Risk assessment and comparisons: an introduction

Risk management of hydrogenation station PPP project based on 3D framework-A case study in China

Renewable hydrogen energy has received growing attention due to the energy shortage and increasing CO2 emissions. With these issues in mind, renewable hydrogen has become an important component of future energy systems in many countries, especially in the transportation sector. However, the shortage of hydrogenation station and the risks associated with their construction have become an urgent issue for the development of hydrogen energy transportation. To better implement the hydrogenation station project, a risk management framework is proposed for risk control. First, a comprehensive risk index system is developed, using a weighting method based on the G1 method and the C-OWA operator. Second, a grey fuzzy synthetic assessment method is applied to evaluate the risk based on the 3D risk assessment framework. Finally, risk is assigned to different participants and actionable measures are proposed. This paper summarizes the obstacles to the development of hydrogen energy transportation, highlights the potential of hydrogen energy development, and suggests workable solutions for the use of hydrogen energy in the future transportation industry.

The political economy of COVID-19

We assess the economic and health costs of COVID and policy responses to COVID. Based on initial estimates of health and economic costs, social distancing policies were justified, but these estimates now seem too high because of learning by doing. Significant differences in mortality rates across US states and countries can be explained by population density, climate, exposure, and policy. Regions that were able to contain the disease early have seen fewer deaths and lower economic losses. Some developing countries initially imposed drastic, costly measures, perhaps motivated by political economy. We also find that there has been underinvestment in prevention and mitigation that could have reduced the cost of adaptation and suggest that there is a lesson for climate change policies.

Assessment of Agricultural Drought Risk in the Lancang-Mekong Region, South East Asia

Natural disasters worldwide regularly impact on human activities. As a frequently occurring natural disaster, drought has adverse impacts on agricultural production. The Lancang-Mekong River is a transnational river running through China and five Southeast Asian countries and it is a vital water resource for irrigation in the region. Drought in the Lancang-Mekong Region (LMR) has occurred frequently in recent years. Assessing the risk of drought in the region is essential for rational planning of agricultural production and formulation of drought relief measures. In this study, an assessment of drought risk has been achieved by combining the hazard and vulnerability assessments for drought. The assessment of the drought hazard depends mainly on the standardized precipitation index (SPI). The assessment of drought vulnerability takes into account various indicators such as climatic factors (e.g., crop water stress index), soil factors (e.g., available water capacity), and irrigation factors (e.g., irrigation support). The results reveal that: (1) Drought distribution in the LMR is characterized by a spreading of the drought to countries along the middle and lower reaches of the Mekong River. Countries located in the middle and lower reaches of the Mekong River are more prone to drought. Laos, Thailand, and Cambodia are the regions with higher and high-drought risk levels. (2) The spatial distributions for the drought hazard and the drought vulnerability in the LMR exhibit significant differences as evidenced in the mapping results. High-hazard and high-vulnerability areas are mainly distributed in the middle LMR, and the middle to higher hazard areas and the middle to higher vulnerability areas are mainly distributed in the south-central LMR, while the low-hazard areas and the low-vulnerability areas are mainly in the north. (3) The majority of planting areas for sugarcane, rice, and cassava are located in the high-hazard areas. The distributions of drought-prone and high-hazard areas also correspond to the main agricultural areas in the LMR.

Environmental Risk Assessment for the Active Pharmaceutical Ingredient Mycophenolic Acid in European Surface Waters

An environmental risk assessment is presented for mycophenolic acid (MPA), an immunosuppressive pharmaceutical used for prevention of organ rejection, and its prodrug mycophenolate mofetil (MPM). Mycophenolic acid will not significantly adsorb to activated sludge. In activated sludge, ¹⁴ C-MPA attained >80% degradation, supporting an older environmental fate test with the same compound. Based on n-octanol/water distribution coefficient (log D_OW ) values of 2.28, 0.48, and ≤-1.54 at pH 5, 7, and 9, respectively, MPA is not expected to bioaccumulate. Sales amounts of MPA+MPM in Europe were used to derive predicted environmental concentrations (PECs) in surface waters; PECs were refined by including expected biodegradation in sewage treatment, average drinking water use, and average dilution of the effluents in the receiving waters per country. In addition, the exposure to pharmaceuticals in the environment (ePiE) model was run for 4 European catchments. The PECs were complemented with 110 measured environmental concentrations (MECs), ranging from below the limit of quantitation (<0.001 µg/L) to 0.656 µg/L. Predicted no-effect concentrations (PNECs) were derived from chronic tests with cyanobacteria, green algae, daphnids, and fish. The comparison of PECs and MECs with the PNECs resulted in a differentiated environmental risk assessment in which the risk ratio of PEC/PNEC or MEC/PNEC was <1 in most cases (mostly >90%), meaning no significant risk, but a potential risk to aquatic organisms in generally <10% of instances. Because this assessment reveals a partial risk, the following questions must be asked: How much risk is acceptable? and Through which measures can this risk be reduced? These questions are all the more important in view of limited alternatives for MPM and MPA and the serious consequences of not using them. Environ Toxicol Chem 2019;38:2259-2278. © 2019 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC.

