-chemical, medium-by-medium basis. There are also differences in the nature and size of sites where chemical and radiation contamination is found. Such differences result in divergent management concerns. In spite of these differences, there are several common and practical concerns among radiation and chemical risk managers. They include 1) the issue of cost for site redevelopment and long-term stewardship, 2) public acceptance and involvement, and 3) the need for flexible risk management framework to address the first two issues. This article attempts to synthesize key differences, opportunities for harmonization, and challenges ahead.

Notes: This article presents results from the Commission of the European Communities (CEC) project ‘Safety of Shipping in Coastal Waters’ (SAFECO). The project was performed by ten European partners during the period 1995-1998. The principal aim of the SAFECO project was to determine the influences that could increase the safety of shipping in coastal waters by analyzing the underlying factors contributing to the marine accident risk level. The work reported here focuses on the Marine Accident Risk Calculation System (MARCS) that was further developed during the SAFECO project. This paper presents the methods used by MARCS, as well as data and results from a ‘demonstration of concept’ case study covering the North Sea area. The estimated accident frequencies (number of accidents per year) were compared with historical accident data, to demonstrate the validity of the modeling approach. Reasonable (within a factor of 5) to good (within a factor of 2) agreement between calculated accident frequencies and observed accident statistics was generally obtained. However, significant discrepancies were identified for some ship types and accident categories. The risk model has particular problems with estimating the accident frequency for drift grounding in general and powered grounding for ferries. It was concluded that these discrepancies are related to uncertainties in several areas, specifically in the risk model algorithms, the traffic data, the error and failure probability data, and the historical accident statistics.

Notes: This study examined the relationships of self-reported adoption of 12 seismic hazard adjustments (pre-impact actions to reduce danger to persons and property) with respondents' demographic characteristics, perceived risk, perceived hazard knowledge, perceived protection responsibility, and perceived attributes of the hazard adjustments. Consistent with theoretical predictions, perceived attributes of the hazard adjustments differentiated among the adjustments and had stronger correlations with adoption than any of the other predictors. These results identify the adjustments and attributes that emergency managers should address to have the greatest impact on improving household adjustment to earthquake hazard.

Notes: A risk assessment was conducted to determine the likelihood of certain health risks resulting from exposure to soils and food crops contaminated with polychlorinated biphenyl (PCBs). PCBs have contaminated soils, river sediments, and air in the past as a result of industrial activities at a capacitor plant located in the City of Serpukhov, Russian Federation. This risk assessment and suggestions for remediation are designed to aid in decision-making efforts by a joint Russian–American research team developing a community, national, and international response to industrial contamination. Bobovnikova et al. (The Science of the Total Environment139/140, 357–364, [1993]) have reported that PCBs are elevated in soils and sediments, breast milk, and locally grown foods in the Serpukhov area. Data from these and other investigators have been used in this risk assessment to calculate a potential cancer risk resulting from exposure to PCBs. Our assessment indicates that members of the local population may be at increased risk of cancer, and possibly other adverse health effects, as a result of PCB contamination of their environment. Because previously unassessed environmental contamination is a common problem in the former Soviet Republics, as well as many other areas of the world, we believe this type of evaluation, using known methods, can serve as a model for assessment efforts in other parts of the globe and result in remediative efforts in regions constrained by faltering economies.

Notes: Genetic differences (polymorphisms) among members of a population are thought to influence susceptibility to various environmental exposures. In practice, however, this information is rarely incorporated into quantitative risk assessment and risk management. We describe an analytic framework for predicting the risk reduction and value-of-information (VOI) resulting from specific risk management applications of genetic biomarkers, and we apply the framework to the example of occupational chronic beryllium disease (CBD), an immune-mediated pulmonary granulomatous disease. One described Human Leukocyte Antigen gene variant, HLA-DPβ1*0201, contains a substitution of glutamate for lysine at position 69 that appears to have high sensitivity (∼94%) but low specificity (∼70%) with respect to CBD among individuals occupationally exposed to respirable beryllium. The expected postintervention CBD prevalence rates for using the genetic variant (1) as a required job placement screen, (2) as a medical screen for semiannual in place of annual lymphocyte proliferation testing, or (3) as a voluntary job placement screen are 0.08%, 0.8%, and 0.6%, respectively, in a hypothetical cohort with 1% baseline CBD prevalence. VOI analysis is used to examine the reduction in total social cost, calculated as the net value of disease reduction and financial expenditures, expected for proposed CBD intervention programs based on the genetic susceptibility test. For the example cohort, the expected net VOI per beryllium worker for genetically based testing and intervention is $13,000, $1,800, and $5,100, respectively, based on a health valuation of $1.45 million per CBD case avoided. VOI results for alternative CBD valuations are also presented. Despite large parameter uncertainty, probabilistic analysis predicts generally positive utility for each of the three evaluated programs when avoidance of a CBD case is valued at $1 million or higher. Although the utility of a proposed risk management program may be evaluated solely in terms of risk reduction and financial costs, decisions about genetic testing and program implementation must also consider serious social, legal, and ethical factors.

