ALBERT

Notes: Recent events have increased awareness of the risk posed by terrorist attacks. Bacillus anthracis has resurfaced in the 21st century as a deadly agent of bioterrorism because of its potential for causing massive civilian casualties. This analysis presents the results of a computer simulation of the dispersion of anthrax spores in a typical 50-story, high-rise building after an intentional release during a bioterrorist incident. The model simulates aerosol dispersion in the case of intensive, small-scale convection, which equalizes the concentration of anthrax spores over the building volume. The model can be used to predict the time interval required for spore dispersion throughout a building after a terrorist attack in a high-rise building. The analysis reveals that an aerosol release of even a relatively small volume of anthrax spores during a terrorist incident has the potential to quickly distribute concentrations that are infectious throughout the building.

Notes: Human health risk assessments use point values to develop risk estimates and thus impart a deterministic character to risk, which, by definition, is a probability phenomenon. The risk estimates are calculated based on individuals and then, using uncertainty factors (UFs), are extrapolated to the population that is characterized by variability. Regulatory agencies have recommended the quantification of the impact of variability in risk assessments through the application of probabilistic methods.In the present study, a framework that deals with the quantitative analysis of uncertainty (U) and variability (V) in target tissue dose in the population was developed by applying probabilistic analysis to physiologically-based toxicokinetic models. The mechanistic parameters that determine kinetics were described with probability density functions (PDFs). Since each PDF depicts the frequency of occurrence of all expected values of each parameter in the population, the combined effects of multiple sources of U/V were accounted for in the estimated distribution of tissue dose in the population, and a unified (adult and child) intraspecies toxicokinetic uncertainty factor UFH-TK was determined.The results show that the proposed framework accounts effectively for U/V in population toxicokinetics. The ratio of the 95th percentile to the 50th percentile of the annual average concentration of the chemical at the target tissue organ (i.e., the UFH-TK) varies with age. The ratio is equivalent to a unified intraspecies toxicokinetic UF, and it is one of the UFs by which the NOAEL can be divided to obtain the RfC/RfD. The 10-fold intraspecies UF is intended to account for uncertainty and variability in toxicokinetics (3.2×) and toxicodynamics (3.2×). This article deals exclusively with toxicokinetic component of UF.The framework provides an alternative to the default methodology and is advantageous in that the evaluation of toxicokinetic variability is based on the distribution of the effective target tissue dose, rather than applied dose. It allows for the replacement of the default adult and children intraspecies UF with toxicokinetic data-derived values and provides accurate chemical-specific estimates for their magnitude. It shows that proper application of probability and toxicokinetic theories can reduce uncertainties when establishing exposure limits for specific compounds and provide better assurance that established limits are adequately protective. It contributes to the development of a probabilistic noncancer risk assessment framework and will ultimately lead to the unification of cancer and noncancer risk assessment methodologies.

Notes: The treatment of uncertainties associated with modeling and risk assessment has recently attracted significant attention. The methodology and guidance for dealing with parameter uncertainty have been fairly well developed and quantitative tools such as Monte Carlo modeling are often recommended. However, the issue of model uncertainty is still rarely addressed in practical applications of risk assessment. The use of several alternative models to derive a range of model outputs or risks is one of a few available techniques. This article addresses the often-overlooked issue of what we call “modeler uncertainty,” i.e., difference in problem formulation, model implementation, and parameter selection originating from subjective interpretation of the problem at hand. This study uses results from the Fruit Working Group, which was created under the International Atomic Energy Agency (IAEA) BIOMASS program (BIOsphere Modeling and ASSessment). Model-model and model-data intercomparisons reviewed in this study were conducted by the working group for a total of three different scenarios. The greatest uncertainty was found to result from modelers' interpretation of scenarios and approximations made by modelers. In scenarios that were unclear for modelers, the initial differences in model predictions were as high as seven orders of magnitude. Only after several meetings and discussions about specific assumptions did the differences in predictions by various models merge. Our study shows that parameter uncertainty (as evaluated by a probabilistic Monte Carlo assessment) may have contributed over one order of magnitude to the overall modeling uncertainty. The final model predictions ranged between one and three orders of magnitude, depending on the specific scenario. This study illustrates the importance of problem formulation and implementation of an analytic-deliberative process in risk characterization.

Notes: This article presents the results of an analysis of the accident history data reported under section 112(r) of the Clean Air Act Amendments. These data provide a fairly complete record of the consequences of reportable accidental releases occurring during the time frame 1995–1999 in the U.S. chemical industry and covering 77 toxic and 63 flammable substances subject to the provisions of section 112(r). As such, these results are of fundamental interest to the affected communities, regulators, and insurers, as well as to owners and managers in the chemical industry. The results show the statistical associations between accident frequency and severity and a number of characteristics of reporting facilities, including their size, the hazardousness of the processes and chemicals inventoried, and the regulatory programs (in addition to section 112(r)) to which these facilities are subject. The results are interpreted in light of economic drivers of protective activity and regulatory priorities for monitoring and enforcement.

Notes: Unlike other waste streams, municipal solid waste (MSW) is collected manually, and MSW collection has recently been found to be among the highest-risk occupations in the United States. However, as for other occupational groups, actual total injury rates, including the great majority of injuries not compensated and those compensated by other insurance, are not known. In this article a predictive Bayesian method of assessing total injury rates from available information without computation is presented, and used to assess the actual numbers of musculoskeletal and dermal injuries requiring clinical care of MSW workers in Florida. Closed-form predictive Bayesian distributions that narrow progressively in response to information, representing both uncertainty and variability, are presented. Available information included workers' compensation (WC) data, worker population data, and safety records for one private and one public collection agency. Subjective input comprised epidemiological and medical judgment based on a review of 165 articles. The number of injuries was assessed at 3,146 annually in Florida, or 54 ± 18 injuries per 100 workers per year with 95% confidence. Further, WC data indicate that the injury rate is 50% higher for garbage collectors specifically, indicating a rate of approximately 80 per 100 workers. Results, though subject to uncertainty in worker numbers and classification and reporting bias, agreed closely with a survey of 251 MSW collectors, of whom 75% reported being injured (and 70% reported illness) within the past 12 months. The approach is recommended for assessment of total injury rates and, where sufficient information exists, for the more difficult assessment of occupational disease rates.

Notes: Statistical fatigue life of a ductile alloy specimen is traditionally divided into three stages, namely, crack nucleation, small crack growth, and large crack growth. Crack nucleation and small crack growth show a wide variation and hence a big spread on cycles versus crack length graph. Relatively, large crack growth shows a lesser variation. Therefore, different models are fitted to the different stages of the fatigue evolution process, thus treating different stages as different phenomena. With these independent models, it is impossible to predict one phenomenon based on the information available about the other phenomenon. Experimentally, it is easier to carry out crack length measurements of large cracks compared to nucleating cracks and small cracks. Thus, it is easier to collect statistical data for large crack growth compared to the painstaking effort it would take to collect statistical data for crack nucleation and small crack growth. This article presents a fracture mechanics-based stochastic model of fatigue crack growth in ductile alloys that are commonly encountered in mechanical structures and machine components. The model has been validated by Ray (1998) for crack propagation by various statistical fatigue data. Based on the model, this article proposes a technique to predict statistical information of fatigue crack nucleation and small crack growth properties that uses the statistical properties of large crack growth under constant amplitude stress excitation. The statistical properties of large crack growth under constant amplitude stress excitation can be obtained via experiments.

Notes: An occupational risk assessment for manganese (Mn) was performed based on benchmark dose analysis of data from two epidemiological studies providing dose-response information regarding the potential neurological effects of exposure to airborne Mn below the current Occupational Safety and Health Administration (OSHA) Permissible Exposure Level (PEL) of 5 mg Mn/m3. Based on a review of the scientific evidence regarding the toxicity of Mn, it was determined that the most appropriate measure of exposure to airborne Mn for the subclinical effects measured in these studies is recent (rather than historical or cumulative) concentration of Mn in respirable (rather than total) particulate. For each of the studies analyzed, the individual exposure and response data from the original study had been made available by the investigators. From these two studies benchmark concentrations calculated for eight endpoints ranged from 0.09 to 0.27 mg Mn/m3. From our evaluation of these results, and considering the fact that the subtle, subclinical effects represented by the neurological endpoints tested in these studies do not represent material impairment, we believe an appropriate occupational exposure guideline for manganese would be in the range of 0.1 to 0.3 mg Mn/m3, based on the respirable particulate fraction only, and expressed as an 8-hour time-weighted average.

Notes: The Safe Drinking Water Act Amendments of 1996 required U.S. utilities to report on drinking water quality to their customers annually, beginning in fall 1999, on the assumption that such reports would alert them to quality problems and perhaps mobilize pressure for improvement. A random sample of New Jersey customers read alternative versions of a water quality report, in an experiment on reactions to water quality information under U.S. Environmental Protection Agency (USEPA) rules. Experiment design was 2 × 3 + 1: two versions each—one with, one without, a violation of a health standard—of a report that was (1) Qualitative (without water quality numbers, thus not meeting USEPA rules); (2) Basic, with minimal information meeting the rules; or (3) Extended, adding reading aids and utility performance information; plus a control instrument without any hypothetical report. Results of ANOVA suggest the reports will have less effect than hoped or feared. These manipulations were successful: people reading the Qualitative versions were less likely to say that the report gave the amounts of substances found in the water, and those reading Violation versions were more likely to report a violation of a health standard. The main differences in responses to the report involved the judged adequacy of the information, and to a lesser extent responses on a Concern scale (constructed from measures of concern, judged risk, clean-up intentions, distrust of utility information, and doubt that the utility was doing all it could to improve water quality). Overall judgments of water quality and utility performance did not change, either relative to the controls or in before versus after responses. Qualitative reports performed worse than others, confirming the decision to have utilities report actual contaminant levels. Extended reports did only slightly better than the Basic versions on these measures. Many respondents had trouble identifying the presence or absence of substance amounts or violations, despite their seeming obviousness (e.g., in a “bottom line” summary on the front page of each report), suggesting many were not processing this information carefully. However, the pattern of responses for those who accurately identified the presence or absence of substance amounts or violations did not differ substantially from that for the group as a whole. Generic risk beliefs (serious local environmental problems; lack of control over risks to one's health) dominated demographic variables, attitudes toward utility water quality or trustworthiness, and the content and format of water quality reports in influencing concern about drinking water quality. Previous empirical and theoretical evidence for lack of change in public risk attitudes due to one-time or infrequent communications—e.g., role of personal experience, perseverance of prior trust or distrust—seems to be confirmed for annual water quality reports.

Notes: Polluted soils have become a public health problem. While population exposure to soil pollutants is generally quantified using multimedia models, their estimations have not been validated, and studies that attempted to do so are scarce. The objective of the SOLEX study was to compare the predictions of pyrene exposure levels (converted into 1 hydroxypyrene) computed by several models with the results of urinary 1-hydropyrene (1-HOP) assays among 110 employees working at three sites polluted during their past use as manufactured gas plants. Four models were used: AERIS (Canada), CalTOX (California, USA), CLEA (UK), and HESP (The Netherlands). Three occupational exposure scenarios—with office, mixed, and outdoor workers—were constructed, based upon job activities during two measurement campaigns, one in winter and one in summer. The exposure levels estimated by the four models could differ markedly (from 7 up to 80 times) according to the exposure scenario. Also, the predominant exposure routes differed according to the model (direct soil ingestion for HESP and CalTOX, inhalation for AERIS, and dermal absorption for CLEA). The predictions of CalTOX are consistent with the 1-HOP measurements for all the scenarios. For HESP, the consistency is observed for the scenarios, office and mixed, for which the pyrene level in the soil is low. AERIS and CLEA yield results that are systematically above the 1-HOP measurements. This study confirms that validation of the models is crucial and points out to the need to proceed to assess components of the models that are the most influential using appropriate statistical analysis in combination with true field data.