Risk Prioritization in the Food Domain Using Deliberative and Survey Methods: Differences between Experts and Laypeople

This study examined how experts and laypeople using both a deliberative and a survey method prioritized 28 hazards related to food and everyday items. To enable them to make deliberative decisions, participants received detailed descriptions of the hazards. The participants prioritized the hazards before and after a group discussion, in which the group's average prioritization was discussed. The rankings of the hazards before and after the group discussion were highly correlated. However, laypeople and experts differed significantly in their rankings for 18 of the 28 hazards. Trust and confidence were important predictors for laypeople's risk rankings. To test the influence of the deliberative method (e.g., providing detailed information about each hazard), data from a second group of laypeople were collected with a no-information survey. This group did not receive specific information about the hazards. The risk rankings of the laypeople who received information were highly correlated with the risk rankings of laypeople who did not receive information. Overall, the results suggest that deliberative methods of risk-ranking or no-information survey methods with no information about hazards provide similar results among laypeople. The conclusion is that government agencies should not only base their risk prioritization on evidence from risk assessments but also need to consider laypeople's hazard rankings. This procedure may result in an efficient and publicly accepted risk management strategy.

A critical theoretic look at technical risk analysis

Technical risk analysis accomplishes the activities of risk identification, risk assessment and risk management by the use of scientific rationality. As an ac tivity of the political state, it also plays a role in managing the state's legitimacy problems. Critical theory can locate these two aspects of technical risk analysis in the context of a social theory as well as provide normative guidance for cor recting the deficiencies inherently associated with them. In particular, Haber mas's concepts of communicative rationality and the ideal speech situation have immediate ramifications of risk communication.

Lysosomal membrane response of the earthworm, Eisenia fetida, to arsenic species exposure in OECD soil

The NRRT assay was sensitive for toxicity assessment of inorganic arsenic pollution and it was affected more by As(iii) than by As(v).

Improving the quality of liver resection: a systematic review and critical analysis of the available prognostic models

BACKGROUND

Liver resection is considered to offer the only hope of cure for patients with liver malignancy. However, there are concerns about its safety, particularly in view of the increasing efficacy of less invasive strategies. No systematic review of prognostic research in liver resections has yet been performed.

METHODS

A systematic search identified articles published between 1999 and 2012 that performed a risk prediction analysis in patients undergoing liver resection. Studies were included if an outcome occurring within 90 days of surgery was identified, multivariable analysis performed and regression coefficients provided. The main endpoints were the outcomes and predictors chosen by the investigators, their definition, the performance and validity of the models, and the quality of the study as assessed using the QUIPS (quality in prognosis studies) tool.

RESULTS

A total of 91 studies were included. Eleven were prospective, but only two of these were registered. Twenty-eight endpoints were identified. These focused on postoperative morbidity or mortality, but many were redundant or ill defined and other relevant patient-reported outcomes were lacking. Predictors were not standardized, were poorly defined and overlapped. Only nine studies assessed the performance of their models and seven made an internal or temporal validation, but none reported an external validation or impact analysis. The median QUIPS score was 34 out of 50, indicating a high risk for bias.

CONCLUSION

Prognostic research in liver resection is still at the developmental stage.

Biomarker responses of earthworms (Eisenia fetida) exposured to phenanthrene and pyrene both singly and combined in microcosms