Notes: Books reviewed:Office International Des Epizooties (World Organization for Animal Health) World Animal Health in 1998, Part 1: Reports on the Animal Health Status and Disease Control Methods and Tables on Incidence of List A Diseases and Part 2: Tables on the Animal Health Status and Disease Control MethodsPeter Sedlmeier. Lawrence Erlbaum Associates, Mahwah Improving Statistical Reasoning: Theoretical Models and Practical ImplicationsAndrew Ford. Island Press Modeling the Environment. An Introduction to System Dynamics Modeling of Environmental SystemsJacob I. Bregman. Lewis Publishers, Boca Raton Environmental Impact Statements, Second Edition

Notes: The overlapping understandings of Jewish and Christian traditions (the Traditions), both influencing and reincorporating Western culture from the Greeks to the present, underpin many of the ethical constructs of present society, in ways both obvious and subtle. The concept of justice is central to the ethical outlooks of both religious traditions. This article systematically develops values related to justice from within the Traditions and extends them to the question of intergenerational equity as proposed precepts for assessment and action. Many of the results seem familiar because they are deeply embedded in our culture. They are assertions that transcend time — the value of human life; an obligation to support the necessary interests of others, especially the powerless; the concepts of brotherhood, the common good, and stewardship of resources; and the transmission of knowledge, resources, and values through the vehicles of families and communities. Other ideas from within the Traditions, such as giving beyond the requirements of equity and the connection of human life with God whose abilities are unbounded by time, continue to draw people beyond the limits of culture. These outlooks are organized into 17 statements or proposals constitutive of this view of justice. These summary statements are used as the basis for comparing a system of principles proposed by a panel of the National Academy of Public Administration for intergenerational decision making with the views represented by the Traditions. This broaches a broader question of fairness in resource distribution. The article concludes with reference to some developed resources of the Traditions from which further insight can be drawn, and another illustration related to resource allocation. It is hoped that the article helps stimulate wider analysis of the values on which our decisions are made.

Notes: It has been suggested that the long-term discount rate for environmental goods should decrease at longer delays. One justification for this suggestion is that human judgments support it. This article presents an experiment showing that judgments concerning discount rates are internally inconsistent. These results point to potential problems with the use of judgments referenda for determining discount rates in cost-benefit analyses.

Notes: Approximately $6 billion is spent annually in the United States on the cleanup of sites regulated under the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA, or Superfund). The current health risks posed by such sites are thought to be quite small; the expenditures are justified primarily as protecting hypothetical future residents of these sites. Approximately 0.05% of this amount, or $3 million, is spent annually by the U.S. government on the detection of asteroids or comets that could strike the earth. Such damaging impacts do occur from time to time — most recently in 1908 in an unpopulated region of Siberia — but no person is confirmed ever to have died as a result. Anticipated impacts over the course of 1 million years would yield deaths that, when annualized, total approximately 4,000 per year. The risk reduction goal for CERCLA is 15 orders of magnitude greater than that for asteroid/comet detection. A modest increase in resources devoted to asteroid detection would greatly increase the chances of early detection of a threatening object, allowing an effective defense to be attempted. This article argues that the much lower risk-to-resources ratio for CERCLA cleanups than for asteroid and comet detection can be explained by four primary factors: (1) the regard for future generations, since CERCLA benefits mainly the unborn; (2) concrete fears, since toxics are much more feared than asteroids or comets; (3) the source of the threat, since toxic contamination is caused by human beings, unlike impacts from space objects; and (4) the greater political constituencies for hazardous waste cleanup than for space object detection.

Notes: Exposure to chemical contaminants in various media must be estimated when performing ecological risk assessments. Exposure estimates are often based on the 95th-percentile upper confidence limit on the mean concentration of all samples, calculated without regard to critical ecological and spatial information about the relative relationship of receptors, their habitats, and contaminants. This practice produces exposure estimates that are potentially unrepresentative of the ecology of the receptor. This article proposes a habitat area and quality-conditioned exposure estimator, E[HQ], that requires consideration of these relationships. It describes a spatially explicit ecological exposure model to facilitate calculation of E[HQ]. The model provides (1) a flexible platform for investigating the effect of changes in habitat area, habitat quality, foraging area, and population size on exposure estimates, and (2) a tool for calculating E[HQ] for use in actual risk assessments. The inner loop of a Visual Basic® program randomly walks a receptor over a multicelled landscape—each cell of which contains values for cell area, habitat area, habitat quality, and concentration—accumulating an exposure estimate until the total area foraged is less than or equal to a given foraging area. An outer loop then steps through foraging areas of increasing size. This program is iterated by Monte Carlo software, with the number of iterations representing the population size. Results indicate that (1) any single estimator may over- or underestimate exposure, depending on foraging strategy and spatial relationships of habitat and contamination, and (2) changes in exposure estimates in response to changes in foraging and habitat area are not linear.

Notes: Ingestion of contaminated soil by children may result in significant exposure to toxic substances at contaminated sites. Estimates of such exposure are based on extrapolation of short-term-exposure estimates to longer time periods. This article provides daily estimates of soil ingestion on 64 children between the ages of 1 and 4 residing at a Superfund site; these values are employed to estimate the distribution of 7-day average soil ingestion exposures (mean, 31 mg/day; median, 17 mg/day) at a contaminated site over different time periods. Best linear unbiased predictors of the 95th-percentile of soil ingestion over 7 days, 30 days, 90 days, and 365 days are 133 mg/day, 112 mg/day, 108 mg/day and 106 mg/day, respectively. Variance components estimates (excluding titanium and outliers, based on Tukey's far-out criteria) are given for soil ingestion between subjects (59 mg/day)2, between days on a subject (95 mg/day)2, and for uncertainty on a subject-day (132 mg/day)2. These results expand knowledge of potential exposure to contaminants among young children from soil ingestion at contaminated sites. They also provide basic distributions that serve as a starting point for use in Monte Carlo risk assessments.

Notes: The purpose of this study was to explore the utility of protection motivation theory (PMT) in the context of mass media reports about a hazard. Content elements of a hazard's severity, likelihood of occurring, and the effectiveness of preventive actions were systematically varied in a news story about a fabricated risk: exposure to fluorescent lighting lowering academic performance. Results of this experiment (N = 206) suggest that providing information about the severity of a hazard's consequences produces greater information seeking. In addition, information about levels of risk, severity, and efficacy combined jointly to produce greater rates of willingness to take actions designed to avoid the hazard. Results are seen as providing general support for PMT and are discussed within the broader framework of information seeking and heuristic and systematic information processing.