Notes: The wide-scale use of methyl tertiary butyl ether (MTBE) in gasoline has resulted in substantial public controversy and action to ban or control its use due to perceived impacts on water quality. Because oxygenates are still required under federal law, considerable research has focused on ethanol as a substitute for MTBE. In this article, we summarize the currently available literature on the air and water quality risks and benefits of MTBE versus ethanol as alternative fuel oxygenates. We find that MTBE-fuel blends are likely to have substantial air quality benefits; ethanol-fuel blends appear to offer similar benefits, but these may be at least partially negated because of ethanol's propensity to increase emissions and ambient concentrations of some air contaminants. Releases of gasoline containing either MTBE or ethanol could have an impact on some drinking water sources, although the impacts associated with MTBE tend to relate to aesthetics (i.e., taste and odor), whereas the impacts associated with ethanol generally relate to health risk (i.e., greater exposure to gasoline constituents such as benzene). It is likely that these water quality impacts will be outweighed by the air quality benefits associated with MTBE and perhaps ethanol use, which affect a much larger population. A lack of data on environmental exposures and associated health impacts hinders the completion of a comprehensive quantitative risk-benefit analysis, and the available air and water quality data should be evaluated in a broader risk-management context, which considers the potential life-cycle impacts, costs, and feasibility associated with alternative fuel oxygenates.

Notes: A sample of 3,201 Danes was subjected to personal interviews in which they were asked to state their preferences for risk-reducing health care interventions based on information on absolute risk reduction (ARR) and relative risk reduction (RRR). The aim of the study was to measure the relative weighting of different types of risk information under various circumstances. The effect of presenting questions, and of explicitly formulating RRR, was analyzed. A preference for increases in RRR was demonstrated. There was a stronger inclination to choose the intervention that offered the highest RRR if RRR was explicitly stated. Individuals with more than 10 years of schooling also demonstrated a preference for increased ARR, but only when facing individually framed choices. In a social choice context, preferences for RRR remained intact, but the magnitude of ARR had no impact on choices. Results imply that social framing may induce a propensity to prefer interventions that target high-risk populations. Those respondents who had received ≤10 years of schooling demonstrated preferences for RRR but not ARR, and no impact of social framing was observed.

Notes: The relationship between trust and risk perception was investigated, within and across four European countries (Sweden, Spain, United Kingdom, and France). Survey data were collected in 1996; total number of respondents was approximately 1,000 (United Kingdom and Spain), 1,350 (France), and 2,050 (Sweden). Trust was a significant predictor of perceived risk within countries, but the strength of the relationship varied from weak (Spain and France) to moderate (United Kingdom and Sweden). General trust was also a significant source of variation in perceived risk among countries, but much of the variation in perceived risk remained unexplained. Correlations between trust and risk perception also varied depending on the type of risk (i.e., nuclear risks were more influenced by trust) and trust measure (i.e., general trust explained perceived risk better than specific trust). It is concluded that trust may be an element in models explaining risk perception, but it is not as powerful as often argued in the risk perception literature.

Notes: Despite many claims for and against the use of risk comparisons in risk communication, few empirical studies have explored their effect. Only one study, published by Roth et al. in this journal in 1990, has tested the 1988 predictions by Covello et al. as to the public's relative preferences for 14 kinds of risk comparisons as they might be used by a factory manager to explain risks of his ethylene oxide plant. That study found no correlations between the Covello predictions and seven different measures of “acceptability” of Covello's examples of each type of comparison. However, two critics of the Roth study, as well as its own authors, suggested that a scenario involving local risks, a conflict-ridden situation, and a plant manager unknown to the townspeople might better evoke Covello-like preferences than the distant, calm, friends-involving scenario used by Roth. The research reported here replicated the Roth study using the same scenario, risk comparison examples, and evaluation measures, and added a second scenario intended to replicate the conditions suggested by critics. Over 200 New Jersey residents answered the study questionnaire. The replication scenario reproduced Roth's results, and the conflict scenario also evoked no rankings correlated with Covello's predictions. Furthermore, neither agreement nor disagreement with five statements representing “conflict”—respondents' reports that the industrial-plant scenario made them angry, they lived near industry, they were concerned about industrial risks, people in their home town were angry about industrial pollution, and they worried “frequently” about long-term effects of pollution—correlated with Covello's predictions. Over half of all ratings ascribed to the comparisons in aggregate were positive, and most detailed comments offered by respondents also were positive, despite many criticisms and suggestions for their improvement. The wide variability in individuals' rankings also undermines the notion of any single ranking of preferred comparisons. These findings have implications for use of risk comparisons, but also reveal the inaccuracy of the field's assumptions about public reaction to industrial risk information, including risk comparison.

Notes: The effect of specification of the target on risk evaluation was examined. A whole set of hazards, covering most of the domains, were considered: common individual hazards, outdoor activities, medical care, public transportation, energy production, pollutants, sex, deviance, and addictions. Three human targets were introduced: personal health risk (including personal risk of death), health risk for people in the country, and health risk for people in the world. The basic design was a between-subjects design. The first hypothesis was that risk judgments made in the “world” condition should be higher than risk judgments made in the “country” condition, and risk judgments made in this condition should be higher than risk judgments made in the “personal” condition. This is what was observed. The second hypothesis was that the target effect should differ as a function of the kind of hazards considered. This also is what was observed. In two domains— pollutants, and deviance, sex, and addictions—the target effect was important. It corresponded to about one-tenth of the response scale. In the four remaining domains, the target effect was unimportant or absent.

Notes: Dissemination of risk information is ubiquitous in contemporary society. We explore how individuals react in everyday life to health-risk information, based on what they report in personal interviews. Health-risk information was without exception recognized as unstable and inconsistent. This conformity, however, did not extend to the narratives regarding how health-risk information should be handled. Two opposite positions (ideal-typical strategies) are presented. Either you tend to process and evaluate new information or you tend to ignore it as a whole. Our attempt to reveal the underlying rationality in these two very different approaches involved the exploration of three different avenues of interpretation and brings together two scientific paradigms—economics and sociology—that provide the framework for our analysis. First, we suggest that a greater long-term experience of explicit choice implies that this kind of action becomes more natural and less resource consuming, whereas a reliance on habits in daily life—a natural adjustment to a lack of resources—makes it is more costly to bother about new information. Second, with fewer resources in the short run, fewer opportunities to mitigate bad outcomes, and greater exposure to social and material risks, one is less likely to devote resources to deal with health-risk information. Third, there are several possible links between a low propensity to take account of risk information and a high relative importance of genuine uncertainty in one's life. These theoretical perspectives provide a viable set of hypotheses regarding mechanisms that may contribute to social differences in the response to health-risk information.

Notes: European directives require that all veterinary medicines be assessed to determine the harmful effects that their use may have on the environment. Fundamental to this assessment is the calculation of the predicted environmental concentration (PEC), which is dependent on the type of drug, its associated treatment characteristics, and the route by which residues enter the environment. Deterministic models for the calculation of the PEC have previously been presented. In this article, the inclusion of variability and uncertainty within such models is introduced. In particular, models for the calculation of the PEC for residues excreted directly onto pasture by grazing animals are considered and comparison of deterministic and stochastic results suggest that uncertainty and variability cannot be ignored.

Notes: In risk assessment, no observed exposure level (NOAEL) and benchmark dose (BMD) are usually derived either from epidemiological studies in humans or from animal experiments. In many in vitro studies, concentration-effect/response curves have been analyzed using different mathematical models finalized to the identification of EC50. In the present article, we propose a model to fit dose-response curves in vitro. The BMD approach has been used to compare the cell viability (MTT assay) of different rat (C6 and PC12, glial and neuronal, respectively) and human cell lines (D384 and SK-N-MC, glial and neuronal, respectively) after 24-hour exposure to the following neurotoxic substances: manganese chloride (MnCl2), methyl-mercury (Me-Hg), and the enantiomers of styrene oxide (SO). For all rat and human cell lines, the potency of the examined compounds was: MnCl2 〈 S-SO 〈 R-SO 〈 Me-Hg. A preliminary comparison with in vivo toxicity data for these substances gave rise to consistent results. Whereas a reasonable agreement between in vitro and in vivo data has been found for Mn and styrene oxide, a wide scatter of LOAEL has been reported for Me-Hg and these appear to be either much higher or lower than the BMD for the MTT assay we observed invitro.

Notes: This article examines the role of climatic and hydrological variability in assessing the cumulative risk of flood events in Poland over a T-year period. In a broad sense flood-risk estimation combines a frequency analysis of extreme hydrological phenomena with an evaluation of flood-induced damages. The damage from floods depends on the critical values of the river discharges. The probabilistic flood analysis usually includes an estimation of the expected annual probability of the critical discharge Qcr being exceeded and the equivalent long-term risk of it being exceeded over the next T years. If, however, the process is nonstationary, the T-year risk of flood damage may depend importantly on the variation of hydrological processes. As a possible explanation for the variations observed in snowmelt-induced floods in Polish rivers, this article investigates the possible impact of the North Atlantic Oscillation (NAO) on surface air temperature T and precipitation P. The spatial distribution of the correlation coefficients between NAO and T, as well as NAO and P, show very significant differences in the NAO impact on meteorological variables in various parts of Europe. To assess the implications of NAO variations on spring flood discharges, a simple model of Snow Cover Water Equivalent (SCWE) was applied to selected Polish river catchments. The conclusion of this analysis is that the yearly maximum of SCWE values significantly decreases with increasing NAO. This leads to a temporal redistribution of winter and spring runoff. The question of spring flood characteristics being stationary or nonstationary may therefore be linked with stochastic properties of the NAO index time series.

Notes: We examine the opportunities for using catastrophe-linked securities (or equivalent forms of nondebt contingent capital) to reduce the total costs of funding infrastructure projects in emerging economies. Our objective is to elaborate on methods to reduce the necessity for unanticipated (emergency) project funding immediately after a natural disaster. We also place the existing explanations of sovereign-level contingent capital into a catastrophic risk management framework. In doing so, we address the following questions. (1) Why might catastrophe-linked securities be useful to a sovereign nation, over and above their usefulness for insurers and reinsurers? (2) Why are such financial instruments ideally suited for protecting infrastructure projects in emerging economies, under third-party sponsorship, from low-probability, high-consequence events that occur as a result of natural disasters? (3) How can the willingness to pay of a sovereign government in an emerging economy (or its external project sponsor), who values timely completion of infrastructure projects, for such instruments be calculated? To supplement our treatment of these questions, we use a multilayer spreadsheet-based model (in Microsoft Excel format) to calculate the overall cost reductions possible through the judicious use of catastrophe-based financial tools. We also report on numerical comparative statics on the value of contingent-capital financing to avoid project disruption based on varying costs of capital, probability and consequences of disasters, the feasibility of strategies for mid-stage project abandonment, and the timing of capital commitments to the infrastructure investment. We use these results to identify high-priority applications of catastrophe-linked securities so that maximal protection can be realized if the total number of catastrophe instruments is initially limited. The article concludes with potential extensions to our model and opportunities for future research.