Microcosm studies were undertaken to relate biomarker responses to the toxicities in soil ecosystems contaminated by phenanthrene (Phe) and pyrene (Pyr), both singly and combined. Growth inhibition, enzyme activity, MDA content, sperm count, neutral-red retention time (NRRT) and annetocin and TCTP gene transcriptions were determined in earthworm Eisenia fetida exposed to Phe and Pyr, both singly and combined pollution in microcosm. Exposure to 0.5 and 2.5 mg kg(-1) Phe or 50 and 100 mg kg(-1) Pyr alone significantly decreased E. fetida growth, NRRT and sperm count. Two-way ANOVA analysis shows that the combination of these two compounds decreased growth, SOD activities, NRRT and sperm count synergistically, but increased the CAT activities and MDA content. The highest suppression rate of growth was 48.12%, the lowest levels of SOD activities and NRRT were 51.66% and 45.57% of the control, respectively. The highest increase in CAT activities and MDA content were 120.05% and 121.03% greater than that of the control when exposed to 0.5 (Phe)+100 (Pyr) mg kg(-1) soils. A clear dose-related response with exposure concentration was established for the NRRT. Real-time PCR shows that Phe and Pyr increased the expression levels of annetocin and TCTP gene synergistically. These results demonstrate that earthworms were under physiological stress at field dose of 0.5 (Phe)+100 (Pyr) mg kg(-1) soils. Phe and Pyr synergistically decreased sperm count and NRRT, but antagonistically caused changes in antioxidant enzyme activities to disrupt the detoxification functions and inhibit earthworm growth.

Effects of 1,2,4-trichlorobenzene on the enzyme activities and ultrastructure of earthworm Eisenia fetida

Adult Eisenia fetida earthworms were exposed to sub-lethal concentrations of 1,2,4-trichlorobenzene to assess the toxicity of contaminated soils. The LC₅₀ of 1,2,4-TCB at 7 and 14 d were 945±175 and 890±169 mg kg⁻¹. A lower dose of 1,2,4-TCB (25 mg g⁻¹) had stimulatory effects on SOD and AChE activities, but AChE activities were significantly inhibited at higher treatment levels (100 and 400 mg g⁻¹). SOD activities increased after 2, 7, and 14 d of exposure, but AChE activities were significantly inhibited at 400 mg/kg 1,2,4-TCB after 2, 7, and 14 d of exposure, and the inhibition rates were 25.41%, 28.65%, and 25.05%. Ultrastructural observation of the intestinal epithelium at three concentrations (control, 50, and 400 mg g⁻¹) revealed that the epicuticle, cuticle layer, and microvilli were damaged with increasing 1,2,4-TCB concentration. At 400 mg kg⁻¹, mitochondria were seriously injured and the smooth endoplasmic reticulum was seriously dilated.

Beyond dose assessment: using risk with full disclosure of uncertainty in public and scientific communication

Evaluations of radiation exposures of workers and the public traditionally focus on assessments of radiation dose, especially annual dose, without explicitly evaluating the health risk associated with those exposures, principally the risk of radiation-induced cancer. When dose is the endpoint of an assessment, opportunities to communicate the significance of exposures are limited to comparisons with dose criteria in regulations, doses due to natural background or medical x-rays, and doses above which a statistically significant increase of disease has been observed in epidemiologic studies. Risk assessment generally addresses the chance (probability) that specific diseases might be induced by past, present, or future exposure. The risk of cancer per unit dose will vary depending on gender, age, exposure type (acute or chronic), and radiation type. It is not uncommon to find that two individuals with the same effective dose will have substantially different risks. Risk assessment has shown, for example, that: (a) medical exposures to computed tomography scans have become a leading source of future risk to the general population, and that the risk would be increased above recently published estimates if the incidence of skin cancer and the increased risk from exposure to x-rays compared with high-energy photons were taken into account; (b) indoor radon is a significant contributor to the baseline risk of lung cancer, particularly among people who have never smoked; and (c) members of the public who were exposed in childhood to I in fallout from atmospheric nuclear weapons tests and were diagnosed with thyroid cancer later in life would frequently meet criteria established for federal compensation of cancers experienced by energy workers and military participants at atmospheric weapons tests. Risk estimation also enables comparisons of impacts of exposures to radiation and chemical carcinogens and other hazards to life and health. Communication of risk with uncertainty is essential for reaching informed consent, whether communicating to a larger community debating the tradeoffs of risks and benefits of an action that involves radiation exposure or communicating at the level of a physician and patient.

