bluuebunny/crossref_metadata_2025 huggingface dataset:
Predictors of Compliance with Naltrexone Among Alcoholics
Authors: Rohsenow Damaris J. , Colby Suzanne M. , Monti Peter M. , Swift Robert M. , Martin Rosemarie A. , Mueller Timothy I. , Gordon Alan , Eaton Cheryl A.
Published: May 2006

Objective:

Naltrexone has been found to be an effective adjunct to treatment to reduce the rate of drinking among alcoholics. However, adherence to the medication has been of considerable concern; the high rates of noncompliance with the medication limits the benefits that could potentially be realized from this pharmacotherapy. Knowledge of predictors of noncompliance could result in interventions targeted at these variables.

Method:

Participants were 128 alcohol‐dependent patients who participated in a clinical placebocontrolled trial of naltrexone. Upon discharge from a 1‐ to 2‐week partial hospital program, patients were randomly placed into 12 weeks of naltrexone (50 mg/day) or placebo (n= 64 per condition). Patients met with a physician and a research assistant weekly for 4 weeks then biweekly for 8 weeks.

Results:

Compliance (number of days taking medication) was not predicted by demographic or pretreatment alcohol use variables. Number and severity of side effects in the first week, particularly nausea and fatigue, predicted early termination. Compliance was not predicted by commitment to abstinence or self‐efficacy about abstinence, but was greater among patients who believed more strongly that the medication would help them stay sober. Compliance was not predicted by general level of urge to drink during the first week on medication but compliance was greater among those with a higher urge to drink in response to alcohol stimuli in the laboratory.

Conclusions:

Implications for approaches to increase compliance include reducing side effects and increasing patients’beliefs in the efficacy of naltrexone.
Ethanol Exposure Enhances Apoptosis Within the Testes
Authors: Zhu Qianlong , Meisinger Jeremy , Emanuele Nicholas V. , Emanuele Mary Ann , LaPaglia Nancy , Van Thiel David H.
Published: May 2006

Background:

Chronic ethanol abuse causes testicular atrophy and male infertility in alcoholic men. It is well known that ethanol exposure disrupts the hypothalamic‐pituitary‐gonadal axis, adversely affects the secretory function of Sertoli cells, and produces oxidative stress within the testes. It is still not clear what cellular mechanisms are responsible for the morphologic alteration of the testes that results in a reduction of testicular mass as a consequence of ethanol exposure. The hypothesis tested was that ethanol enhances apoptosis of testicular germ cells.

Methods:

In the experiments of chronic ethanol exposure, male Sprague Dawley® rats (Harlan Sprague Dawley, Inc., Indianapolis, IN) were fed Liber‐Decarlie liquid diet for 9 weeks. In the experiments of acute ethanol exposure, a small volume of 20% ethanol solution was administered by intratesticular injection. Both 3′‐end labeling of isolated testicular deoxyribonucleic acid (DNA) and labeling of apoptotic cells in situ by the terminal deoxynucleotidyl transferase‐mediated deoxyuridine 5′‐triphosphate nick end‐labeling method were used to determine apoptosis rates within the testes. The expression of proteins involved in apoptosis was assessed by reverse transcription‐polymerase chain reaction and by Western blotting.

Results:

The testes of rats that were fed an ethanol‐containing liquid diet had more testicular DNA fragmentation than did those of animals that were fed an isocaloric control diet. Ethanol increased the number of apoptotic spermatogonia as well as spermatocytes. Direct intratesticular injections of ethanol solution enhanced testicular DNA fragmentation, suggesting an increase in apoptosis. Moreover, Fas ligand levels were increased within the testes of rats that were chronically fed ethanol. In vitro, ethanol treatment of cultured Sertoli cells enhanced the production of Fas ligand. In addition, testicular levels of p53 messenger ribonucleic acid were increased in rats that were chronically fed ethanol.