Notes: Risk perceptions have, to a great extent, been studied exclusively as individual cognitive mechanisms in which individuals collect, process, and form perceptions as atomized units unconnected to a social system. These individual-level theories do not, however, help explain how perception of risk may vary between communities or within a single community. One alternative approach is based on a network theory of contagion. This approach, emerging largely from organizational and community social network studies, suggests that it is the relational aspects of individuals and the resulting networks and self-organizing systems that influence individual perceptions and build “groups or communities of like-minded” individuals. These social units, it is argued, behave as attitude, knowledge, or behavioral structures. The study reported in this article tests one aspect of this theoretical perspective. The central hypothesis proposes the existence of risk perception networks—relational groupings of individuals who share, and perhaps create, similar risk perceptions. To test this idea, data were collected from individuals involved in a community environmental conflict over a hazardous waste site cleanup. The statistical analysis used a matrix of relational social linkages to compare with a matrix of individual risk perceptions. The analysis confirmed the hypothesis suggesting that social linkages in communities may play an important role in focusing risk perceptions.

Notes: We adopted a comparative approach to evaluate and extend a generic methodology to analyze the different sets of beliefs held about chemical hazards in the workplace. Our study mapped existing knowledge structures about the risks associated with the use of perchloroethylene and rosin-based solder flux in differing workplaces. “Influence diagrams” were used to represent beliefs held by chemical experts; “user models” were developed from data elicited from open-ended interviews with the workplace users of the chemicals. The juxtaposition of expert and user understandings of chemical risks enabled us to identify knowledge gaps and misunderstandings and to reinforce appropriate sets of safety beliefs and behavior relevant to chemical risk communications. By designing safety information to be more relevant to the workplace context of users, we believe that employers and employees may gain improved knowledge about chemical hazards in the workplace, such that better chemical risk management, self-protection, and informed decision making develop over time.

Notes: Seven driving attitude scales representing driving behaviors and beliefs about driving were created and initially validated using 257 undergraduate students (168 females, 89 males) in Study 1. However, the Speeding Attitude Scale (SAS) accounted for most of the strength of the intercorrelations among these scales and discriminant classification analyses showed that SAS dominated the other scales as a sufficient explanation for having speeding tickets. Study 2, using 180 students (75 males, 105 females), replicated findings regarding the significant but low correlation between SAS and speeding tickets, and was significantly correlated with Zuckerman's Sensation Seeking Scale (SSS). Replication also showed that males had higher SAS scores and more speeding tickets. Accidents were typically a function of sex, increasing age, and variables related to recent accident history. Objective sources of speeding attitude confirmation may enhance the future validity of the SAS. Potential interventions for being a safe passenger and attitudinal control in the training of young drivers were discussed.

Notes: The prospect of industrial accidents motivated the U.S. Congress to require in the Clean Air Act of 1990 that manufacturing facilities develop Risk Management Plans (RMP) to submit to the U.S. Environmental Protection Agency (USEPA) by July 1999. Industry worried that the requirement to communicate to the public a “worst-case scenario” would arouse unnecessary and counterproductive fears among industry neighbors. We report here the results of focus groups and surveys with such neighbors, focusing particularly upon their reactions to messages about a hypothetical worst-case scenario and management of these risks by industry, government, and other parties. Our findings confirmed our hypotheses that citizens would be skeptical of the competence and trustworthiness of these managers and that this stance would color their views of industrial-facility accident risks. People with job ties to industry or who saw industrial benefits to the community as exceeding its risks had more positive views of industrial risks, but still expressed great concern about the risk and doubt about accident management. Notwithstanding these reactions, overall respondents welcomed this and other related information, which they wanted their local industries to supply. Respondents were not more reassured by additional text describing management of accidents by government and industry. However, respondents did react very positively to the concept of community oversight to review plant safety. Claims about the firm's moral obligation or financial self-interest in preventing accidents were also received positively. Further research on innovative communication and management of accident risks is warranted by these results, even before recent terrorist attacks made this topic more salient.

Notes: Enabling people to make an informed choice on whether to change consumption behavior is ultimately the objective of any fish consumption advisory. This will occur only if people are aware of the advisory, know and understand the advisory information, and believe the information to be true. Interactive, meaningful communication and the opportunity to participate in the process to develop and review advisories are key to achieving these attributes. A case study was undertaken in a community in Alberta, Canada (where an existing advisory was under consideration for review) to determine public awareness, knowledge, compliance, communication effectiveness, information needs, and desire for involvement related to the advisory. The information obtained from this case study was used to develop 14 guiding principles as a foundation for the incorporation of public participation and risk communication into the process of developing and reviewing fish consumption advisories.

Notes: The impacts of fish consumption advisories on recreational and subsistence fishing, particularly in fresh waters, have been examined extensively. By contrast, little attention has focused on organized recreational fishing, such as from party and charter boats, and particularly for salt water fish. We interviewed 93 New Jersey boat captains to determine their knowledge about fish consumption advisories, and whether, in their opinion, clients knew of fish consumption advisories, and whether they thought advisories had an effect on recreational fishing and their businesses. Advisories were ranked by captains as a moderate influence on the success of their business, less so than number of fish caught, strength of the economy, overfishing by commercial boats, and management regulations. Only one boat captain had not heard warnings about eating fish, but what captains said they had heard was mixed in its accuracy and completeness. Clients expect captains to know about fish, and about half of boat captains said clients had asked about the safety of eating fish. Captains who felt advisories were affecting their businesses tended to fish for species without high levels of mercury (except for bluefish) or PCBs, the primary contaminants of concern for state advisories and federal advice. However, these captains worked closer to areas (e.g., Raritan Bay complex and New York Harbor) subject to advisories than did other captains, and were more prone to say that management regulations (e.g., fish size, creel limits, seasons) and marketing and advertising by the industry or state were strong influences on the success of their seasons. Comparing captains who thought advisories had some or great effect (60%) versus those reporting “no effect” (40%), there was no difference in the mean percentage of trips targeting high mercury species such as swordfish and shark. Many captains said they would or might post advisories, but 42% of the boat captains said they would not post consumption warnings if the state provided them. The significant portion (at least 15%) of saltwater fishing supported by these businesses suggests that these captains are an important conduit for future risk communication.

Notes: This article begins with a review of the regulation of chemicals in Sweden over the past 30 years, focusing particularly on the 1997 Government Environmental Quality Bill, which called for a toxic-free society by the year 2020. The second part of the article analyzes why Sweden has taken this route. The third and final section discusses Sweden's present role in formulating present EU chemical regulation, such as the recent EU Chemical White Paper, and hypothesizes future impacts of Swedish chemical regulations on the EU itself.

Notes: In 2001, the U.S. Environmental Protection Agency derived a reference dose (RfD) for methylmercury, which is a daily intake that is likely to be without appreciable risk of deleterious effects during a lifetime. This derivation used a series of benchmark dose (BMD) analyses provided by a National Research Council (NRC) panel convened to assess the health effects of methylmercury. Analyses were performed for a number of endpoints from three large longitudinal cohort studies of the neuropsychological consequences of in utero exposure to methylmercury: the Faroe Islands, Seychelles Islands, and New Zealand studies. Adverse effects were identified in the Faroe Islands and New Zealand studies, but not in the Seychelles Islands. The NRC also performed an integrative analysis of all three studies. The EPA applied a total uncertainty factor (UF) of 10 for intrahuman toxicokinetic and toxicodynamic variability and uncertainty. Dose conversion from cord blood mercury concentrations to maternal methylmercury intake was performed using a one-compartment model. Derivation of potential RfDs from a number of endpoints from the Faroe Islands study converged on 0.1 μg/kg/day, as did the integrative analysis of all three studies. EPA identified several areas for which further information or analyses is needed. Perhaps the most immediately relevant is the ratio of cord:maternal blood mercury concentration, as well as the variability around this ratio. EPA assumed in its dose conversion that the ratio was 1.0; however, available data suggest it is perhaps 1.5–2.0. Verification of a deviation from unity presumably would be translated directly into comparable reduction in the RfD. Other areas that EPA identified as significant areas requiring further attention are cardiovascular consequences of methylmercury exposure and delayed neurotoxicity during aging as a result of previous developmental or adult exposure.

Notes: Risk estimates for food-borne infection will usually depend heavily on numbers of microorganisms present on the food at the time of consumption. As these data are seldom available directly, attention has turned to predictive microbiology as a means of inferring exposure at consumption. Codex guidelines recommend that microbiological risk assessment should explicitly consider the dynamics of microbiological growth, survival, and death in foods. This article describes predictive models and resources for modeling microbial growth in foods, and their utility and limitations in food safety risk assessment. We also aim to identify tools, data, and knowledge sources, and to provide an understanding of the microbial ecology of foods so that users can recognize model limits, avoid modeling unrealistic scenarios, and thus be able to appreciate the levels of confidence they can have in the outputs of predictive microbiology models. The microbial ecology of foods is complex. Developing reliable risk assessments involving microbial growth in foods will require the skills of both microbial ecologists and mathematical modelers. Simplifying assumptions will need to be made, but because of the potential for apparently small errors in growth rate to translate into very large errors in the estimate of risk, the validity of those assumptions should be carefully assessed. Quantitative estimates of absolute microbial risk within narrow confidence intervals do not yet appear to be possible. Nevertheless, the expression of microbial ecology knowledge in “predictive microbiology” models does allow decision support using the tools of risk assessment.

Notes: Monte Carlo simulation has become the accepted method for propagating parameter uncertainty through risk models. It is widely appreciated, however, that correlations between input variables must be taken into account if models are to deliver correct assessments of uncertainty in risk. Various two-stage methods have been proposed that first estimate a correlation structure and then generate Monte Carlo simulations, which incorporate this structure while leaving marginal distributions of parameters unchanged. Here we propose a one-stage alternative, in which the correlation structure is estimated from the data directly by Bayesian Markov Chain Monte Carlo methods. Samples from the posterior distribution of the outputs then correctly reflect the correlation between parameters, given the data and the model. Besides its computational simplicity, this approach utilizes the available evidence from a wide variety of structures, including incomplete data and correlated and uncorrelated repeat observations. The major advantage of a Bayesian approach is that, rather than assuming the correlation structure is fixed and known, it captures the joint uncertainty induced by the data in all parameters, including variances and covariances, and correctly propagates this through the decision or risk model. These features are illustrated with examples on emissions of dioxin congeners from solid waste incinerators.

Notes: Precautionary behavior serves a valuable protective purpose as a first response to the new. It causes a quick retreat to the safety of the familiar; it provides time for a realistic “friend or foe” assessment of a new event. This rational assessment is often delayed by the sluggishness of government bureaucratic processes, or stopped by an implied challenge to a status quo. At the public level, reassurance may be slow to overcome an early uncertainty. However, a precautionary response does not provide an operational governing principle, although it makes publicly plausible an indefinite concealment of de facto political actions, or nonaction. The alternative of rational decision making at the policy level should flow from a comparative benefit/cost/risk analysis. Such early risk analyses have pragmatic uncertainties based on the limited available knowledge base and, accordingly, require judgmental application.

Notes: The joint persistence (JP) quantifies the environmental persistence of a parent compound and a selection of relevant transformation products. Here, the importance as well as the uncertainty of the JP in comparison to the persistence of the parent compound alone (primary persistence, PP) are investigated. To demonstrate the effect of transformation products on the environmental persistence of organic chemicals, three case studies of parent compounds (nonylphenol ethoxylates, perchloroethylene, atrazine) and transformation products are investigated in detail with a multimedia fate model. Comparison of the PP and JP values shows that transformation products can significantly increase the persistence. In addition to the point estimates of PP and JP, the associated uncertainties are investigated. For each of the case studies, the chemical-specific input parameters of all compounds are varied and the corresponding variance of the PP and JP is determined by Monte Carlo simulations. Interestingly, the higher number of input parameters required for the JP does not necessarily increase the uncertainty of the JP as compared to that of the PP alone. An exact mathematical expression specifying the contribution of each transformation product to the JP is given. When transformation products are grouped in different generations, it becomes discernible that the first generation increases the JP most; the later generations are of decreasing importance. Finally, the effect of incomplete knowledge of the transformation products and their properties on the JP results is discussed. For reliable JP estimates, knowledge of the first generation transformation products and their degradation rate constants is required.