Notes: Food safety concerns and the demand for organically grown produce have increased significantly in the United States over the last decade. Key differences in lifestyle characteristics, food safety attitudes and beliefs, perceived food safety risks, and valuation of health risk reductions between organic and conventional food buyers remain largely unknown, however. To better characterize how buyers of organic fresh produce differ from their conventional counterparts, over 700 food shoppers were sampled from ten major retail stores in the Boston area. Survey results show that self-reported organic buyers are more likely than conventional buyers to engage in a variety of health-promoting and environmentally friendly behaviors. Organic buyers are less trusting of federal food safety agencies than are conventional buyers, and perceive greater benefits associated with organically grown produce than do their conventional counterparts. Further, organic buyers have significantly higher risk perceptions than do conventional buyers for food safety hazards associated with conventionally grown produce. Compared to conventional buyers, organic produce buyers also perceive significant risk reductions associated with switching to organically grown produce and are willing to pay a higher price to reduce perceived food safety risks. Few sociodemographic differences between buyer types were observed, possibly due to how organic and conventional food stores were matched. Survey findings highlight the need for greater public education about a range of food safety issues and farming practices to ensure that consumers are making informed decisions in the marketplace.

Notes: Toxicologists are often interested in assessing the joint effect of an exposure on multiple reproductive endpoints, including early loss, fetal death, and malformation. Exposures that occur prior to mating or extremely early in development can adversely affect the number of implantation sites or fetuses that form within each dam and may even prevent pregnancy. A simple approach for assessing overall adverse effects in such studies is to consider fetuses or implants that fail to develop due to exposure as missing data. The missing data can be imputed, and standard methods for the analysis of quantal response data can then be used for quantitative risk assessment or testing. In this article, a new bias-corrected imputation procedure is proposed and evaluated. The procedure is straightforward to implement in standard statistical packages and has excellent operating characteristics when used in combination with a marginal model fit with generalized estimating equations. The methods are applied to data from a reproductive toxicity study of Nitrofurazone conducted by the National Toxicology Program.

Notes: This article introduces and develops a modeling framework for exposing risks in the form of human errors and adverse consequences in high-risk systems. The modeling framework is based on two components: a two-dimensional theory of accidents in systems developed by Perrow in 1984, and the concept of multiple system perspectives. The theory of accidents differentiates systems on the basis of two sets of attributes. One set characterizes the degree to which systems are interactively complex; the other emphasizes the extent to which systems are tightly coupled. The concept of multiple perspectives provides alternative descriptions of the entire system that serve to enhance insight into system processes. The usefulness of these two model components derives from a modeling framework that cross-links them, enabling a variety of work contexts to be exposed and understood that would otherwise be very difficult or impossible to identify. The model components and the modeling framework are illustrated in the case of a large and comprehensive trauma care system. In addition to its general utility in the area of risk analysis, this methodology may be valuable in applications of current methods of human and system reliability analysis in complex and continually evolving high-risk systems.

Notes: The choice of a dose-response model is decisive for the outcome of quantitative risk assessment. Single-hit models have played a prominent role in dose-response assessment for pathogenic microorganisms, since their introduction. Hit theory models are based on a few simple concepts that are attractive for their clarity and plausibility. These models, in particular the Beta Poisson model, are used for extrapolation of experimental dose-response data to low doses, as are often present in drinking water or food products. Unfortunately, the Beta Poisson model, as it is used throughout the microbial risk literature, is an approximation whose validity is not widely known. The exact functional relation is numerically complex, especially for use in optimization or uncertainty analysis. Here it is shown that although the discrepancy between the Beta Poisson formula and the exact function is not very large for many data sets, the differences are greatest at low doses—the region of interest for many risk applications. Errors may become very large, however, in the results of uncertainty analysis, or when the data contain little low-dose information. One striking property of the exact single-hit model is that it has a maximum risk curve, limiting the upper confidence level of the dose-response relation. This is due to the fact that the risk cannot exceed the probability of exposure, a property that is not retained in the Beta Poisson approximation. This maximum possible response curve is important for uncertainty analysis, and for risk assessment of pathogens with unknown properties.

Notes: The installation of passenger-side airbags in new vehicles complicates efforts to maximize child safety in motor vehicle crashes. It has been recommended by both public and private organizations that children sit in the rear seat with proper restraint to achieve maximum safety. Drivers now need to decide whether a child should be restrained, where the child should be seated (front versus rear), and whether the child should be seated in front of a passenger-side airbag. This research was undertaken to determine which choice minimizes the risk of fatality to children. Using data from the U.S. Fatality Analysis Reporting System for calendar years 1989 to 1998, fatal vehicle crashes with child passengers younger than 13 years were analyzed. The effectiveness of passenger-side airbags and rear seating for children, by age category and restraint use, was estimated using the double-pair comparison method. For each of four age categories, the fatality risk of each possible combination of restraint use, seating location, and airbag presence was also estimated using logistic regression. Passenger airbags were associated with an increase in child fatality risk of 31% for restrained children, and 84% for unrestrained children. Passenger airbags did appear to offer protection to restrained 9- to 12-year-old children. Restraint use and rear seating were associated with statistically significant reductions in the odds of a child dying in a crash. In order to minimize child fatality risk, parents should seat children in the rear of the vehicle while using the proper child restraint system, especially in vehicles with passenger airbags. These findings support current public education efforts in the United States.

Notes: The electrophilic nature of some contact sensitizers, that is, chemicals that cause allergic contact dermatitis (ACD), is also characteristic of genotoxic tumorigens. Electrophiles can adduct protein, which is the basis for ACD, as well as DNA, which is the basis for mutagenicity and carcinogenicity. This suggests that some electrophilic contact sensitizers may be genotoxic tumorigens. To further investigate this matter, we evaluated 146 chemicals that had been bioassayed for tumorigenicity and mutagenicity in the National Toxicology Program, with an analysis of structure-activity relationships for contact sensitization. Using the data from this analysis and from other sources, the proportion of the contact sensitizers that were both mutagenic and tumorigenic was found to range from 20% to 28%. This finding suggests that there may be in the order of 90 genotoxic tumorigens for rodents among the approximately 384 chemicals that have been validated as contact sensitizers for humans.