Conclusions:

All of these observations suggest that ethanol enhances testicular germ cell apoptosis.
Neuropsychological Deficits in Sober Alcoholics: Influences of Chronicity and Recent Alcohol Consumption
Authors: Beatty William W. , Tivis Rick , Stott Heather D. , Nixon Sara Jo , Parsons Oscar A.
Published: May 2006

Background:

The relationships between severity of neuropsychological (NP) deficits and quantity and duration of alcoholic drinking remain controversial. Eckardt et al. (1998) proposed that NP deficits can be observed only if chronicity of alcohol abuse equals or exceeds 10 years. In this study we tested the hypothesis of Eckardt et al. and reexamined the relationship of NP performance and alcohol consumption.

Methods:

One hundred sixty‐two alcoholics and 165 controls completed a NP test battery at least 3 weeks after the alcoholics attained sobriety. Chronicity varied from 4 to 9 years for 55 alcoholics and from 10 to 33 years for the remaining 107.

Results:

Compared to controls, both groups of alcoholics were impaired on the Shipley Vocabulary and Abstraction tests and on two versions of the Digit Symbol test, but there was no difference between the two alcoholic groups on any measure. Regression analyses that controlled for age and education showed that chronicity predicted less than 0.5% of the variance on NP measures. By contrast, a measure of recent alcohol consumption, the Quantity‐Frequency Index, contributed significantly (approximately 5% of the variance) to the prediction of alcoholics’NP performance.

Conclusions:

These data provide weak support for a dose effect relationship between degree of NP impairment and level of alcoholic drinking in the past 6 months but no evidence for an influence of chronicity.
Polyenylphosphatidylcholine Protects Against Alcohol but Not Iron‐Induced Oxidative Stress in the Liver
Authors: Aleynik Semyon I. , Leo Maria Anna , Aleynik Maria K. , Lieber Charles S.
Published: May 2006

Background:

We reported before that, in baboons, the alcohol‐induced oxidative stress in the liver is associated with depletion of dilinoleoylphosphatidylcholine [the major component of polyenylphosphati‐dylcholine (PPC)] and that both can be corrected by the administration of PPC, but we did not determine whether this protection extended to iron‐induced oxidative stress.

Methods:

To compare the effects of PPC on alcohol‐ and iron‐induced hepatic oxidative stress, 56 Sprague Dawley® male rats were pair‐fed nutritionally adequate liquid diets containing ethanol (36% of energy) or isocaloric carbohydrate and PPC (3 mg/ml) or safflower oil (2.73 mg/ml), with or without 5 mg/ml carbonyl iron for 2 months. Markers of oxidative stress (4‐hydroxynonenal and reduced glutathione), antioxidants (vitamin E, ubiquinol‐9, and ubiquinol‐10), and phosphatidylcholine (PC) species were assessed by HPLC and/or gas chromatography/mass spectrometry.

Results:

Alcohol feeding increased hepatic 4‐hydroxynonenal 3‐fold and decreased glutathione by 19%, ubiquinol‐10 by 53%, and PC species containing arachidonate (palmitoyl‐ and stearoylarachidonoylphosphatifidylcholines by 24% and 21%, respectively) and total phospholipids by 14%. PPC feeding prevented the rise of 4‐hydroxynonenal, restored glutathione, and increased the hepatic content of dilinolcoylphosphatidylcholine and of some other PC carrying polyunsaturated fatty acids. Administration of iron alone increased hepatic iron, doubled 4‐hydroxynonenal and glutathione, whereas it decreased vitamin E, ubiquinol‐9, total phospholipids, and several polyunsaturated PC. Alcohol given with iron further exacerbated the hepatic oxidative stress, as documented by the increase of 4‐hydroxynonenal and the decrease in glutathione and ubiquinols‐10. PPC did not prevent this oxidative stress, although it increased hepatic glutathione. Hepatic dilinoleoylphosphatidylcholine content was comparable with and without dietary iron.

Conclusions:

PPC prevents the alcohol‐induced oxidative stress but only in the absence of iron overload.
Analysis of Heritability of Hormonal Responses to Alcohol in Twins: Beta‐Endorphin as a Potential Biomarker of Genetic Risk for Alcoholism
Authors: Froehlich J. C. , Zink R. W. , Li T.‐K. , Christian J. C.
Published: May 2006

Background:Hormonal responses to alcohol have been reported to differ in subjects with and without a family history of alcoholism which suggests that alcohol‐induced hormonal changes might be used to identify individuals who are at elevated genetic risk for developing alcoholism. However, before a biological response can be used as a marker of genetic risk for disease, it must first be demonstrated that the response is, in fact, heritable. The present study was designed to determine whether hormonal responses to alcohol are heritable.