Notes: Physicians are increasingly asked to use cost-effectiveness information when evaluating alternative health care interventions. Little is known about how the way such information is presented can influence medical decision making. We presented physicians with hypothetical screening scenarios with multiple options, varying the type of cost-effectiveness ratios provided as well as whether the scenarios described cancer screening settings that were familiar or unfamiliar. Half the scenarios used average cost-effectiveness ratios, as commonly reported, calculating benefits and costs relative to a no-screening option. The other half used the preferred incremental cost-effectiveness ratios, with each option's benefits and costs calculated relative to the next best alternative. Relative to average cost-effectiveness ratios, incremental cost-effectiveness information significantly reduced preference for the most expensive screening strategies in two of three unfamiliar scenarios. No such difference was found for familiar scenarios, for which physicians likely have established practice patterns. These results suggest that, in unfamiliar settings, average cost-effectiveness ratios as reported in many analyses reported in the literature can hide the often high price for achieving incremental health care goals, potentially causing physicians to choose interventions with poor cost effectiveness.

Notes: In earlier work we assembled a database of classical pharmacokinetic parameters (e.g., elimination half-lives; volumes of distribution) in children and adults. These data were then analyzed to define mean differences between adults and children of various age groups. In this article, we first analyze the variability in half-life observations where individual data exist. The major findings are as follows. The age groups defined in the earlier analysis of arithmetic mean data (0–1 week premature; 0–1 week full term; 1 week to 2 months; 2–6 months; 6 months to 2 years; 2–12 years; and 12–18 years) are reasonable for depicting child/adult pharmacokinetic differences, but data for some of the earliest age groups are highly variable. The fraction of individual children's half-lives observed to exceed the adult mean half-life by more than the 3.2-fold uncertainty factor commonly attributed to interindividual pharmacokinetic variability is 27% (16/59) for the 0–1 week age group, and 19% (5/26) in the 1 week to 2 month age group, compared to 0/87 for all the other age groups combined between 2 months and 18 years. Children within specific age groups appear to differ from adults with respect to the amount of variability and the form of the distribution of half-lives across the population. The data indicate departure from simple unimodal distributions, particularly in the 1 week to 2 month age group, suggesting that key developmental steps affecting drug removal tend to occur in that period. Finally, in preparation for age-dependent physiologically-based pharmacokinetic modeling, nationally representative NHANES III data are analyzed for distributions of body size and fat content. The data from about age 3 to age 10 reveal important departures from simple unimodal distributional forms—in the direction suggesting a subpopulation of children that are markedly heavier than those in the major mode. For risk assessment modeling, this means that analysts will need to consider “mixed” distributions (e.g., two or more normal or log-normal modes) in which the proportions of children falling within the major versus high-weight/fat modes in the mixture changes as a function of age. Biologically, the most natural interpretation of this is that these subpopulations represent children who have or have not to yet received particular signals for change in growth pattern. These apparently distinct subpopulations would be expected to exhibit different disposition of xenobiotics, particularly those that are highly lipophilic and poorly metabolized.

Notes: Three topics are addressed: (1) measurement issues (e.g., the reliability and validity of neurobehavioral test scores), (2) general principles of assessment, including test selection, and (3) interpretation of scores. Psychological tests generally perform as well as medical tests in terms of reliability and validity. Test manuals, assessment textbooks, and psychologists are useful resources to the risk assessor. The variety of different tests employed in neurobehavioral studies complicates interstudy comparisons. In addition, tests that ostensibly assess the same general domain of function might assess somewhat different abilities within that domain. Although a uniform battery for use in all studies seems desirable, the battery appropriate for a specific study depends on study goals, knowledge about the mechanism(s) of neurotoxicity, nature of the study population, and pattern of exposure. Exposure-related neurobehavioral deficits are generally indicators of “altered function” rather than of “clinical disease.” Limiting concern to end points corresponding to clinical disease might not be appropriate. Many neurobehavioral diagnoses are phenomenological and a neurotoxicant might cause a unique pattern of deficits for which no label has been created. The concern that a small shift in the central tendency of a distribution of test scores has no significance for the individual should be reexamined in light of the prevention paradox, formulated on the basis of epidemiologic studies of chronic disease. Poor performance on a neurobehavioral test does not necessarily map clearly onto underlying behavioral or neural substrate. The absence of such linkages, given current knowledge about brain-behavior relationships, should not reduce confidence in neurobehavioral end points. Use of neurobehavioral test scores involves considerations that differ little from those that the risk assessor routinely addresses in using end points commonly used in research on other topics in environmental epidemiology.

Notes: Health care professionals are a major source of risk communications, but their estimation of risks may be compromised by systematic biases. We examined fuzzy-trace theory's predictions of professionals' biases in risk estimation for sexually transmitted infections (STIs) linked to: knowledge deficits (producing underestimation of STI risk, re-infection, and gender differences), gist-based mental representation of risk categories (producing overestimation of condom effectiveness for psychologically atypical but prevalent infections), retrieval failure for risk knowledge (producing greater risk underestimation when STIs are not specified), and processing interference involving combining risk estimates (producing biases in post-test estimation of infection, regardless of knowledge). One-hundred-seventy-four subjects (experts attending a national workshop, physicians, other health care professionals, and students) estimated the risk of teenagers contracting STIs, re-infection rates for males and females, and condom effectiveness in reducing infection risk. Retrieval was manipulated by asking estimation questions in two formats, a specific format that “unpacked” the STI category (infection types) and a global format that did not provide specific cues. Requesting estimates of infection risk after relevant knowledge was directly provided, isolating processing effects, assessed processing biases. As predicted, all groups of professionals underestimated the risk of STI transmission, re-infection, and gender differences, and overestimated the effectiveness of condoms, relative to published estimates. However, when questions provided better retrieval supports (specified format), estimation bias decreased. All groups of professionals also suffered from predicted processing biases. Although knowledge deficits contribute to estimation biases, the research showed that biases are also linked to fuzzy representations, retrieval failures, and processing errors. Hence, interventions that are designed to improve risk perception among professionals must incorporate more than knowledge dissemination. They should also provide support for information representation, effective retrieval, and accurate processing.

Notes: The adverse impacts of particulate air pollution and ground-level ozone on public health and the environment have motivated the development of Canada Wide Standards (CWS) on air quality. In cost-benefit analysis of air-quality options, valuation of reduction in mortality is a critical step as it accounts for almost 80% of the total benefits and any bias in its evaluation can significantly skew the outcome of the analysis. The overestimation of benefits is a source of concern since it has the potential of diverting valuable resources from other needs to support broader health care objectives, education, and social services that contribute to enhanced quality of life. We have developed a framework of reasoning for the assessment of risk-reduction initiatives that would support the public interest and enhance safety and quality of life. This article presents the Life Quality Index (LQI) as a tool to quantify the level of expenditure beyond which it is no longer justifiable to spend resources in the name of safety. It is shown that the LQI is a compound social indicator comprising societal wealth and longevity, and it is also equivalent to a utility function consistent with the basic principles of welfare economics and decision analysis. The LQI approach overcomes several shortcomings of the method used by the CWS Development Committee and provides guidance on the compliance costs that can be justified to meet the Standards.

Notes: There is increasing interest in the integration of quantitative risk analysis with benefit-cost and cost-effectiveness methods to evaluate environmental health policy making and perform comparative analyses. However, the combined use of these methods has revealed deficiencies in the available methods, and the lack of useful analytical frameworks currently constrains the utility of comparative risk and policy analyses. A principal issue in integrating risk and economic analysis is the lack of common performance metrics, particularly when conducting comparative analyses of regulations with disparate health endpoints (e.g., cancer and noncancer effects or risk-benefit analysis) and quantitative estimation of cumulative risk, whether from exposure to single agents with multiple health impacts or from exposure to mixtures. We propose a general quantitative framework and examine assumptions required for performing analyses of health risks and policies. We review existing and proposed risk and health-impact metrics for evaluating policies designed to protect public health from environmental exposures, and identify their strengths and weaknesses with respect to their use in a general comparative risk and policy analysis framework. Case studies are presented to demonstrate applications of this framework with risk-benefit and air pollution risk analyses. Through this analysis, we hope to generate discussions regarding the data requirements, analytical approaches, and assumptions required for general models to be used in comparative risk and policy analysis.

Notes: A quantitative risk analysis was conducted to evaluate the design of the VX neutralization subsystem and related support facilities of the U.S. Army Newport Chemical Agent Disposal Facility. Three major incidents including agent release, personnel injury, and system loss were studied using fault tree analysis methodology. Each incident was assigned a risk assessment code based on the severity level and probability of occurrence of the incident. Safety mitigations or design changes were recommended to bring the “undesired” risk level (typical agent release events) to be “acceptable with controls” or “acceptable.”

Notes: Stakeholders are often regarded as a critically important group in such issues as the siting of nuclear facilities. In this article, stakeholders were identified on the basis of self-reported activities with regard to a nuclear waste siting issue under debate in four communities. Data were obtained in an extensive mailed survey from a total of 2,548 respondents, approximately an equal number from each community. The overall response rate was 43.9%. Some of the results and telephone interviews with a sample of the nonrespondents indicated that the data are reasonably representative of the respective populations. Stakeholder activities were measured by 20 questions and combined with an index of stakeholder activity level, dichotomized at the 90th percentile. Stakeholders were found to have a higher level of education than others, but otherwise they did not differ in demographics. They did not tend to see risks in general as high, but were quite interested and involved in the nuclear waste siting issue. The stakeholder activity level correlated with risk perception and attitudes in the waste siting issue, but with different signs for those who were for and those who were opposed: stakeholders of both types had more extreme views than others, but in different directions. In addition, stakeholder opponents were much more likely to strongly espouse extreme statements regarding the project than were supporters who also were stakeholders. Implications for risk management and communication are discussed.

Notes: Public policies to mitigate the impacts of extreme events such as hurricanes or terrorist attacks will differ depending on whether they focus on reducing risk or reducing vulnerability. Here we present and defend six assertions aimed at exploring the benefits of vulnerability-based policies. (1) Risk-based approaches to covering the costs of extreme events do not depend for their success on reduction of vulnerability. (2) Risk-based approaches to preparing for extreme events are focused on acquiring accurate probabilistic information about the events themselves. (3) Understanding and reducing vulnerability does not demand accurate predictions of the incidence of extreme events. (4) Extreme events are created by context. (5) It is politically difficult to justify vulnerability reduction on economic grounds. (6) Vulnerability reduction is a human rights issue; risk reduction is not.

Notes: This article provides a systematic framework for the analysis and improvement of near-miss programs in the chemical process industries. Near-miss programs improve corporate environmental, health, and safety (EHS) performance through the identification and management of near misses. Based on more than 100 interviews at 20 chemical and pharmaceutical facilities, a seven-stage framework has been developed and is presented herein. The framework enables sites to analyze their own near-miss programs, identify weak management links, and implement systemwide improvements.