Effects of phenanthrene on the mortality, growth, and anti-oxidant system of earthworms (Eisenia fetida) under laboratory conditions

To assess the toxic effects of phenanthrene on earthworms, we exposed Eisenia fetida to artificial soils supplemented with different concentrations (0.5, 2.5, 12.5, mgkg(-1) soil) of phenanthrene. The residual phenanthrene in the soil, the bioaccumulation of phenanthrene in earthworms, and the subsequent effects of phenanthrene on growth, anti-oxidant enzyme activities, and lipid peroxidation (LPO) were determined. The degradation rate of low concentrations of phenanthrene was faster than it was for higher concentrations, and the degradation half-life was 7.3d (0.5 mgkg(-1)). Bioaccumulation of phenanthrene in the earthworms decreased the phenanthrene concentration in soils, and phenanthrene content in the earthworms significantly increased with increasing initial soil concentrations. Phenanthrene had a significant effect on E. fetida growth, and the 14-d LC(50) was calculated as 40.67 mgkg(-1). Statistical analysis of the growth inhibition rate showed that the concentration and duration of exposure had significant effects on growth inhibition (p<0.001). Superoxide dismutase (SOD) activity increased at the beginning (2 and 7d) and decreased in the end (14 and 28 d). Catalase (CAT) activity in all treatments was inhibited from 1 to 14 d of exposure. However, no significant perturbations in malondialdehyde (MDA) content were noted between control and phenanthrene-treated earthworms except after 2d of exposure. These results revealed that bioaccumulation of phenanthrene in E. fetida caused concentration-dependent, sub-lethal toxicity. Growth and superoxide dismutase activity can be regarded as sensitive parameters for evaluating the toxicity of phenanthrene to earthworms.

Primer: Demystifying risk--understanding and communicating medical risks

Assessments of risk are a critical part of the practice of evidence-based medicine. Comprehension of various risk measures, such as absolute risk, relative risk, attributable risk, odds ratio, and hazard ratio, is essential to understand the medical literature, and to communicate health risks effectively. Complex risk measures, including number needed to treat and survival estimates that are adjusted for competing risks, are often misunderstood. Communication of these concepts to patients can be a challenge. The patient's perception of risk stems not only from the way risks are stated, but also from family history, personal experiences, cultural norms, and beliefs. A multifaceted approach to risk communication that uses both qualitative and quantitative assessments of risk, and addresses the timing and permanence of risks, is necessary to ensure the patient understands the potential risks. Successful communication involves interaction with the patient to understand the patient's perspective and to aid in personalized decision-making. In the face of uncertainty, making a provisional decision with a plan to review it later can be a good strategy. Verifying the patient's comprehension can help ensure that the decisions reached are informed and acceptable.

Is there a real risk of transmitting variant Creutzfeldt-Jakob disease by donor sperm insemination?

Although >99% of cases of Creutzfeldt-Jakob disease (CJD) are caused by spontaneous or inherited mutations in the prion protein, 'variant' CJD (vCJD) arose from dietary exposure to meat products infected with the bovine spongiform encephalopathy prion. While European and Canadian sperm donor candidates are rejected for significant CJD risk factors, American sperm donors are managed like blood donors (excluding all men who spent > or =3 months in the UK during 1980-1996 or > or =5 years in Europe since 1980), even though no evidence exists for sexual transmission of prion disease. This study surveyed international experts on either prions/prion disease or donor sperm/cryobanking as to the risk of vCJD transmission via semen/donor spermatozoa (45/104 replied). Consensus expert opinion was that the risk of transmission was <1:10,000,000, even for UK men, hence ultra-conservative risk avoidance would have minimal impact on public safety. Defining 'high vCJD risk' should be based on knowledge rather than fear, and due caution founded upon quantifying real risks rather than avoiding theoretical risks. Women seeking treatment using donor spermatozoa should be allowed to judge the negligible risk of vCJD infection in comparison with acceptable everyday risks, and given the choice of accepting spermatozoa from donors screened according to European-style criteria.

Biomarkers responses of the earthworm Eisenia fetida to acetochlor exposure in OECD soil

To examine the potential of a suite of biomarkers as early warning indicators of environmental pollution, sperm count, neutral red retention time (NRRT) and DNA damage were measured in earthworm Eisenia fetida exposed to increasing concentrations of acetochlor in OECD soil. The neutral red retention time of earthworms coelomocytes was sensitive to acetochlor pollution, and decreased significantly when the concentration was more than 10mgkg(-1) after 30 and 60 days of exposure (P<0.05). The reduced neutral red retention time correlated with the soil acetochlor residual. Sperm count decreased significantly at the concentrations of 40 and 80mgkg(-1) after 15 days of exposure (P<0.05). The DNA damage of earthworms coelomocytes increased significantly after 30 days of exposure at the highest concentration (80mgkg(-1); P<0.05). Earthworms were under physiological stress at field dose of acetochlor (10mgkg(-1)). Higher concentrations of acetochlor caused sperm count decrease and DNA damage of earthworms. Such a suite of biomarkers could serve as indicators of the health of the soil environment and to evaluate the toxicity of acetochlor on earthworms or as a means of monitoring soil acetochlor pollution.