Methods:The adrenocorticotropic hormone (ACTH), beta‐endorphin (β‐E), cortisol (CORT), and prolactin (PRL) responses to alcohol were examined in male and female identical (monozygotic or MZ) and fraternal (dizygotic or DZ) twin pairs. Male subjects consumed 0.35g ethanol/kg body weight (BW) and female consumed 0.325 g ethanol/kg BW in each of two alcohol drinking sessions administered 1 hr apar (total dose of 0.7 g/kg BW in males and 0.65 g/kg BW in females). Plasma hormone content was analyzed in samples collected before (resting conditions) and at 15, 60, 75, 120, 180, and 240 min after onset of drinking. Hormonal responses to alcohol were examined with twin analyses using the TWINAN90 program. A separate analysis was performed for each of the four hormones. A subset of subjects from each zygosity was seen on two separate occasions to establish retest reliability. Heritability of hormonal responses to alcohol was estimated using the intraclass correlation approach before and after removing the contribution of covariates that have the potential of influencing the plasma levels of these hormones.

Results:Resting plasma levels of all four hormones were within the expected range, and the β‐E, ACTH, and PRL responses to the alcohol challenge evidenced good test‐retest reliability. Of the four hormones examined, the only one that showed significant heritability after alcohol drinking was β‐E. Heritability estimates were not altered for any of the four hormones after removal of the variance contributed by covariates, such as gender and age.

Conclusions:Taken together with other recent findings, the results suggest that the β‐E response to alcohol may represent a new biomarker that can be used to identify individuals who are at elevated genetic risk for developing alcoholism.
Ethanol Suppresses NK Cell Activation by Polyinosinic‐Polycytidylic Acid (Poly I:C) in Female B6C3F1 Mice: Role of Endogenous Corticosterone
Authors: Collier Stephanie D. , Wu Wen‐Jun , Pruett Stephen B.
Published: May 2006

Background: Acute administration of EtOH suppresses basal NK cell lytic function in mice, and this suppression is caused, in part, by neuroendocrine mediators induced by EtOH. There is also evidence that a smaller part of the suppression is caused by direct action of EtOH. However, activation of NK cells to higher levels of lytic activity may be more important than basal NK cell lytic function in resistance to cancer or infectious agents. Therefore, the study described here examined the effects of acute EtOH exposure on activation of NK cells by polyinosinic‐polycytidilic acid (poly I:C).

Methods: Ethanol was administered by gavage as a 32% solution in water, and poly I:C was administered to activate NK cells. NK cell activity was measured using a standard 4 hr 51Cr release assay with YAC‐1 tumor cells. The effects of corticosterone were evaluated by administration of a glucocorticoid antagonist (RU 486) or a dosage of corticosterone previously shown to induce similar blood levels as treatment with EtOH.

Results: EtOH at 5–7 g/kg suppressed poly I:C‐induced increases in NK cell lytic activity, and at least the lower end of this dosage range yields bloud EtOH levels that are relevant for humans (0.25–0.3%). This suppression was partially blocked in mice that were pretreated with a glucocorticoid antagonist, and administration of exogenous corticosterone also suppressed NK cell activation.

Conclusions: EtOH‐induced increases in corticosterone are apparently involved in the suppression of NK cell activation. This conclusion was supported by the lack of a direct effect of EtOH or its major metabolites (acetaldehyde and acetate) on NK cell activation by poly I:n vitro.
Japanese National Survey of Adolescent Drinking Behavior in 1996
Authors: Suzuki Kenji , Minowa Masumi , Osaki Yoneatsu
Published: May 2006

Background: Despite legal prohibition of drinking by minors, there has been no systematic attempt to monitor drinking by young Japanese. This research, the first Japanese national survey of Japanese adolescent drinking behaviors, was conducted in 1996.

Methods: In this survey, information on drinking frequency was obtained from questionnaires completed by 42,183 junior high school and 72,396 senior high school students in randomly selected schools representing all areas of Japan.