Notes: Pipeline damage by dropped objects from crane activities is a significant hazard for offshore platform installations. In this paper a probabilistic methodology is utilized for the estimation of the pipeline impact and rupture frequencies; this information is obtained both for the overall pipeline section exposed to the hazard and for a number of critical locations along the pipeline route. The presented algorithm has been implemented in a computer program that allows the analysis of a large number of possible drop points and pipeline target point locations. This methodology may be used in common risk analysis studies for evaluating the risk for platform personnel from dropped objects; however, the proposed technique may also be useful for other applications where engineering judgment has so far been the main driving criterion. In particular, two sample cases have been analyzed. The first one is the problem of selecting the best approaching route to a platform. By analyzing different route alternatives, a reduction of the impact frequency and therefore of the risk for the platform personnel may be achieved. The second application deals with the selection of the location for a safety valve at the riser base. The analysis may give useful information, such as the highest impact frequency location and the rupture frequencies upstream and downstream of the valve as a function of the valve position; this information, together with the transported medium inventory upstream of the valve, may give the designer a documented and justifiable rationale for selecting the best location for the valve from a safety point of view.

Notes: The simplified Conjoint Expected Risk (CER) model by Holtgrave and Weber posits that perceived risk is a linear combination of the subjective judgments of the probabilities of harm, benefit, and status quo, and the expected harm and benefit of an activity. It modifies Luce and Weber's original CER model—that uses objective information to evaluate financial gambles—to accommodate activities such as health/technology activities where values of the model variables are subjective. If the simplified model is a valid modification of the original model, its performance should not be sensitive to the use of subjective information. However, because people may evaluate information differently when objective information is provided to them than when they generate information on their own, the performance of the simplified CER model may not be robust to the source of model-variable information. We compared the use of objective and subjective information, and results indicate that the estimates of the simplified CER model parameters and the proportion of variance in risk judgments accounted for by the model are similar under these two conditions. Thus, the simplified CER model is viable with activities for which harm and benefit information is subjective.

Notes: A causal model explaining acceptance of gene technology was tested. It was hypothesized that trust in institutions using gene technology or using modified products has a positive impact on perceived benefit and a negative influence on perceived risk of this technology. Furthermore, perceived benefit and perceived risk determine acceptance of biotechnology. In other words, trust has an indirect influence on the acceptance of the technology. The postulated model was tested using structural equation modeling procedures and data from a random quota sample of 1001 Swiss citizens between 18 and 74 years old. Results indicated that the proposed model fits the data very well. The same causal model explains females' and males' acceptance of gene technology. Gender differences were found for the latent variables trust, perceived benefit, and acceptance of gene technology. Females indicated more trust, perceived less benefit, and demonstrated less acceptance than did males. No significant difference was observed for perceived risk. The implications of the results are discussed.

Notes: Any practical process of risk ranking must group hazards into a manageable number of categories. Defining such categories requires value choices that can have important implications for the rankings that result. Most risk-management organizations will find it useful to begin defining categories in terms of environmental loadings or initiating events. However, the resulting categories typically need to be modified in light of other considerations. Risk-ranking projects can benefit from considering several alternative categorization strategies and drawing upon elements of each in developing their final categorization of risks. In principle, conducting multiple ranking exercises by using different categorizations could be interesting and useful. In practice, agencies are unlikely to have either the resources or patience to do this, but other groups in society might. Done well, such additional independent rankings could add valuable inputs to democratic risk-management decision making.

Notes: Two-year chronic bioassays were conducted by using B6C3F1 female mice fed several concentrations of two different mixtures of coal tars from manufactured gas waste sites or benzo(a)pyrene (BaP). The purpose of the study was to obtain estimates of cancer potency of coal tar mixtures, by using conventional regulatory methods, for use in manufactured gas waste site remediation. A secondary purpose was to investigate the validity of using the concentration of a single potent carcinogen, in this case benzo(a)pyrene, to estimate the relative risk for a coal tar mixture. The study has shown that BaP dominates the cancer risk when its concentration is greater than 6,300 ppm in the coal tar mixture. In this case the most sensitive tissue site is the forestomach. Using low-dose linear extrapolation, the lifetime cancer risk for humans is estimated to be: Risk 〈 1.03 × 10−4 (ppm coal tar in total diet) + 240 × 10−4 (ppm BaP in total diet), based on forestomach tumors. If the BaP concentration in the coal tar mixture is less than 6,300 ppm, the more likely case, then lung tumors provide the largest estimated upper limit of risk, Risk 〈 2.55 × 10−4 (ppm coal tar in total diet), with no contribution of BaP to lung tumors. The upper limit of the cancer potency (slope factor) for lifetime oral exposure to benzo(a)pyrene is 1.2 × 10−3 per μg per kg body weight per day from this Good Laboratory Practice (GLP) study compared with the current value of 7.3 × 10−3 per μg per kg body weight per day listed in the U.S. EPA Integrated Risk Information System.

Notes: Earlier work with decision trees identified nonseparability as an obstacle to minimizing the conditional expected value, a measure of the risk of extreme events, by the well-known method of averaging out and folding back. This first of two companion papers addresses the conditional expected value that is defined as the expected outcome assuming the exceedance of a threshold β, where β is preselected by the decision maker. An approach is proposed to overcome the need to evaluate all policies in order to identify the optimal policy. The approach is based on the insight that the conditional expected value is separable into two constituent elements of risk and can thus be optimized along with other objectives, including the unconditional expected value of the outcome, by using a multiobjective decision tree. An example of sequential decision making for improving highway capacity is given.