Physician reporting of medically impaired drivers

Emergency physicians frequently encounter patients whose medical conditions represent a risk of loss of control while driving, e.g., epilepsy and diabetes. In certain states, physicians are under a legal obligation to report such drivers to the motor vehicular authorities. To determine the uniformity of legislated reporting requirements for physicians caring for patients whose medical conditions represent an automotive hazard, we conducted a survey of Department of Motor Vehicles (DMV) legal departments of all the states in the United States for the academic year 1999-2000 regarding physician reporting of patients with medical conditions that might predispose them to a motor vehicle crash (MVC) and compared the results to a similar study done in 1986. Six (12%) of the states had mandatory reporting laws, 25 (49%) had permissive reporting laws, and 20 (39%) had no laws regarding physician reporting. There was a significant difference between the distribution of laws by year. There was no uniformity on a national level concerning such legislation.

Quantitative risk analysis of oil storage facilities in seismic areas

Quantitative risk analysis (QRA) of industrial facilities has to take into account multiple hazards threatening critical equipment. Nevertheless, engineering procedures able to evaluate quantitatively the effect of seismic action are not well established. Indeed, relevant industrial accidents may be triggered by loss of containment following ground shaking or other relevant natural hazards, either directly or through cascade effects ('domino effects'). The issue of integrating structural seismic risk into quantitative probabilistic seismic risk analysis (QpsRA) is addressed in this paper by a representative study case regarding an oil storage plant with a number of atmospheric steel tanks containing flammable substances. Empirical seismic fragility curves and probit functions, properly defined both for building-like and non building-like industrial components, have been crossed with outcomes of probabilistic seismic hazard analysis (PSHA) for a test site located in south Italy. Once the seismic failure probabilities have been quantified, consequence analysis has been performed for those events which may be triggered by the loss of containment following seismic action. Results are combined by means of a specific developed code in terms of local risk contour plots, i.e. the contour line for the probability of fatal injures at any point (x, y) in the analysed area. Finally, a comparison with QRA obtained by considering only process-related top events is reported for reference.

Residential radon in Canada: an uncertainty analysis of population and individual lung cancer risk

Following a comprehensive evaluation of the health risks of radon, the U.S. National Research Council (US-NRC) concluded that the radon inside the homes of U.S. residents is an important cause of lung cancer. To assess lung cancer risks associated with radon exposure in Canadian homes, we apply the new (US-NRC) techniques, tailoring assumptions to the Canadian context. A two-dimensional uncertainty analysis is used to provide both population-based (population attributable risk, PAR; excess lifetime risk ratio, ELRR; and life-years lost, LYL) and individual-based (ELRR and LYL) estimates. Our primary results obtained for the Canadian population reveal mean estimates for ELRR, PAR, and LYL are 0.08, 8%, and 0.10 years, respectively. Results are also available and stratified by smoking status (ever versus never). Conveniently, the three indices (ELRR, PAR, and LYL) reveal similar output uncertainty (geometric standard deviation, GSD approximately 1.3), and in the case of ELRR and LYL, comparable variability and uncertainty combined (GSD approximately 4.2). Simplifying relationships are identified between ELRR, LYL, PAR, and the age-specific excess rate ratio (ERR), which suggest a way to scale results from one population to another. This insight is applied in scaling our baseline results to obtain gender-specific estimates, as well as in simplifying and illuminating sensitivity analysis.

Evaluation of a visual risk communication tool: effects on knowledge and perception of blood transfusion risk

BACKGROUND

Effective risk communication in transfusion medicine is important for health-care consumers, but understanding the numerical magnitude of risks can be difficult. The objective of this study was to determine the effect of a visual risk communication tool on the knowledge and perception of transfusion risk.

STUDY DESIGN AND METHODS

Laypeople were randomly assigned to receive transfusion risk information with either a written or a visual presentation format for communicating and comparing the probabilities of transfusion risks relative to other hazards. Knowledge of transfusion risk was ascertained with a multiple-choice quiz and risk perception was ascertained by psychometric scaling and principal components analysis.

RESULTS

Two-hundred subjects were recruited and randomly assigned. Risk communication with both written and visual presentation formats increased knowledge of transfusion risk and decreased the perceived dread and severity of transfusion risk. Neither format changed the perceived knowledge and control of transfusion risk, nor the perceived benefit of transfusion. No differences in knowledge or risk perception outcomes were detected between the groups randomly assigned to written or visual presentation formats.