Results: Sixty percent of junior high school students and 70% of senior high school students reported having drinking experiences; 5% of junior high school students and 10% of senior high school students drank one or more times per week. Many of the junior high school students usually drank with their families and consumed small amounts, but many of senior high school students drank on various occasions and consumed larger amounts. These Japanese high school students reported being offered alcohol frequently by their parents, found it easy to buy alcoholic beverages, and believed that they had the right to determine whether to drink. Japanese adolescents' drinking has increased over the past 20 years, whereas drinking by U.S. adolescents has decreased.

Conclusions: Japanese policies aimed at decreasing adolescent drinking are inadequate. A system for monitoring and potentially modifying adolescent drinking behavior is needed.
Acute Effects of Ethanol and the First Suckling Episode in the Newborn Rat
Authors: Cheslock Sarah J. , Varlinskaya Elena I. , Silveri Marisa M. , Petrov Evgeniy S. , Spear Linda P. , Spear Norman E.
Published: May 2006

Background: In humans, early postnatal experience with alcohol is far from rare and includes exposure to alcohol through breast milk or through the bottle to attain sedative effects (Croce, 1987). Exposure to alcohol though mother's milk alters the infant's suckling behavior. However, acute effects of alcohol on suckling behavior using animal models remain to be investigated.

Methods: The present study was designed to examine the effects of neonatal alcohol exposure on attachment to a surrogate nipple and ingestion of milk in rat pups, nafve both to suckling and to maternal care. Cesarean‐delivered rat pups were pre‐exposed to four dosages of ethanol (0, 1, 2, and 3 g/kg intragastrically) and tested 30 min after ethanol administration.

Results: Suckling behavior was impaired only in pups exposed to a dosage of 3 g/kg of ethanol. Pups in this group demonstrated longer latency to attach followed by less efficient suckling–the pups maintained contact with the nipple but showed decreased ingestion of milk from it. Pups treated with 1 g/kg of ethanol showed the greatest suckling efficiency, ingesting far more milk per minute attached to the surrogate nipple than pups in all other groups. At the same time, nonevoked motor activity was significantly suppressed by all three dosages of ethanol. Blood alcohol levels showed a linear relationship with dose at 30 min postintubation.

Conclusions: These findings suggest a dissociation between acute ethanol effects on suckling and overall motor activity, with suckling apparently less sensitive to suppressive and more sensitive to activating effects of ethanol.
Occupational Stress Factors and Alcohol‐Related Behavior in Urban Transit Operators
Authors: Ragland David R. , Greiner Birgit A. , Yen Irene H. , Fisher June M.
Published: May 2006

Background: If alcohol consumption mitigates psychological and physiological aspects of the response to stressors, then alcohol consumption might be elevated for individuals exposed to high occupational stressors. Frequency of work stressors and reaction to those stressors were studied in relation to several alcohol‐related outcomes.

Methods: During the period 1993–1995, 1979 transit operators underwent medical examinations for commercial driver's license renewal. Questionnaire and interview data concerning occupational stress factors and alcohol‐related outcomes were available for 1386 (70.2%) of the operators.

Results: A positive association was found between the two job stressor‐related measures and each of six alcohol‐related outcomes. Of these 12 associations, ten were statistically significant. Individuals experiencing high self‐reported frequency of job stressors and a higher perceived severity of those job stressors were more likely to drink and more likely to be heavy drinkers. They reported more consequences of alcohol consumption, reported increased consumption since beginning work as transit drivers, and were more likely to report drinking to deal with work stress. They also drank more, but this effect was not significant for either job stress measure. There was virtually no association between either stressor‐related measure and alcohol dependency (CAGE).

Conclusions: Together with other published findings, these results suggest increased alcohol‐related outcomes in the presence of work stressors. This conclusion has potential implications for worksite health promotion and job design. Because our findings are cross‐sectional, further research is needed to clarify the causal nature of the work stressor‐alcohol association. Further research also is needed to clarify the role of individual differences and context.
A Mutation in Mitochondrial Complex I Increases Ethanol Sensitivity inCaenorhabditis elegans
Authors: Kayser Ernst‐Bernhard , Hoppel Charles L. , Morgan Phil G. , Sedensky Margaret M.
Published: May 2006

Background:The genegas‐1encodes the 49‐kDa subunit of complex I of the mitochondrial electron transport chain inCaenorhabditis elegans. A mutation ingas‐1profoundly increases sensitivity to ethanol and decreases complex I‐dependent metabolism in mitochondria.