Notes: Methyl mercury (meHg) contamination of fish is the leading cause of fish consumption advisories in the United States. These advisories have focused upon repeated or chronic exposure, whereas risks during pregnancy may also exist from a single-meal exposure if the fish tissue concentration is high enough. In this study, acute exposure to meHg from a single fish meal was analyzed by using the one-compartment meHg biokinetic model to predict maternal hair concentrations. These concentrations were evaluated against the mercury hair concentration corresponding to the U.S. Environmental Protection Agency's reference dose (RfD), which is intended to protect against neurodevelopmental effects. The one-compartment model was validated against blood concentrations from three datasets in which human subjects ingested meHg in fish, either as a single meal or multiple meals. Model simulations of the single-meal scenario at different fish meHg concentrations found that concentrations of 2.0 ppm or higher can be associated with maternal hair concentrations elevated above the RfD level for days to weeks during gestation. A single-meal fish concentration cutoff of 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:02724332:RISA004:ges" location="ges.gif"/〉 2.0 ppm is an important consideration, especially because this single high exposure event might be in addition to a baseline meHg body burden from other types of fish consumption. This type of single-meal advisory requires that fish sampling programs provide data for individual rather than composited fish, and take into account seasonal differences that may exist in fish concentrations.

Notes: How does one deal with problems of risk transfer if it is the case that increasing risks to future generations decreases the risks to present generations, and increasing the risks to present generations decreases the risks to future generations? In the case of high-level nuclear waste and spent fuel, for example, should billions of dollars be spent to secure the wastes and protect future generations, or should the same monies be spent on present-day needs, under the assumption that future generations will be better able to deal with the waste than we are at present? Although these questions may appear insoluble, they become less so when one recognizes several common ethical and logical errors that beset many discussions of technological risk and duties to future generations. After briefly explaining the grounds for inter- and intragenerational equity, this analysis argues for three propositions about many treatments of inter- and intragenerational ethics: (1) these discussions often err because they frame policy arguments in terms that ignore rights and focus on maximizing welfare or utility, (2) they err because they frequently frame policy arguments in ways that set inter- and intragenerational welfare at odds, when they are not, because they ignore ameliorating practices and the conditions for proxy consent, and (3) they also err because they engage in risk practices that do not match their risk rhetoric.

Notes: A discount rate for the consumption of future generations is typically composed of two parts. One is a “pure” time preference for immediate over postponed consumption, the other a declining marginal utility as consumption increases. The costs of greenhouse abatement, however, for at least the first 50 years, will be borne by the developed countries; the benefits will accrue to the presently undeveloped. Pure time preference always relates to one's own consumption; it has no relevance here. Consumption transfers over time will be from richer to poorer, from lower to higher marginal utility. It is a foreign aid program and it ought to have to compete with more direct foreign aid, which can benefit the very poor rather than their much-better-off descendants.

Notes: Policies to mitigate potential damages from global climate change impose costs on the current generation to provide benefits to future generations. This article examines how comparisons among three stylized policies — business-as-usual, mitigation of climate change, and compensation for climate damages — depend on social preferences with respect to risk and intertemporal equity. Also examined is the opportunity-cost criterion, which asserts that mitigation should not be chosen if its net present value is smaller than that of business-as-usual. Analysis reveals that the discount factor used to evaluate whether mitigation satisfies this criterion depends on preferences regarding risk and intertemporal inequality of consumption, and on the risk of the compensation policy. Risk aversion favors mitigation over business-as-usual. If society is neutral to inequality, risk aversion disfavors compensation, but if society is inequality averse, the effect of risk aversion on preferences between compensation and business-as-usual is ambiguous. Inequality aversion tends to favor business-as-usual over both alternative policies provided that, roughly speaking, the anticipated future improvements in welfare exceed the anticipated climate damages.

Notes: Intergenerational justice is implicit in international commitments to sustainability. If ecological, economic, and social components of sustainability are to be achieved, there is a necessity for intergenerational justice considerations to be included in decision making. The present generation's risk judgments should include consideration of the possible outcomes for their children. But intergenerational issues cannot be considered in isolation from other current risk and fairness concerns. This article reports on a community-based integrative model that describes justice and other attitudes and motivations that determine community and individual proenvironmental behavior in two nations: Germany and Australia. This model can account for a considerable amount of the variance in political compliance as well as various proenvironmental behaviors. Group or individual self-interests have nearly no effects on global protective behavior. It is shown that universal as well as contextual principles, including distributive (within or between generations), procedural, and interactive justice, play a crucial role in fairness judgments. Other principles are also taken into account, such as efficiency, environmental rights, and rights to economic welfare. The results are discussed in relation to the importance of complex community fairness judgments in predicting and evaluating acceptance of political decisions, and for promoting proenvironmental behavior.

Notes: Estimation of uncertainties associated with model predictions is an important component of the application of environmental and biological models. “Traditional” methods for propagating uncertainty, such as standard Monte Carlo and Latin Hypercube Sampling, however, often require performing a prohibitive number of model simulations, especially for complex, computationally intensive models. Here, a computationally efficient method for uncertainty propagation, the Stochastic Response Surface Method (SRSM) is coupled with another method, the Automatic Differentiation of FORTRAN (ADIFOR). The SRSM is based on series expansions of model inputs and outputs in terms of a set of “well-behaved” standard random variables. The ADIFOR method is used to transform the model code into one that calculates the derivatives of the model outputs with respect to inputs or transformed inputs. The calculated model outputs and the derivatives at a set of sample points are used to approximate the unknown coefficients in the series expansions of outputs. A framework for the coupling of the SRSM and ADIFOR is developed and presented here. Two case studies are presented, involving (1) a physiologically based pharmacokinetic model for perchloroethylene for humans, and (2) an atmospheric photochemical model, the Reactive Plume Model. The results obtained agree closely with those of traditional Monte Carlo and Latin hypercube sampling methods, while reducing the required number of model simulations by about two orders of magnitude.