Notes: Formaldehyde induced squamous-cell carcinomas in the nasal passages of F344 rats in two inhalation bioassays at exposure levels of 6 ppm and above. Increases in rates of cell proliferation were measured by T. M. Monticello and colleagues at exposure levels of 0.7 ppm and above in the same tissues from which tumors arose. A risk assessment for formaldehyde was conducted at the CIIT Centers for Health Research, in collaboration with investigators from Toxicological Excellence in Risk Assessment (TERA) and the U.S. Environmental Protection Agency (U.S. EPA) in 1999. Two methods for dose-response assessment were used: a full biologically based modeling approach and a statistically oriented analysis by benchmark dose (BMD) method. This article presents the later approach, the purpose of which is to combine BMD and pharmacokinetic modeling to estimate human cancer risks from formaldehyde exposure. BMD analysis was used to identify points of departure (exposure levels) for low-dose extrapolation in rats for both tumor and the cell proliferation endpoints. The benchmark concentrations for induced cell proliferation were lower than for tumors. These concentrations were extrapolated to humans using two mechanistic models. One model used computational fluid dynamics (CFD) alone to determine rates of delivery of inhaled formaldehyde to the nasal lining. The second model combined the CFD method with a pharmacokinetic model to predict tissue dose with formaldehyde-induced DNA-protein cross-links (DPX) as a dose metric. Both extrapolation methods gave similar results, and the predicted cancer risk in humans at low exposure levels was found to be similar to that from a risk assessment conducted by the U.S. EPA in 1991. Use of the mechanistically based extrapolation models lends greater certainty to these risk estimates than previous approaches and also identifies the uncertainty in the measured dose-response relationship for cell proliferation at low exposure levels, the dose-response relationship for DPX in monkeys, and the choice between linear and nonlinear methods of extrapolation as key remaining sources of uncertainty.

Notes: With the growing number and diversity of hazard and risk assessment algorithms, models, databases, and frameworks for chemicals and their applications, risk assessors and managers are challenged to select the appropriate tool for a given need or decision. Some decisions require relatively simple tools to evaluate chemical hazards (e.g., toxicity), such as labeling for safe occupational handling and transport of chemicals. Others require assessment tools that provide relative comparisons among chemical properties, such as selecting the optimum chemical for a particular use among a group of candidates. Still other needs warrant full risk characterization, coupling both hazard and exposure considerations. Examples of these include new chemical evaluations for commercialization, evaluations of existing chemicals for novel uses, and assessments of the adequacy of risk management provisions. Even well-validated tools can be inappropriately applied, with consequences as severe as misguided chemical management, compromised credibility of the tool and its developers and users, and squandered resources. This article describes seven discrete categories of tools based on their information content, function, and the type of outputs produced. It proposes a systematic framework to assist users in selecting hazard and risk assessment tools for given applications. This analysis illustrates the importance of careful selection of assessment tools to achieve responsible chemical assessment communication and sound risk management.

Notes: Climate change may well lead to an increased risk of river floods in the Netherlands. However, the impacts of changes in water management on river floods are larger, either enhancing or reducing flood risks. Therefore, the abilities of water-management authorities to learn that climate and river flows are changing, and to recognize and act upon the implications, are of crucial importance. At the same time, water-management authorities respond to other trends, such as the democratization of decision making, which alter their ability to react to climate change. These complex interactions are illustrated with changes in river flood risk management for the Rhine and the Meuse in the Netherlands over the last 50 years. A scenario study is used to seek insight into the question of whether current water-management institutions and their likely successors are capable of dealing with plausible future flood risks. The scenarios show that new and major infrastructure is needed to keep flood risks at their current level. Such a structural solution to future flood risks is feasible, but requires considerable political will and institutional reform, both for planning and implementation. It is unlikely that reform will be fast enough or the will strong enough.

Notes: Under current conditions of accelerated socioenvironmental change in the Mediterranean forested landscapes, fire is one of the most critical and difficult risks to tackle within the region. This article summarizes the lessons learned from a project based on the participatory integration of qualitative local stakeholders' knowledge with expert GIS fire simulations carried out in the County of El Bages, Catalonia, Spain. First, in this article, a theoretical model—the forest fire circle—is presented in order to explain the reasons for the rise in the damage and frequency of forest fires in this Mediterranean area. Second, it describes the methodology developed and the stages followed during the project. Results show that: (1) the advocacy of old forest reactive management paradigm assumptions and practices based on uncontrolled forest succession can put vast wooded areas of the Mediterranean basin at critical risk; and (2) forest fire management approaches that ignore the crucial role of long-term prevention and local capacity building strategies have failed. In the final section, the content and the specific dimensions of the old reactive paradigm that has characterized forest fire risk management in Catalonia are discussed and contrasted with the possibly emerging preventative paradigm.

Notes: Risk disputes are often characterized by tensions between technical and cultural understandings of risk and by communication practices that reflect those differing perspectives. This study considers how participants in risk debates draw upon and combine aspects of technical and cultural rationality as broad orientations to risk in expressing their views and formulating persuasive appeals during risk debates. Rhetorical theorist Kenneth Burke's (1984) concept of frames of acceptance is used to analyze a case study involving competing priorities for radium stored at the Fernald site, a former Department of Energy nuclear weapons facility. A rhetorical analysis is conducted using the transcript from a 1995 public meeting during which local residents and a nuclear medicine expert discussed priorities of Fernald site cleanup versus providing radium stored on site for promising cancer research. Two tensions are identified that fostered disagreement among discussants: the first a tension between a local or global context for the controversy and the second a tension between competing definitions of public participation for this issue. This study analyzes the rhetorical strategies by which participants in the Fernald radium debate articulated these tensions and argues that technical and cultural rationality (Plough & Krimsky, 1987) acted as sources of rhetorical invention influencing participants' individual frames of acceptance and the ways they defined and interpreted the situation and crafted persuasive appeals.

Notes: This article explores the possible social costs of introducing an overly precautionary regulatory regime for chemicals. It begins by examining research by the UK Medical Research Council Institute for Environment and Health (MRC-IEH), which suggests that the resource implications of the proposals contained in the European Commission White Paper “Strategy for a Future Chemicals Policy”(1) are unrealistic and even unrealizable. The article then focuses on contemporary debates pertaining to endocrine disrupting chemicals (EDCs) and goes on to question whether a “right to know” is always necessarily a good thing, or whether in certain instances it can lead to a society that feels more sorry than safe.(2) Finally, problems relating to the representation and inclusion of public values in decision-making processes are raised prior to concluding with a call for an ambitious orientation toward social change rather than a self-limiting obsession with safety.

Notes: Recent research suggests that public attitudes toward emerging technologies are mainly driven by trust in the institutions promoting and regulating these technologies. Alternative views maintain that trust should be seen as a consequence rather than a cause of such attitudes. To test its actual role, direct as well as mediating effects of trust were tested in an attitude change experiment involving 1,405 consumers from Denmark, Germany, Italy, and the United Kingdom. After prior attitudes to genetic modification in food production had been assessed, participants received different information materials (either product-specific information or balanced/general information about genetic modification in food production) and were asked to evaluate different types of genetically modified foods (either beer or yoghurt). The information materials were attributed to different information sources (either an industry association, a consumer organization, or a government source). After completion, perceived risk and perceived benefit were assessed, and participants indicated their trust in the information sources to which the materials had been attributed. Direct and trust-mediated attitude change effects were estimated in a multi-sample structural equation model. The results showed that information provision had little effect on people's attitudes toward genetically modified foods, and that perceptions of information source characteristics contributed very little to attitude change. Furthermore, the type of information strategy adopted had almost no impact on postexperimental attitudes. The extent to which people trusted the information sources appeared to be driven by people's attitudes to genetically modified foods, rather than trust influencing the way that people reacted to the information. Trust was not driving risk perception—rather, attitudes were informing perceptions of the motivation of the source providing the information.

Notes: In recent years, there has been increased interest in the development and use of quantitative structure-activity/property relationship (QSAR/QSPR) models. For the most part, this is due to the fact that experimental data is sparse and obtaining such data is costly, while theoretical structural descriptors can be obtained quickly and inexpensively. In this study, three linear regression methods, viz. principal component regression (PCR), partial least squares (PLS), and ridge regression (RR), were used to develop QSPR models for the estimation of human blood:air partition coefficient (logPblood:air) for a group of 31 diverse low-molecular weight volatile chemicals from their computed molecular descriptors. In general, RR was found to be superior to PCR or PLS. Comparisons were made between models developed using parameters based solely on molecular structure and linear regression (LR) models developed using experimental properties, including saline:air partition coefficient (logPsaline:air) and olive oil:air partition coefficient (logPolive  oil:air), as independent variables, indicating that the structure-property correlations are comparable to the property-property correlations. The best models, however, were those that used rat logPblood:air as the independent variable. Haloalkane subgroups were modeled separately for comparative purposes and, although models based on the congeneric compounds were superior, the models developed on the complete set of diverse compounds were of acceptable quality. The structural descriptors were placed into one of three classes based on level of complexity: topostructural (TS), topochemical (TC), or three-dimensional/geometrical (3D). Modeling was performed using the structural descriptor classes both in a hierarchical fashion and separately. The results indicate that highest quality structure-based models, in terms of descriptor classes, were those derived using TC descriptors.

Notes: A common problem with medical surveillance programs using biomarkers is determining the optimal frequency of testing to minimize adverse health effects and cost. In the case of beryllium-exposed workers, frequency of testing for beryllium sensitization may be especially important. Recent studies indicate a lack of dose response for beryllium sensitization, but do support a dose response for the development of chronic beryllium disease (CBD). Though unproven, this implies that early identification of sensitization and immediate removal from exposure may reduce development of CBD. A model is proposed to project the optimal frequency of sensitization testing using the current beryllium lymphocyte proliferation test (BeLPT) to minimize disease-related costs, assuming that a positive BeLPT will precede CBD. Conversion rates for cumulative exposure to disease development were adapted from the literature and used with testing costs and cost of disease estimates in the model. The model was run assuming several test frequency regimes. Results support the use of periodic testing in line with the annual schedule proposed in the Final Chronic Beryllium Disease Prevention Program Rule (1999) following initial testing within three months of first beryllium exposure. The financial and health benefits of reducing the time from exposure to detection of early disease was also explored with the model and demonstrated as a highly desirable characteristic for an alternative test or improved BeLPT. Limitations of the approach are discussed as well as options for adapting this biomarker optimization methodology to consider biomarkers of other exposure-associated diseases.

Notes: In this work we characterize risk perception in Chile, based on the psychometric paradigm, exploring the difference between perceived social and personal risk. For this purpose, we conducted a survey including 54 hazards, 16 risk attributes, and 3 risk constructs. The survey, divided into four parts, was administered to 508 residents of Santiago, Chile. Using factor analysis, three main factors, which accounted for 80% of the sample's variance, were identified: factor 1, commonly called “Dread Risk” in the literature, explained 37% of variance; factor 2, “Unknown Risk,” explained 28%; and factor 3, which we called “Personal Effect,” explained 15% of the variance. On average, individuals perceived themselves as less exposed to risk and with more control and knowledge about them than the general population. OLS regression models were used to test the association of perceived risk with the three main factors. For social risk, factor 1 had the greatest explanatory power, while factor 2 had a negative sign. For personal risk, only factors 2 and 3 were significant, with factor 3 having the greatest explanatory power. Risk denial (defined as the difference between perceived personal and social risk) was associated with factors 1 and 2 only, with factor 2 having a negative sign. The difference between desired and actual regulation levels proved positive for all hazards, thus indicating that Chileans are dissatisfied with the current regulation level for all the hazards analyzed. The comparison of data at the aggregate and at the individual subject's level suggests that while the aggregate analysis overestimates the magnitude of the correlations it still reflects the tendency of the individual responses.