CONCLUSION

Risk communication that incorporates risk comparisons in either written or visual presentation formats can improve knowledge and reduce the perception of transfusion risk in laypeople.

Injury related risk behavior--a study of Australian skydivers

Risk taking behaviour has been identified as an important host-related determinant of injury in young adults. The aim of this study is to clarify the relationship between the two key elements of risk taking behaviour--ie, risk assessment and risk acceptance--in participants of a high risk sporting activity. Skydivers registered with the Australian Parachute Federation were sampled at several jump meetings held at three 'drop-zones' in North Eastern Australia. A cross sectional survey of 215 skydivers ascertained each subject's risk assessment of each of nine hypothetical sky diving scenes and whether or not they would jump in the described conditions. Variables which independently predicted an individual's risk assessment were age group (p < 0.05). gender (p < 0.05) and scene details (p < 0.001). Risk assessment was found to be a statistically significant predictor of the decision to jump, with a 22% decrease in the odds of jumping with every unit increase in risk assessment (OR = 0.78: 95% CI: 0.76, 0.80). Gender was also found to be a statistically significant predictor of the decision to jump, with males being 19% more likely to jump than females, after controlling for age, experience, currency and risk assessment (OR = 1. 19: 95% CI; 1.04, 1.38). The importance of these results is that, by quantifying the relationship between two key elements of risk taking behaviour and several important host factor determinants, they facilitate more informed discussion about the possible role of risk taking behaviour in the causation of injury.

Print media coverage of risk-risk tradeoffs associated with West Nile encephalitis and pesticide spraying

When mosquito-borne West Nile virus emerged in the United States in 1999 and triggered pesticide spraying, society was faced with a controversy over an important risk-risk tradeoff-the risks of pesticide exposure versus those of West Nile encephalitis. Effective public communication about risk-risk tradeoffs is important because it can assist individuals and society in investing resources optimally. This study examined how effectively major North American print media in the year 2000 provided information on this risk-risk tradeoff. My colleagues and I found that the print media were generally ineffective in providing precise information about pesticide risks and in comparing risks of pesticide exposure with those of West Nile encephalitis. The media were also ineffective in mentioning the efficacy of pesticide spraying or comparing the economic costs of pesticide spraying with those of West Nile encephalitis. We suggest that greater effort in collecting and reporting precise risk information, fostering more active relationships between journalists and scientists/public health professionals, and recognizing biases resulting from preconceptions can help improve reporting by the print media and public health agencies on risk-risk tradeoffs associated with emerging insect-borne infectious diseases. These efforts could help improve public health by improving decision making related to the control of insect-borne diseases.

Genetic testing for lung cancer risk: if physicians can do it, should they?

Advances in genetics have increased our ability to assess an individual's genetic risk for disease. There is a hypothesis that genetic test results will motivate high-risk individuals to reduce harmful exposures, to increase their surveillance for disease, or to seek preventive treatments. However, genetic testing for genes associated with an increased risk of lung cancer would not change physicians' recommendations regarding smoking cessation. Limited studies suggest that test results that demonstrate an increased risk of lung cancer do not improve smoking cessation success. These test results may even distort an individual's risk perceptions. Before recommending genetic testing to assess risk for disease, physicians need to consider whether knowledge about genetic susceptibility will alter patient management.

A new approach to risk evaluation and management: risk-based, precaution-based, and discourse-based strategies