Notes: The goal of this investigation was to assess if and when a crew of paving workers is uniformly exposed to bitumen fume, organic vapor, and benzo(a)pyrene. Data on paving workers with up to six repeated exposure measurements were extracted from a database of exposure measurements developed within a study of the European asphalt industry (N = 591). The uniformity of exposures to bitumen fume, organic vapor, and benzo(a)pyrene was evaluated while grouping individuals by job title, primary tasks, crew membership, and use of coal tar (discontinued in Western Europe). The estimated ranges within which 95% of individual mean exposures were expected to fall (BWR0.95) were used to assess exposure uniformity. Variance components were estimated by constructing mixed-effects models, with grouping variables as fixed effects and worker identity as random effect. The influence of duration of the sampling survey on estimates of exposure variability for a crew was also examined. There was a substantial variability in exposures between paving crews, as well as persons holding the same job or doing the same task, but each crew was uniformly exposed to bitumen fume and benzo(a)pyrene (BWR0.95 2 and 1, respectively). Workers within the same crew engaged in paving with coal tar – containing binders were not, however, uniformly exposed to benzo(a)pyrene. Also, organic vapor exposures were not uniform among the members of a paving crew (BWR0.95 = 15). Sampling campaigns of up to 7 months had little impact on the estimates of within- and between-worker variability. These findings should assist investigators studying paving operations in optimizing their sampling, exposure assessment, and risk evaluation protocols. The results support the notion that only empirically determined predictors of exposure can yield optimal grouping, unlike a priori grouping strategies based on general descriptors such as jobs title or tasks performed.

Notes: This study examines whether people pursue the total elimination of environmental risks even if the risk reduction occurs incrementally and requires steadily increasing amounts of money to achieve. Participants' willingness to pay (WTP) was measured for various levels of reduction in the risk of cancer caused by dioxin. Results showed that: (1) people were willing to pay more for an initial reduction in risk than for subsequent reductions, (2) the WTP for the final risk decrement—which achieved total risk elimination—was higher than the WTP for either of the two previous decrements but barely half of that for the first reduction, and (3) the manner in which the questions were framed did not affect participants' responses. These results suggest that the public will not always try to pursue perfect safety at the cost of a large sum of money, but rather may seek a decreasing expenditure as the risk level is reduced.

Notes: Nuclear power, nuclear waste, and nuclear weapons raise substantial public concern in many countries. While new support for nuclear power can be found in arguments concerning greenhouse gases and global warming, the long-term existence of radioactive waste has led to requirements for 10,000-year isolation. Some of the support for such requirements is based on intergenerational equity arguments. This, however, places a very high value on lives far in the future. An alternative is to use discounting, as is applied to other resource applications. Nuclear weapons, even though being dismantled by the major nations, are growing in number due to the increase in the number of countries possessing these weapons of mass destruction. This is an unfortunate legacy for future generations.

Notes: The philosophic and practical aspects of intergenerational planning for a 50 – 100-year time frame are reviewed, with recognition of its speculative quality. Society's near term choice of future physical pathways based on comparative quantitative benefit/cost/risk analyses of alternatives is usually modified by the intervention of a variety of time-dependent, nontechnical value systems. Further, the continuous competition among society's disparate technical systems, capital investment choices, and planning objectives all contribute to the uncertainty of the intergenerational outcome of any plan. Nevertheless, the quantitative planning process provides an essential base. Benefit/cost/risk projections are discussed for both the case with a historical database and the case without such a historical base. The end-objectives and continuous nature of such benefit/cost/risk analyses are described.

Notes: The reasons commonly given for discounting future costs and benefits are doubtfully applicable to future injuries: in particular, time preference justifies neither inter- nor intragenerational discounting. The cost of future injuries could be discounted on grounds that a smaller sum, invested at interest, is needed to pay a given level of ex post monetary compensation the further in the future the injury occurs. This effect is offset, however, by the diminishing marginal utility of compensation, if consumption is otherwise increasing. Depending on the elasticity of marginal utility of consumption, on whether consumption is growing at an optimal rate, and on the time period considered, the implicit discount rate may be positive, zero, or negative (even indefinitely so). There is no prospect of conventional discounting dealing appropriately with the cost of injuries to either future or present generations.

Notes: There is no such thing as intergenerational decision making, at least not yet. In fact, there is no such thing as intragenerational decision making in the context of maximizing overall social good given resource limitations, there are just decisions being made in an ad hoc fashion. Even if one assumes that there is such a thing as intragenerational decision making, no uniform standard or guidance exists to make societal decisions for the common good. Risks to society are judged unevenly within the same agency and across agencies. Decisions are made in isolation and not weighed in the societal context of what is intra or intergenerationally important. The National Academy of Public Administration (NAPA) has set forth a framework for intergenerational decision making that provides a consistent and fair basis for making tough decisions in order to address difficult issues such as the long-term disposal of nuclear wastes. NAPA recognizes that there is an intergenerational obligation that must encompass broader questions than the narrow issue of waste disposal since resources are finite and needs are great. The fundamental principles are based on sustainability with the overarching objective that “no generation should needlessly, now or in the future, deprive its successors of the opportunity to enjoy a quality of life equivalent to its own.” Coupled with this objective are four supporting principles of trusteeship, sustainability, chain of obligation, and precaution. The NAPA process also recognizes that no decision can be final and that a “rolling future” view is better than making decisions for “all time.” It attempts to balance the needs of the present with those of the future in an open and transparent process that is aimed at producing a decision, not just endless analysis. The U.S. Congress and president should develop a rational standard by which to judge laws that involve intra and intergenerational issues relative to the overall societal good. Present regulations need to be evaluated relative to a uniform level of risk and benefit to assess where the limited money available can do the most good for both the present and future generations in the context of NAPA sustainability principles. It is hoped that decision makers will take a serious look at this process since it can work to resolve stakeholder stalemate.