Notes: The 1991 eruption of Mount Pinatubo in the Philippines is considered one of the most violent and destructive volcanic activities in the 20th century. Lahar is the Indonesian term for volcanic ash, and lahar flows resulting from the massive amount of volcanic materials deposited on the mountain's slope posed continued post-eruption threats to the surrounding areas, destroying lives, homes, agricultural products, and infrastructures. Risks of lahar flows were identified immediately after the eruption, with scientific data provided by the Philippine Institute of Volcanology, the U.S. Geological Survey, and other research institutions. However, competing political, economic, and social agendas subordinated the importance of scientific information to policy making. Using systemic risk analysis and management, this article addresses the issues of multiple objectives and the effective integration of scientific techniques into the decision-making process. It provides a modeling framework for identifying, prioritizing, and evaluating policies for managing risk. The major considerations are: (1) applying a holistic approach to risk analysis through hierarchical holographic modeling, (2) applying statistical methods to gain insight into the problem of uncertainty in risk assessment, (3) using multiobjective trade-off analysis to address the issue of multiple decisionmakers and stakeholders in the decision-making process, (4) using the conditional expected value of extreme events to complement and supplement the expected value in quantifying risk, and (5) assessing the impacts of multistage decisions. Numerical examples based on ex post data are formulated to illustrate applications to various problems. The resulting framework from this study can serve as a general baseline model for assessing and managing risks of natural disasters, which the Philippines' lead agency—the National Disaster Coordinating Council (NDCC)—and other related organizations can use for their decision-making processes.

Notes: This article reports on the data collected on one of the most ambitious government-sponsored environmental data acquisition projects of all time, the Risk Management Plan (RMP) data collected under section 112(r) of the Clean Air Act Amendments of 1990. This RMP Rule 112(r) was triggered by the Bhopal accident in 1984 and led to the requirement that each qualifying facility develop and file with the U.S. Environmental Protection Agency a Risk Management Plan (RMP) as well as accident history data for the five-year period preceding the filing of the RMP. These data were collected in 1999–2001 on more than 15,000 facilities in the United States that store or use listed toxic or flammable chemicals believed to be a hazard to the environment or to human health of facility employees or off-site residents of host communities. The resulting database, RMP*Info, has become a key resource for regulators and researchers concerned with the frequency and severity of accidents, and the underlying facility-specific factors that are statistically associated with accident and injury rates. This article analyzes which facilities actually filed under the Rule and presents results on accident frequencies and severities available from the RMP*Info database. This article also presents summaries of related results from RMP*Info on Offsite Consequence Analysis (OCA), an analytical estimate of the potential consequences of hypothetical worst-case and alternative accidental releases on the public and environment around the facility. The OCA data have become a key input in the evaluation of site security assessment and mitigation policies for both government planners as well as facility managers and their insurers. Following the survey of the RMP*Info data, we discuss the rich set of policy decisions that may be informed by research based on these data.

Notes: Geostatistics offers two fundamental contributions to environmental contaminant exposure assessment: (1) a group of methods to quantitatively describe the spatial distribution of a pollutant and (2) the ability to improve estimates of the exposure point concentration by exploiting the geospatial information present in the data. The second contribution is particularly valuable when exposure estimates must be derived from small data sets, which is often the case in environmental risk assessment. This article addresses two topics related to the use of geostatistics in human and ecological risk assessments performed at hazardous waste sites: (1) the importance of assessing model assumptions when using geostatistics and (2) the use of geostatistics to improve estimates of the exposure point concentration (EPC) in the limited data scenario. The latter topic is approached here by comparing design-based estimators that are familiar to environmental risk assessors (e.g., Land's method) with geostatistics, a model-based estimator. In this report, we summarize the basics of spatial weighting of sample data, kriging, and geostatistical simulation. We then explore the two topics identified above in a case study, using soil lead concentration data from a Superfund site (a skeet and trap range). We also describe several areas where research is needed to advance the use of geostatistics in environmental risk assessment.

Notes: Pollutant emissions or ambient levels are often justified by reference to a higher benchmark, such as a public health standard or permit limit. However, does this risk comparison persuade the public audiences to whom it is frequently directed that such pollution levels are “acceptable”? A substantial proportion of people living within one mile of New Jersey's industrial facilities, perhaps as much as half, is indeed reassured by a comparison to such benchmarks. Positive attitudes toward discharge limits were linked to speaking English at home; positive attitudes toward drinking water standards were associated with seeing local benefits of industry as outweighing its risks, not speaking English, and relative youth (49 years old or less). Three scenarios involving drinking water contamination varied pre- and post-treatment levels of the pollutant, though all post-treatment levels were below the standard. In all cases great concern was expressed, with no significant differences across scenarios; net benefits, being white, and non-English speaking were linked to lower concern. Relative trust seems a better explanation of different attitudes toward benchmark comparisons than varying levels of knowledge, but both hypotheses have drawbacks that merit further testing. These results imply that people with negative views of industry or government, the ones officials might most wish to reassure, will tend to doubt that regulatory benchmarks offer a valid risk comparison.

Notes: Two approaches to measuring perceptions of synergistic risk were compared, one using the traditional Likert scale, the other using an anchored, relative scale. Perception of synergistic risk was defined as rating the combined hazard as more risky than each of its constituent single hazards. In a within-subjects design, a convenience sample from the community (N= 604) rated three hazard combinations and their constituents: Driving while Intoxicated (familiar, high synergy), Radon and Smoking (unfamiliar, high synergy), and Smoking and Driving (familiar, low synergy), on both scales. The relative scale was expected to be a more sensitive measure of synergy than the Likert scale. The effects of item order (single hazards rated first versus combined hazards rated first) were examined between subjects. Driving while Intoxicated was perceived by the large majority of participants as a synergistic risk on both scales, but neither of the other two combined hazards were rated synergistically on either scale. The relative scale demonstrated a slight advantage over the Likert scale, and presenting the single hazards first for the relative scale produced more synergistic ratings. It is recommended that anchored, relative scales be used to measure synergy and that single hazards be presented prior to the combined hazards when using relative scales.

Notes: Policy makers, vehicle manufacturers, and consumers have shown growing concern about the relative safety of sport utility vehicles (SUVs), vans, pickups, and cars. Empirical analysis of real-world crashes is complicated by the possibility that apparent relationships between vehicle type and safety may be confounded by other factors, such as driver behavior and crash circumstances. This study compares different vehicle types with respect to their crashworthiness (self-protection) and aggressivity (risk to others) in crashes between two passenger vehicles. The U.S. Crashworthiness Data System is used to analyze detailed information on 6,481 drivers involved in crashes during 1993–1999. Logistic regression analysis is used to model the risk of serious injury or death to a driver, conditional on a crash occurring. Covariates include the body type of each vehicle in the crash; the driver's age, gender, and restraint use; and the configuration of the crash. A unique feature of this study is the use of “delta-v” to represent the joint effects of vehicle mass and crash severity. While estimated effects are somewhat sensitive to the injury severity level used as the outcome variable, SUVs, vans, and pickups appear to be more aggressive and may be more crashworthy than cars. Effects of pickups are most pronounced. Drivers in pickups face less risk of serious injury than car drivers (odds ratio [OR], 0.35; 95% confidence interval [CI], 0.20–0.60), and drivers who collide with pickups experience more than twice the risk than those who collide with a car (OR, 2.18; 95% CI, 1.03–4.62). While vehicle mass and crash severity contribute to the apparent crashworthiness and aggressivity of passenger vehicles, other vehicle characteristics associated with body type (e.g., the stiffness and height of the underlying structure of the vehicle) also influence safety risks.

Notes: The terrorist acts of September 11, 2001 were a wake-up call for changing our traditional response to risks of terrorism. Given that government and worldwide think-tank organizations maintain that risks of terrorism will continue for the indefinite future, the following questions deserve strategic answers. How long can we respond to terrorism with tactical measures only, sustain current curtailments of some of our freedoms, travel, and quality of life, and absorb losses in human life and properties? Should not underlying strategic motivation lead to the tactical measures? Why do so many groups and individuals in some developing countries hate us? Is it because they fear that the ideas we export through television, movies, literature, and music have a corrupting influence on their cultures? Is it because of past operations that we conducted in such countries as Iran, Nicaragua, El Salvador, and Granada? Can the genesis of the risks of terrorism to the homeland be traced to the unfavorable socioeconomic conditions in less-privileged and developing countries, where civil and religious freedoms are close to nonexistent, and sanitary conditions, health and education, and critical infrastructures of essential utilities are almost at the same level that existed in the United States almost a century ago? If we could make progress at improving the quality of life of the billions of people in the developing countries and become more sensitive to their needs, cultures, and heritage, would their hatred subside? What other measures can we take to reduce their hatred, without compromising our basic cultural and democratic principles or their cultural and social heritage?

Notes: Mercury contamination of aquatic ecosystems is a global environmental concern. Bioaccumulation of mercury in fish exposes consumers to risk. We interviewed ice anglers on Monona Bay, Wisconsin during the 2001–2002 ice fishing season to determine risk associated with fish consumption and methyl mercury (MeHg) intake. The majority of anglers (95%) were not at risk of mercury toxicity because they ate less fish than would be required to create health problems. The remaining 5% of ice anglers barely exceeded the mercury toxicity threshold, with the exception of one angler who exceeded the threshold by 0.926 ppm. Anglers encountered were all male and predominantly Caucasian. Fish consumption by ice anglers was independent of awareness of consumption advisories, education, income, and age. This suggests that future awareness efforts should (1) identify groups of anglers most at risk and (2) create policies to effectively reach these audiences.

Notes: Whether the floods experienced during the last decade in Germany and in other European countries are triggered or worsened by human activities has been the subject of a great deal of debate. Possible anthropogenic activities leading to increased flood risk include river regulation measures, intensified land use and forestry, and emissions of greenhouse gases causing a change in the global climate. This article discusses the latter by reviewing the existing knowledge on the subject. First, the relevance, capabilities, and limitations of climate models for the simulation and analysis of flood risk under aspects of the anthropogenic climate change are described. Special consideration is given here to differences between the “typical” spatial scale of climate models and hydrological flood models. Second, observations of trends in climate variables relevant for river flooding issues are summarized. Special emphasis is put on the Rhine and other German catchment areas. Third, the possibilities of modeling the different parts of the “cascade of flood risk” are summarized, introducing the special features of meteorological, hydrological, and river hydraulic models.

Notes: With escalating costs of flood mitigation and relief, a challenge for the Hungarian government is to develop a flood mitigation and insurance/relief system that is viewed as efficient and fair by the many stakeholders involved. To aid policymakers in this task, this article reports on a recent study to elicit stakeholder views on flood risk management in the Upper Tisza Basin, including views on appropriate means of reducing losses and for transferring the residual losses from the direct victims to taxpayers or an insurance pool. This study is part of a project to develop an integrated approach to flood risk management coordinated by the International Institute of Applied Systems Analysis (IIASA) in collaboration with Swedish and Hungarian researchers. The discussion begins by describing the background of flood risk management problems in the Upper Tisza Basin. The results of interviews carried out with selected key stakeholders and the results of a public survey eliciting views on flood risk management are reported. The final section draws conclusions on incorporating stakeholder views into a flood risk management model, which will be used to illustrate policy paths at an upcoming stakeholder workshop. The conclusions are also of direct interest to Hungarian policymakers.