Our concept of nine risk evaluation criteria, six risk classes, a decision tree, and three management categories was developed to improve the effectiveness, efficiency, and political feasibility of risk management procedures. The main task of risk evaluation and management is to develop adequate tools for dealing with the problems of complexity, uncertainty. and ambiguity. Based on the characteristics of different risk types and these three major problems, we distinguished three types of management--risk-based, precaution-based, and discourse-based strategies. The risk-based strategy--is the common solution to risk problems. Once the probabilities and their corresponding damage potentials are calculated, risk managers are required to set priorities according to the severity of the risk, which may be operationalized as a linear combination of damage and probability or as a weighted combination thereof. Within our new risk classification, the two central components have been augmented with other physical and social criteria that still demand risk-based strategies as long as uncertainty is low and ambiguity absent. Risk-based strategies are best solutions to problems of complexity and some components of uncertainty, for example, variation among individuals. If the two most important risk criteria, probability of occurrence and extent of damage, are relatively well known and little uncertainty is left, the traditional risk-based approach seems reasonable. If uncertainty plays a large role, in particular, indeterminacy or lack of knowledge, the risk-based approach becomes counterproductive. Judging the relative severity of risks on the basis of uncertain parameters does not make much sense. Under these circumstances, management strategies belonging to the precautionary management style are required. The precautionary approach has been the basis for much of the European environmental and health protection legislation and regulation. Our own approach to risk management has been guided by the proposition that any conceptualization of the precautionary principle should be (1) in line with established methods of scientific risk assessments, (2) consistent and discriminatory (avoiding arbitrary results) when it comes to prioritization, and (3) at the same time, specific with respect to precautionary measures, such as ALARA or BACT, or the strategy of containing risks in time and space. This suggestion does, however, entail a major problem: looking only to the uncertainties does not provide risk managers with a clue about where to set priorities for risk reduction. Risks vary in their degree of remaining uncertainties. How can one judge the severity of a situation when the potential damage and its probability are unknown or contested? In this dilemma, we advise risk managers to use additional criteria of hazardousness, such as "ubiquity versibility," and "pervasiveness over time," as proxies for judging severity. Our approach also distinguishes clearly between uncertainty and ambiguity. Uncertainty refers to a situation of being unclear about factual statements; ambiguity to a situation of contested views about the desirability or severity of a given hazard. Uncertainty can be resolved in principle by more cognitive advances (with the exception of indeterminacy). ambiguity only by discourse. Discursive procedures include legal deliberations as well as novel participatory approaches. In addition, discursive methods of planning and conflict resolution can be used. If ambiguities are associated with a risk problem, it is not enough to demonstrate that risk regulators are open to public concerns and address the issues that many people wish them to take care ot The process of risk evaluation itself needs to be open to public input and new forms of deliberation. We have recommended a tested set of deliberative processes that are, at least in principle, capable of resolving ambiguities in risk debates (for a review, see Renn, Webler, & Wiedemaun. 1995). Deliberative processes are needed, however, for ail three types of management. Risk-based management relies on epistemiological, uncertainty-based management on reflective, and discourse-based management on participatory discourse forms. These three types of discourse could be labeled as an analytic-deliberative procedure for risk evaluation and management. We see the advantage of a deliberative style of regulation and management in a dynamic balance between procedure and outcome. Procedure should not have priority over the outcome; outcome should not have priority over the procedure. An intelligent combination of both can elaborate the required prerequisites of democratic deliberation and its substantial outcomes to enhance the legitimacy of political decisions (Guttman & Thompson, 1996; Bohman, 1997. 1998).

Periodontal risk assessment, diagnosis and treatment planning

The prevention and treatment of the periodontal diseases is based on accurate diagnosis, reduction or elimination of causative agents, risk management and correction of the harmful effects of disease. Prominent and confirmed risk factors or risk predictors for periodontitis in adults include smoking, diabetes, race, P. gingivalis, P. intermedia, low education, infrequent dental attendance and genetic influences. Several other specific periodontal bacteria, herpesviruses, increased age, male, sex, depression, race, traumatic occlusion and female osteoporosis in the presence of heavy dental calculus have been shown to be associated with loss of periodontal support and can be considered to be risk indicators of periodontitis. The presence of furcation involvement, tooth mobility, and a parafunctional habit without the use of a biteguard are associated with a poorer periodontal prognosis following periodontal therapy. An accurate diagnosis can only be made by a thorough evaluation of data that have been systematically collected by: 1) patient interview, 2) medical consultation as indicated, 3) clinical periodontal examination, 4) radiographic examination, and 5) laboratory tests as needed. Clinical signs of periodontal disease such as pocket depth, loss of clinical attachment and bone loss are cumulative measures of past disease. They do not provide the dentist with a current assessment of disease activity. In an attempt to improve the ability to predict future disease progression, several types of diagnostic tests have been studied, including host inflammatory products and mediators, enzymes, tissue breakdown products and subgingival temperature. In general, the usefulness of these tests for predicting future disease activity remains to be established in terms of sensitivity, specificity and predictive value. Although microbiological analysis of subgingival plaque is not necessary to diagnose and treat most patients with periodontitis, it is helpful when treating patients with unusual forms of periodontal disease such as early-onset, refractory and rapidly progressive disease. There appears to be a strong genetic component in some types of periodontal disease and genetic testing for disease susceptibility has potential for future use, but more research is needed to determine its utility for use in clinical practice. Treatment of the periodontal diseases may be divided into four phases: systemic, hygienic, corrective and maintenance or supportive periodontal therapy. Regardless of the type of treatment provided, periodontal therapy will fail or will be less effective in the absence of adequate supportive periodontal therapy.