Notes: A probabilistic risk assessment was conducted to evaluate the likelihood and ecological significance of potential toxic effects of diazinon in the Sacramento – San Joaquin system. Diazinon, an organophosphorus insecticide, is used in the Sacramento – San Joaquin River Basin as a dormant spray on almonds and other tree crops, as well as for other agricultural and urban applications. Diazinon and other pesticides have been detected in the Sacramento and San Joaquin Rivers and their tributaries. Diazinon exposure was characterized based on monitoring programs conducted in 1991 – 94. Diazinon effects were characterized using laboratory toxicity data for 63 species, supplemented by results from field mesocosm and microcosm studies. The assessment addressed the possibility that reductions in invertebrate populations could lead to impacts on species of fish that feed on those invertebrates. The risk assessment concluded that fish in these rivers are not at risk from the direct effects of diazinon in the water. Invertebrates are at greater risk, especially in agriculturally dominated streams and drainage channels during January and February. Cladocerans—including Daphnia magna and Ceriodaphnia dubia, two common bioassay species—are especially sensitive to diazinon and other organophosphates and are likely to be subject to acute toxic effects in some locations at some times. Any ecological damage that may occur, however, is brief and limited to cladocerans. None of the fish species of concern depend on cladocerans as critical components of their diet. Invertebrates that are not affected by observed concentrations of diazinon (copepods, mysids, amphipods, rotifers, and insects) are preferred foods for fish in the Sacramento – San Joaquin system.

Notes: Land application is one of the major methods of managing municipal sludge in China. The sludge is used for fertilizing and conditioning soil, but due to the high concentration of heavy metals and other chemicals that it contains, improper use of sludge will lead to the contamination of farmland soil. To provide guidance on the application of sludge in China, the Control Standards for Pollutants in Sludge for Agricultural Use (CSPSAU) were enacted, and implemented in 1985. Afterwards, the National Environment Quality Standards for Soil (NEQSS) were also formulated and put into effect in 1996. In this article, these two national standards were examined by means of exposure assessment. The main exposure pathway to humans that was considered was dietary intake of crops grown on the sludge-applied farmland. Five major types of agricultural crops (rice, wheat, tuber roots, vegetables, and fruits) and three groups of exposure population (the urban individual group, the rural sludge-applying individual group, and the rural sludge nonapplying individual group) were assessed. This case study in Tianjin, China, shows the necessity of reexamining the national standards of the CSPSAU and the NEQSS in the context of risk assessment. More comprehensive surveys and monitoring programs assessing heavy metals contained in farmland soils and crop tissues will be necessary for examining the risks to human health.

Notes: This article investigates potential differences in risk perception between experts (loss-prevention managers in the U.K. oil and gas production industry) and nonexperts (managers and students). Extant research on expert versus nonexpert perceptions of risk is reviewed, followed by the present study concerning risk perceptions of seven pen-picture scenarios involving the occurrence of hazardous events in the U.K. oil and gas production industry. In contrast to many of the earlier studies of expert versus nonexpert perceptions of risk, the present analysis concludes that experts did not judge the overall riskiness of the portrayed hazardous events as less risky than the nonexperts. Nevertheless, the experts believe more strongly than our nonexperts that the risks portrayed in the scenarios pose little threat to future generations, are more precisely known, and are relatively controllable. Use of multiple regression analysis to help uncover the basis of overall riskiness assessments for expert and lay respondents was inconclusive, however. Finally, little evidence was found that nonexperts were any more heterogeneous in their risk perceptions than experts. It may be that the nature of the risks assessed in the present study may account for the general lack of clear expert versus nonexpert differences in overall perceptions of the riskiness of hazardous events in the North Sea. Earlier findings of strong expert versus nonexpert differences in risk perception assessed hazards of major public concern. It is inferred that using such extreme hazards may have resulted in an exaggerated view of differences in expert versus public (nonexpert) perception of risk.

Notes: Efforts to reduce pesticide-related risks to consumers and farmworkers often neglect the possibility that measures to reduce the target risk may introduce or enhance countervailing risks. These may arise from substitute pesticides or pest-control practices, from increased levels of pests or pest-related hazards, from increased levels of toxic natural pesticides in plants, from increased costs and decreased consumption of health-enhancing fruits and vegetables, or from direct income effects on consumers and farmers. The effect of the countervailing risks may partially or completely offset the reduction in the target risk. A risk-trade-off analysis was conducted of a potential ban on the use of organophosphate and carbamate (OP/Carbamate) insecticides in U.S. agriculture. Although this scenario is extreme, it has the analytic virtue of dispensing with the infinite number of “next-best” OP/Carbamates that might be substituted for specific combinations of crops and pests should only selected uses be banned. The analysis relies on detailed descriptions of the alternative pesticides and pest-control measures that would be used for each of 14 major crops. The effects of pest-control cost changes on prices and consumption and effects on consumer and producer incomes are projected using a general-equilibrium economic model. Several countervailing risks that may be significant were found, including acute toxicity to farmworkers from substitute pesticides, cancer and noncancer risks from substitute pesticides, and mortality induced by changes in disposable income. Other countervailing risks are more difficult to estimate or weigh. Potential increases in natural plant pesticides following an OP/Carbamate ban are discussed but data are lacking to quantify the effects. Changes in diet following the ban have both positive and negative effects, and the ultimate change is difficult to estimate. Although a net risk cannot be estimated, several approaches were illustrated that would be useful in risk-trade-off analyses. Key factors complicating comprehensive analysis of risk/risk trade-offs for pesticides were also identified, including data gaps and shortcomings of current risk assessment methods.