Notes: This article examines the potential of pre- and post-disaster instruments for funding disaster response and recovery and for creating incentives for flood loss mitigation in countries with emerging or transition economies. As a concrete case, we discuss the disaster recovery arrangements following the 1997 flood disaster in Poland. We examine the advantages and limitations of hedging instruments, which are instruments for transferring the risk to investors either through insurance or capital market-based securities. We compare these mechanisms with financing instruments, whereby the government sets aside funds prior to a disaster or taps its own funding sources after the event occurs. We show how hedging instruments can be designed to create incentives for the mitigation of damage to public infrastructure using the flood proofing of a water-treatment plant on the hypothetical Topping River as an illustrative example. We conclude that hedging instruments can be an attractive alternative to financing instruments that have been traditionally used in the poorer, emerging-economy countries to fund disaster recovery. Since very poor countries are likely to have difficulty paying the price of protection prior to a disaster, we suggest that international lending institutions consider innovations for subsidizing these payments.

Notes: The role of risk communication and public participation in environmental and public policy decision making has significantly increased over the last 15 years and remains an important social policy issue. In spite of this emphasis, government officials and participants in the process continue to struggle with what makes for “good” public participation. This study used two frameworks—one theoretical and one participant-based—to evaluate two U.S. Army Restoration Advisory Boards (RABs). The theoretical framework explores the extent to which the RABs facilitate Habermas's idealized conditions of speech as related to fairness. Not surprisingly, we found that the two RABs do not consistently foster the idealized aspects of fairness suggested by Habermas. The participant-based criteria were elicited through interviews with participants from the various stakeholder groups represented on the RAB, direct observation of RAB meetings, and a review of RAB-related documents. We found that participants' value outcomes (the results of participatory processes) and not just the process itself, which is the focus of the theoretical framework. We also found that participants in the various stakeholder groups had different perceptions of the goals of the participatory process, which were closely related to their notions of success. Our results illustrate both the complexity and importance of using multiple frameworks for evaluating participatory efforts and the need for more systematic evaluation.

Notes: The causal structure of the determinants of trust in industry, government, and citizen's groups in Japan was investigated on the basis of Peters et al. (1997). A preliminary survey of the adequacy of the hypotheses proposed by Peters et al. in Japan was made. A set of hypothesized determinants of trust in Japan was proposed based on results of the preliminary survey. Questionnaires concerning perceptions of trust in the organizations and the proposed determinants were sent by mail to residents in the area where environmental risk problems had emerged. The data were analyzed by covariance structure analysis to construct models of trust in industry, government, and citizen's groups. As a result, “openness and honesty,”“concern and care,”“competence,”“people's concern with risks,” and “consensual values” were found to be factors directly determining trust. Suggested in particular is that “openness” of an organization is not attained merely by information disclosure, but also by bi-directional communication with the people. Moreover, these models include “consensual values,” which do not appear in the model proposed by Peters et al.

Notes: The European Commission has proposed a radical new policy for the regulation of chemicals in the EU in the form of a White Paper. The current system has separate regulatory provisions for “new” chemicals (introduced to the market since September 18, 1981) and “existing” chemicals (on the market before September 18, 1981). The proposed future policy will have a single unified regulatory system for all chemicals, which should result in better regulation of chemicals in the EU single market. It will be better because risk assessments will be targeted at the chemicals of greatest concern. Furthermore, the system will be streamlined, making regulatory decisions faster, and thus reducing the so-called burden of the past (the large number of chemicals that have never been assessed for their risks to human health or the environment). The new system incorporates the precautionary principle, which will be applied where there is an early indication of unacceptable risk or where there is undue delay in the regulatory process. Moreover, the new strategy is intended to promote greater transparency for all stakeholders.

Notes: Using a model of risk information seeking and processing developed by Griffin, Dunwoody, and Neuwirth (1999), this study looks at predictors of the processing strategies that people apply to health risk information. Specifically, this article focuses on one relationship within the model—the relationship between perceived amount of information needed to deal with a risk and heuristic-systematic processing. Perceived amount of information needed refers to the gap between one's understanding of a risk and the level of understanding that one needs in order to make a decision about that risk. Building on the work of Chaiken (cf. 1980), the Griffin et al. model predicts—and finds—that the larger the gap, the more likely one will process information systematically. The study employs a novel measure of information processing in a survey setting by sending actual information to participants and then asking them how they attended to it; the researchers evaluate this strategy. Finally, the researchers discuss how these findings might help agencies and practitioners create more effective risk messages.

Notes: After years of good service, EU legislation on chemicals is currently subject to a major review. This process, initiated by the Council of Ministers at Chester in April 1998, will soon lead to new legislative proposals. In the meantime, a review of the Commission's White Paper on “Strategy for a Future Chemicals Policy,” published in February 2001, clearly shows that the regulatory landscape in this area will be significantly reshaped and that a new burden will be imposed on industry to demonstrate that the production and use of chemicals indeed conform to high standards of protection of human health and the environment. In the view of industry, on both sides of the Atlantic, while the objectives of the proposed reform can be supported, the measures proposed in the White Paper to implement these objectives are not properly balanced and will lead to substantial societal and economic drawbacks, unless significant adjustments are made. The purpose of this article is to present the pitfalls and difficulties of the reform as they are perceived by the EU Committee of the American Chamber of Commerce in Brussels, an organization that regroups about 150 European companies of American parentage, belonging to a broad range of European business sectors, including producers and users of chemicals. In view of the transatlantic and cross-business character of its membership, the EU Committee offers a different perspective on the debate.

Notes: For the vast majority of chemicals that have cancer potency estimates on IRIS, the underlying database is deficient with respect to early-life exposures. This data gap has prevented derivation of cancer potency factors that are relevant to this time period, and so assessments may not fully address children's risks. This article provides a review of juvenile animal bioassay data in comparison to adult animal data for a broad array of carcinogens. This comparison indicates that short-term exposures in early life are likely to yield a greater tumor response than short-term exposures in adults, but similar tumor response when compared to long-term exposures in adults. This evidence is brought into a risk assessment context by proposing an approach that: (1) does not prorate children's exposures over the entire life span or mix them with exposures that occur at other ages; (2) applies the cancer slope factor from adult animal or human epidemiology studies to the children's exposure dose to calculate the cancer risk associated with the early-life period; and (3) adds the cancer risk for young children to that for older children/adults to yield a total lifetime cancer risk. The proposed approach allows for the unique exposure and pharmacokinetic factors associated with young children to be fully weighted in the cancer risk assessment. It is very similar to the approach currently used by U.S. EPA for vinyl chloride. The current analysis finds that the database of early life and adult cancer bioassays supports extension of this approach from vinyl chloride to other carcinogens of diverse mode of action. This approach should be enhanced by early-life data specific to the particular carcinogen under analysis whenever possible.

Notes: In recent years, much attention has focused on how to incorporate environmental equity considerations into government permitting programs for environmentally regulated facilities. On February 4, 2002, the New Jersey Department of Environmental Protection (NJDEP) became the first state environmental agency to propose a broad legally binding rule intended to guard against environmental inequity in its permitting decisions. The proposed rule centered on an innovative computerized environmental equity (EE) screening model that used “Population Emissions Ratios” to identify small geographic areas in which environmental equity concerns might exist and to simulate the effect on statewide environmental equity of increasing environmental risks in small geographic areas. The NJDEP's model examined an extensive array of ethnic groups, included a variety of environmental risks, evaluated most of those risks in terms of human health, and used an innovative simulation process designed to identify permitting decisions that would worsen statewide environmental inequity. The results of the NJDEP's efforts, however, pose substantial concerns. For example, some key provisions of the NJDEP's model were inadequately explained and some were illogical and would bias its results. The model might be susceptible to generating implausible results due to small, meaningless, and/or essentially random fluctuations in its data inputs. The model used relatively large geographic areas as the units of analysis and interpolated results between them, rather than using smaller geographic areas and avoiding interpolation errors. Finally, the environmental risks evaluated by the model were both arguably over- and underinclusive. Thus, the NJDEP's efforts, although noteworthy, raised more issues than they settled.

Notes: A long-running effort in environmental communication is daily publication of a report on local air pollution in many American newspapers based on the Pollutant Standards Index (PSI). A 1998 proposal by the U.S. Environmental Protection Agency (U.S. EPA) to change the PSI prompted a survey experiment with 1,100 adults in Philadelphia, evaluating the proposed change's ability to better inform the populace. The effects of exposure to the old and new versions of the PSI, as well as health cautions and information about groups sensitive to air pollution, were compared with evaluation criteria suggested by Weinstein and Sandman (1993). Sample respondents had strong baseline concerns about air pollution. Descriptors of air quality (e.g., “good; ”“unhealthy”) were difficult to discriminate, particularly in the New format. Concern rose as hypothetical air pollution levels rose, but the New format (as well as PSI versions without health cautions or sensitive-group information) evoked a sharp discontinuity in concern between below- and above-standard pollution levels. Both Old and New formats reduced concern relative to no provision of PSI information at all, but the New format reduced concern significantly more than the Old version. No PSI format did particularly well at increasing knowledge of air pollution or decreasing intentions to be active outdoors during high pollution, contrary to the agency's aim. Although U.S. EPA has since adopted the new proposal as a national “Air Quality Index” requirement, the experiment's results illuminate the strengths and limitations of the new PSI as a means of informing citizens and motivating them to protect themselves.

Notes: Screening and testing for potential thyroid toxicants using endpoints of thyroid function, including circulating levels of thyroid hormones and thyrotropin, will not capture toxicants that directly interfere with thyroid hormone action at the receptor. The goals of the present review are to provide a critique of the literature focused on thyroid hormone and brain development as it relates to testing and evaluating thyroid toxicants, and to propose possible solutions to this perceived dilemma.

Notes: The abilities of cells of a particular type of bacteria to leave lag phase and begin the process of dividing or surviving heat treatment can depend on the serotypes or strains of the bacteria. This article reports an investigation of serotype-specific differences in growth and heat resistance kinetics of clinical and food isolates of Salmonella. Growth kinetics at 19°C and 37°C were examined in brain heart infusion broth and heat resistance kinetics for 60°C were examined in beef gravy using a submerged coil heating apparatus. Estimates of the parameters of the growth curves suggests a small between-serotype variance of the growth kinetics. However, for inactivation, the results suggest a significant between-serotype effect on the asymptotic D-values, with an estimated between-serotype CV of about 20%. In microbial risk assessment, predictive microbiology is used to estimate growth and inactivation of pathogens. Often the data used for estimating the growth or inactivation kinetics are based on measurements on a cocktail—a mixture of approximately equal proportions of several serotypes or strains of the pathogen being studied. The expected growth or inactivation rates derived from data using cocktails are biased, reflecting the characteristics of the fastest growing or most heat resistant serotype of the cocktail. In this article, an adjustment to decrease this possible bias in a risk assessment is offered. The article also presents discussion of the effect on estimating growth when stochastic assumptions are incorporated in the model. In particular, equations describing the variation of relative growth are derived, accounting for the stochastic variations of the division of cells. For small numbers of cells, the expected value of the relative growth is not an appropriate “representative” value for actual relative growths that might occur.