Risk communication, the West Nile virus epidemic, and bioterrorism: responding to the communication challenges posed by the intentional or unintentional release of a pathogen in an urban setting

The intentional or unintentional introduction of a pathogen in an urban setting presents severe communication challenges. Risk communication--a science-based approach for communicating effectively in high-concern situations--provides a set of principles and tools for meeting those challenges. A brief overview of the risk communication theoretical perspective and basic risk communication models is presented here, and the risk communication perspective is applied to the West Nile virus epidemic in New York City in 1999 and 2000 and to a possible bioterrorist event. The purpose is to provide practical information on how perceptions of the risks associated with a disease outbreak might be perceived and how communications would be best managed.

An analysis of the concept of risk

The meaning of the word "risk" has changed throughout history. Once a neutral term, risk has come to represent a combination of probability and something adverse or dangerous. Phenomena that were previously referred to as hazards, dangers, or uncertainties are now labeled as risks. Although risk touches every aspect of health and human welfare, the dimensions of risk as conceptualized in the fields of epidemiology, nursing science, medical science, and lay health are qualitatively different. Risk has not been examined as a concept in nursing literature or research, although risk and related terms are defined in a few nursing textbooks. Using the evolutionary method of concept analysis, risk is examined as a concept. This analysis was undertaken to define and clarify the concept and dimensions of risk as they relate to risk for disease. A sound understanding of risk as a concept is critical for developing an empirical knowledge base in nursing and directing nursing research examining issues related to risk for developing diseases such as cancer.

Calculating the Chances

Should We Risk It? Exploring Environmental, Health, and Technological Problem Solving. Daniel M. Kammen and David M. Hassenzahl. Princeton University Press, Princeton, NJ, 1999. 424 pp. $39.50, £23.95. ISBN 0-691-00426-9.

Kammen and Hassenzahl explore the nature and methods of risk analysis--and the relationship between science and policy--by critically examining and clearly explaining selected problems ranging from cancer susceptibility to airplane flights.

Predictive testing for Huntington's disease: II. Qualitative findings from a study of uptake in South Wales

Semi-structured interviews were conducted with a cohort of 22 test applicants who requested Huntington's disease (HD) predictive testing in South Wales, and a random sample of 32 non-requesters, drawn from the South Wales HD register. Apart from identifying differences between the groups, the study afforded the opportunity to listen, at length, to at-risk individuals' accounts of living at risk and their thoughts about predictive testing and genetic services. Emergent themes included difficulties in family communication and the uncertainties inherent in being at risk and undergoing testing. Important factors in decision making about testing were: moral imperatives to clarify one's genetic status: views about the controllability of the future; family attitudes and norms; and the impact of a test result on family members. At-risk individuals' perceptions of the genetics service were that contact with the service would result in pressure to be tested and a need for test applicants to present a favourable view of coping capacities to secure testing. In addition, there was an expectation of ongoing contact with HD families at the initiative of the service providers. Implications of the findings for the way in which predictive testing services are structured and introduced to the at-risk population are discussed.

Meat inspection: an overview of present practices and future trends

This is a review of meat inspection literature, its history, current concerns and needs for the future. The value and limitations of meat inspection are discussed, along with the possible modifications or changes that are being developed to modernize an increasingly outdated method of safeguarding public health. The potential of on-farm risk assessment of slaughter animals and the practical considerations that need to be overcome are outlined. The needs of the consumer and subsequent challenges to the meat and farming industry are proposed as the driving force behind the changes occurring in veterinary public health. The current risk to consumers, from such microbial pathogens as Salmonella, Escherichia coli O157:H7 and Campylobacter infection, are highlighted.

"Environmental justice": the central role of research in establishing a credible scientific foundation for informed decision making

Although much of the evidence is anecdotal and circumstantial, there are mounting concerns that environmental health risks are borne disproportionately by members of the population who are poor and nonwhite. We examine the central role of environmental health research in defining the dimensions of the problem, understanding its causes, and identifying solutions. Environmental health sciences, including epidemiology, exposure analysis. pharmacokinetics, toxicology, and surveillance monitoring, must be employed to determine the extent to which society has achieved "equity" and "justice" in safeguarding the health and safety of its citizens. By improving our ability to identify, evaluate, prevent, and/or reduce risks for all members of society, environmental health research can contribute directly to fair and equitable protection for everyone, regardless of age, ethnicity, gender, race, or socioeconomic status.