Notes: Recent research indicates that social trust of those who manage a hazard is strongly correlated to judgments about the hazard's risk and benefits. The present study investigates the more specific question of “For which hazards is this?” It was postulated that when an individual lacks knowledge about a hazard, social trust of authorities managing the hazard determines perceived risks and benefits. On the other hand, when an individual has personal knowledge about a hazard and therefore does not need to rely on managing authorities, social trust is unrelated to judged risks and benefits. Participants (N = 91) assessed risks, benefits, and trust in managing authorities and personal knowledge associated with 25 hazardous technologies and activities. As expected, strong correlations between social trust and judged risks and benefits were observed for hazards about which people did not possess much knowledge. No significant correlations between social trust and judged risks and benefits were found for hazards about which people were knowledgeable. Results suggest that the lay public relies on social trust when making judgments of risks and benefits when personal knowledge about a hazard is lacking. Replicating findings of other studies, the present study also found negative correlations between perceived risks and perceived benefits. When social trust was controlled for, correlations between perceived risks and benefits diminished. Implications of the results for risk management are discussed.

Notes: Books reviewed:Ragnar Lofstedt and Lynn Frewer, eds., The Earthscan Reader in Risk & Modern Society Charles Vincent and Bas De Mol, eds. Pergamon Press, Amsterdam, 2000 Safety in MedicineHans Marquardt, Siegfried Schafer, Rodger McClellan, and Frank Welsch, eds., Toxicology

Notes: One hundred twenty-two members (experts) of the Society for Risk Analysis completed a mailed questionnaire and 150 nonexperts completed a similar questionnaire on the World Wide Web. Questions asked included those about priorities on personal and government action for risk reduction, badness of the risk, number of people affected, worry, and probabilities for self and others. Individual differences in mean desire for action were largely explained in terms of worry. Worry, in turn, was largely affected by probability judgments, which were lower for experts than for nonexperts. Differences across risks in the desire for action, within each subject, were also determined largely by worry and probability. Belief in expert knowledge about the risk increased worry and the priority for risk reduction. A second study involving 91 nonexperts (42 interviewed and 49 on the Web) replicated the main findings for nonexperts from the first study. Interviews also probed the determinants of worry, attitudes toward government versus personal control, and protective behaviors.

Notes: Radiation protection authorities have seen a potential for applying multiattribute risk analysis in nuclear emergency management and planning to deal with conflicting objectives, different parties involved, and uncertainties. This type of approach is expected to help in the following areas: to ensure that all relevant attributes are considered in decision making; to enhance communication between the concerned parties, including the public; and to provide a method for explicitly including risk analysis in the process. A multiattribute utility theory analysis was used to select a strategy for protecting the population after a simulated nuclear accident. The value-focused approach and the use of a neutral facilitator were identified as being useful.

Notes: One of the characteristics of modern industrial development is the emergence of a new typology of accidents whose effects can be spread, in space as well as in time, well beyond the borders of the installations where they occur, sometimes impacting the local population and the environment in a catastrophic fashion. This is the result of a number of factors that have changed the risk profile of modern industrial activities. For a number of reasons, the developing countries have proved to be more vulnerable to industrial disasters. Three of the most catastrophic industrial accidents—Bhopal, San Juan de Ixhuatepec, and Cubatão—occurred in developing countries, claiming thousands of lives. During the 1970s and 1980s the higher degree of public visibility of industrial hazards as a result of serious accidents, led to the creation, especially in the more industrialized countries, of regulations for greater control over industrial activities, either by means of new laws or by updating existing legislation. Some of these regulations were designed to improve the response to accidents with potential impacts outside the industrial sites. This article attempts to describe the current status and identify the shortcomings of off-site emergency planning for hazardous industrial areas in Brazil. The most important problems are the lack of specific legislation and the absence of awareness and active participation of public authorities. The experience of an off-site emergency planning process for a Brazilian industrial area is presented. This experience illustrates how difficult it is to prepare and implement emergency planning processes in an industrializing country.

Notes: Risks associated with toxicants in food are often controlled by exposure reduction. When exposure recommendations are developed for foods with both harmful and beneficial qualities, however, they must balance the associated risks and benefits to maximize public health. Although quantitative methods are commonly used to evaluate health risks, such methods have not been generally applied to evaluating the health benefits associated with environmental exposures. A quantitative method for risk-benefit analysis is presented that allows for consideration of diverse health endpoints that differ in their impact (i.e., duration and severity) using dose-response modeling weighted by quality-adjusted life years saved. To demonstrate the usefulness of this method, the risks and benefits of fish consumption are evaluated using a single health risk and health benefit endpoint. Benefits are defined as the decrease in myocardial infarction mortality resulting from fish consumption, and risks are defined as the increase in neurodevelopmental delay (i.e., talking) resulting from prenatal methylmercury exposure. Fish consumption rates are based on information from Washington State. Using the proposed framework, the net health impact of eating fish is estimated in either a whole population or a population consisting of women of childbearing age and their children. It is demonstrated that across a range of fish methylmercury concentrations (0–1 ppm) and intake levels (0–25 g/day), individuals would have to weight the neurodevelopmental effects 6 times more (in the whole population) or 250 times less (among women of child-bearing age and their children) than the myocardial infarction benefits in order to be ambivalent about whether or not to consume fish. These methods can be generalized to evaluate the merits of other public health and risk management programs that involve trade-offs between risks and benefits.

Notes: As part of the launch approval process, the Interagency Nuclear Safety Review Panel provides an independent safety assessment of space missions—such as the Cassini mission—that carry a significant amount of nuclear materials. This survey article describes potential accident scenarios that might lead to release of fuel from an accidental reentry during an Earth swingby maneuver, the probabilities of such scenarios, and their consequences. To illustrate the nature of calculations used in this area, examples are presented of probabilistic models to obtain both the probability of scenario events and the resultant source terms of such scenarios. Because of large extrapolations from the current knowledge base, the analysis emphasizes treatment of uncertainties.