Notes: Staphylococcus aureus is a gram-positive, enterotoxin-producing coccus. It is a hardy organism and known to survive over a wide range of water activities, pH values, and temperatures. The objective of this study was to model the survival or gradual inactivation of S. aureus ATCC 13565 in intermediate moisture foods (IMFs). Various initial concentrations (∼101, 102, 103, and 104 CFU/g) were used to inoculate three different IMFs (beefsteak, bread, and chicken pockets). Viable counts were determined up to 60 days using tryptic soy agar. Inoculum size did not influence the survival or gradual inactivation of S. aureus in these foods. The rate of change (increase or decrease) in log CFU/day was calculated for every consecutive pair of data points and by linear regression for each inactivation curve. Both consecutive pair and linear regression rates of change were fit to logistic distributions (with parameters α and β) for each food. Based on the distribution parameters, survival or gradual inactivation of S. aureus was predicted by computer simulation. The simulations indicated an overall decline in S. aureus population over time, although a small fraction of samples in the consecutive pair simulation showed a slight population increase even after 60 days, consistent with the observed data. Simulation results were compared to predictions from other computer models. The models of Stewart et al.(1) were fail-safe, predicting the possibility of significant growth only after 〉3,000 days. The USDA pathogen modeling program predictions were found to be fail-dangerous, predicting declines at least four times faster than observed.

Notes: Whereas the verdict is undecided about the effects of global warming on Europe's flood risks, it is clear that Europeans are becoming more exposed and vulnerable to floods. Losses are increasing dramatically, mainly because of population and capital moving into harm's way and also because of human-driven transformations of hydrological systems, including river basins and floodplains.

Notes: This article examines two possible strategies for financing post-disaster infrastructure rehabilitation in developing and transition countries: relying on ex ante financing instruments (including insurance, catastrophe bonds, and other risk-transfer instruments) and ex post borrowing or credit. Insurance and other ex ante instruments will increase a country's stability, especially if the government authorities have a difficult time borrowing or otherwise raising funds after a major disaster; however, these instruments have an opportunity cost and can reduce the country's economic growth potential. The cost-benefit tradeoff is therefore one between economic growth through infrastructure investment and added solvency and stability for the economy. This article develops a model to illustrate this tradeoff. The model, which views the infrastructure of a developing or transition country as a nondiversifiable portfolio that generates returns, can provide a basis for evaluating alternative financing options depending on the country's objectives in terms of growth, solvency, and stability.

Notes: The occurrence of arsenic in drinking water is an issue of considerable interest. In the case of Bangladesh, arsenic concentrations have been closely monitored since the early 1990s through an extensive sampling network. The focus of the present work is methodological. In particular, we propose the application of a holistochastic framework of human exposure to study lifetime population damage due to arsenic exposure across Bangladesh. The Bayesian Maximum Entropy theory is an important component of this framework, which possesses solid theoretical foundations and offers powerful tools to assimilate a variety of knowledge bases (physical, epidemiologic, toxicokinetic, demographic, etc.) and uncertainty sources (soft data, measurement errors, etc.). The holistochastic exposure approach leads to physically meaningful and informative spatial maps of arsenic distribution in Bangladesh drinking water. Global indicators of the adverse health effects on the population are generated, and valuable insight is gained by blending information from different scientific disciplines. The numerical results indicate an increased lifetime bladder cancer probability for the Bangladesh population due to arsenic. The health effect estimates obtained and the associated uncertainty assessments are valuable tools for a broad spectrum of end-users.

Notes: It has been suggested that public participation during decision making about risks can lead to more widely accepted risk policies. This article discusses an experiment to determine if this is true when people are made aware of the fact that a participatory decision-making process has taken place only through information disclosed during a subsequent risk communication effort. The results from this experiment showed that, after receiving information during risk communication that cast risk policies about space exploration as the product of a participatory decision process, participants in the study felt more supportive of the resulting decisions than did participants in a control group. This result coincided with the participants in the study group perceiving the risks associated with the decision to be lower and the benefits higher. Responses from these participants also showed that they were more satisfied with the decision-making process than they were with the outcome of the decision itself. Therefore, it may be premature to view the objective of participatory decision-making approaches—and the risk communication efforts that discuss them—as a means of making risk policies more widely acceptable to the public at large. Rather, it may be better to view the benefits of these approaches in terms of their ability to help lead to higher quality decisions that are the product of more widely accepted decision processes.

Notes: This study examines how credibility affects the way people process information and how they subsequently perceive risk. Three conceptual areas are brought together in this analysis: the psychometric model of risk perception, Eagly and Chaiken's heuristic-systematic information processing model, and Meyer's credibility index. Data come from a study of risk communication in the circumstance of state health department investigations of suspected cancer clusters (five cases, N= 696). Credibility is assessed for three information sources: state health departments, citizen groups, and industries involved in each case. Higher credibility for industry and the state directly predicts lower risk perception, whereas high credibility for citizen groups predicts greater risk perception. A path model shows that perceiving high credibility for industry and state—and perceiving low credibility for citizen groups—promotes heuristic processing, which in turn is a strong predictor of lower risk perception. Alternately, perceiving industry and the state to have low credibility also promotes greater systematic processing, which consistently leads to perception of greater risk. Between a one-fifth and one-third of the effect of credibility on risk perception is shown to be indirectly transmitted through information processing.

Notes: Evidence that cell phone use while driving increases the risk of being involved in a motor vehicle crash has led policymakers to consider prohibitions on this practice. However, while restrictions would reduce property loss, injuries, and fatalities, consumers would lose the convenience of using these devices while driving. Quantifying the risks and benefits associated with cell phone use while driving is complicated by substantial uncertainty in the estimates of several important inputs, including the extent to which cell phone use increases a driver's risk of being involved in a crash, the amount of time drivers spend using cell phones (and hence their aggregate contribution to crashes, injuries, and fatalities), and the incremental value to users of being able to make calls while driving. Two prominent studies that have investigated cell phone use while driving have concluded that the practice should not be banned. One finds that the benefits of calls made while driving substantially exceed their costs while the other finds that other interventions could reduce motor vehicle injuries and fatalities (measured in terms of quality adjusted life years) at a lower cost. Another issue is that cell phone use imposes increased (involuntary) risks on other roadway users. This article revises the assumptions used in the two previous analyses to make them consistent and updates them using recent data. The result is a best estimate of zero for the net benefit of cell phone use while driving, a finding that differs substantially from the previous study. Our revised cost-effectiveness estimate for cell phone use while driving moves in the other direction, finding that the cost per quality adjusted life year increases modestly compared to the previous estimate. Both estimates are very uncertain.

Notes: Fish consumers may incur benefits and risks from eating fish. Health advisories issued by states, tribes, and other entities typically include advice about how to limit fish consumption or change other behaviors (e.g., fish cleaning or cooking) to reduce health risks from exposure to contaminants. Eating fish, however, may provide health benefits. Risk communicators and fish consumers have suggested the importance of including risk comparison information, as well as health risk-benefit comparisons in health advisory communications. To improve understanding about how anglers fishing in waters affected by health advisories may respond to such risk-risk or risk-benefit information, we surveyed Lake Ontario (NY, USA) anglers. We interviewed by telephone 4,750 anglers, 2,593 of which had fished Lake Ontario in the past 12 months and were sent a detailed mail questionnaire (1,245 responded). We posed questions varying the magnitude of health risks and health benefits to be gained by fish consumption, and varied the population affected by these risks and benefits (anglers, children, women of childbearing age, and unborn children). Respondents were influenced by health benefit and health risk information. When risks were high, most respondents would eat less fish regardless of the benefit level. When risks were low, the magnitude of change in fish consumption was related to level of benefit. Responses differed depending on the question wording order, that is, whether “risks” were posed before “benefits.” For a given risk-benefit level, respondents would give different advice to women of childbearing age versus children, with more conservative advice (eat less fish) provided to women of childbearing age. Respondents appeared to be influenced more strongly by risk-risk comparisons (e.g., risks from other foods vs. risks from fish) than by risk-benefit comparisons (e.g., risks from fish vs. benefits from fish). Risk analysts and risk communicators should improve efforts to include risk-risk and risk-benefit comparisons in communication efforts, and to clarify to whom the health risks and benefits from fish consumption may accrue.

Notes: Risk assessments include assumptions about sensitive subpopulations, such as the fraction of the general population that is sensitive and the extent that biochemical or physiological attributes influence sensitivity. Uncertainty factors (UF) account for both pharmacokinetic (PK) and pharmacodynamic (PD) components, allowing the inclusion of risk-relevant information to replace default assumptions about PK and PD variance (uncertainty). Large numbers of human organ donor samples and recent advances in methods to extrapolate in vitro enzyme expression and activity data to the intact human enable the investigation of the impact of PK variability on human susceptibility. The hepatotoxicity of trichloroethylene (TCE) is mediated by acid metabolites formed by cytochrome P450 2E1 (CYP2E1) oxidation, and differences in the CYP2E1 expression are hypothesized to affect susceptibility to TCE's liver injury. This study was designed specifically to examine the contribution of statistically quantified variance in enzyme content and activity on the risk of hepatotoxic injury among adult humans. We combined data sets describing (1) the microsomal protein content of human liver, (2) the CYP2E1 content of human liver microsomal protein, and (3) the in vitro Vmax for TCE oxidation by humans. The 5th and 95th percentiles of the resulting distribution (TCE oxidized per minute per gram liver) differed by approximately sixfold. These values were converted to mg TCE oxidized/h/kg body mass and incorporated in a human PBPK model. Simulations of 8-hour inhalation exposure to 50 ppm and oral exposure to 5 µg TCE/L in 2 L drinking water showed that the amount of TCE oxidized in the liver differs by 2% or less under extreme values of CYP2E1 expression and activity (here, selected as the 5th and 95th percentiles of the resulting distribution). This indicates that differences in enzyme expression and TCE oxidation among the central 90% of the adult human population account for approximately 2% of the difference in production of the risk-relevant PK outcome for TCE-mediated liver injury. Integration of in vitro metabolism information into physiological models may reduce the uncertainties associated with risk contributions of differences in enzyme expression and the UF that represent PK variability.

Notes: Foodborne illness represents a serious health hazard in the United States. Since foodborne illness can often be prevented by an individual's behavior, messages aimed at promoting safe food-handling behaviors should be a major tool to reduce the incidence of foodborne illness. This article argues that to achieve adoption of safe food-handling practices in the home, food-safety messages should both stimulate risk perceptions and promote self-efficacy, feelings that one can successfully enact recommended behaviors. A content analysis of nationally distributed food-safety messages questioned if messages incorporated these features. Since food-safety communicators operate in complex environments with multiple and sometimes competing objectives, this study also questioned if sponsorship of foodborne illness prevention messages was related to the amount of content designed to alter risk perceptions associated with foodborne illness. Results of the quantitative content analysis found that copywriters generally included content designed to stimulate risk perception about foodborne illness but virtually ignored self-efficacy needs of the audience. A marked difference in tendencies to stimulate risk perceptions was found based on sponsorship. Both in volume and proportion, results show that governmentally sponsored messages more aggressively attempted to heighten risk perceptions associated with foodborne illness than did messages sponsored by privately funded communicators.

Notes: Determining how to effectively operate security devices is as important to overall system performance as developing more sensitive security devices. In light of recent federal mandates for 100% screening of all checked baggage, this research studies the trade-offs between screening only selectee checked baggage and screening both selectee and non-selectee checked baggage for a single baggage screening security device deployed at an airport. This trade-off is represented using a cost model that incorporates the cost of the baggage screening security device, the volume of checked baggage processed through the device, and the outcomes that occur when the device is used. The cost model captures the cost of deploying, maintaining, and operating a single baggage screening security device over a one-year period. The study concludes that as excess baggage screening capacity is used to screen non-selectee checked bags, the expected annual cost increases, the expected annual cost per checked bag screened decreases, and the expected annual cost per expected number of threats detected in the checked bags screened increases. These results indicate that the marginal increase in security per dollar spent is significantly lower when non-selectee checked bags are screened than when only selectee checked bags are screened.