Methods:Mitochondria were isolated from wild‐type andgas‐1strains ofC. elegans. The effects of ethanol on complex I‐, II‐, and III‐dependent oxidative phosphorylation were measured for mitochondria from each strain. Reversibility of the effects of ethanol was determined by measuring oxidative phosphorylation after removal of mitochondria from 1.5 M ethanol. The effects of ethanol on mitochondrial structure were visualized with electron microscopy.

Results:We found that ethanol inhibited complex I–, II–, and III–dependent oxidative phosphorylation in isolated wild‐type mitochondria at concentrations that immobilize intact worms. It is important to note that the inhibitory effects of ethanol on mitochondria from eitherC. elegansor rat skeletal muscle were reversible even at molar concentrations. Complex I activity was lower in mitochondria fromgas‐1animals than in mitochondria from wild‐type animals at equal ethanol concentrations. Complex II activity was higher ingas‐1than in wild‐type mitochondria at all concentrations of ethanol. No difference was seen between the strains in the sensitivity of complex III to ethanol.

Conclusions:The difference in ethanol sensitivities betweengas‐1and wild‐type nematodes results solely from altered complex I function. At the respective concentrations of ethanol that immobilize whole animals, mitochondria from each strain of worms displayed identical rates of complex I‐dependent state 3 respiration. We conclude that a threshold value of complex I activity controls the transition from mobility to immobility ofC. elegans.
Alcohol Effects on Motor Vehicle Crash Injury
Authors: Waller Patricia F. , Hill Elizabeth M. , Maio Ronald F. , Blow Frederic C.
Published: May 2006

Context: Although alcohol is frequently present in injured patients, whether it exacerbates injury and whether tolerance to alcohol changes such a relationship is less clear. Most clinical studies do not consider other important predictors of injury, making interpretation of their findings problematic.

Objective: To examine alcohol's role in injuries, taking into account other important factors, and to examine the effect of tolerance, if any.

Design: Prospective cohort study.

Setting: University hospital and community hospital emergency departments and morgue.

Patients: 1362 Motor Vehicle Crash patients age ≥18, treated and released, admitted, and deceased.

Main Outcome Measures: Excess injury measured by Injury Severity Scale (ISS) 90, Weighted Revised Trauma Score (WRTS), and G‐Score.

Results: Using regression analysis, the best predictors of injury severity were vehicle crush (TAD), safety belt use, and their interaction, and age. Alcohol use further predicted injury. Using the final regression model, the effect of alcohol was to increase ISS90, on average, by about 30% (from a predicted ISS90 of 5.1 to 6.8, all else being equal). The adjusted odds ratio for serious injury (ISS90>15), was 1.59 for a patient with a positive blood alcohol concentration (alc+) compared to a alc− patient. This potentiating effect is seen even for patients with low levels of alcohol (<22mmol/liter; <0.100 BAC) but is not linear with increasing alcohol level. Tolerance to alcohol did not affect the potentiation of injury by alcohol.

Conclusion: When other relevant variables are considered, alcohol increases injury, but the effects of alcohol level and alcohol tolerance are less clear. These findings have important implications for injury prevention, treatment, and research.
Risk Criteria for Nuclear Power Plants: A Pragmatic Proposal1
Authors: Starr Chauncey
Published: May 2006

Criteria are proposed for both an acceptable upper bound of nuclear power plant risk and a lower bound as a design target. Recognizing that the public risk associated with a power plant can be estimated only by probabilistic analysis of the design features, the spread between the lower design target and the upper bound provides a margin for uncertainty in th probabilistic estimate. The combination of a low probabilistic design target and this margin provides a reasonable expectation that the overall performance will be in the domain of an acceptable risk level. Because the exposure to potential risk is chiefly in the locality of the nuclear station, it is also proposed that compensatory benefits should be provided locally and that these be included as a cost of operation. It is suggested that the upper bound be set at a risk level equivalent to those risks of routine living which are normally accepted, i.e., about 10‐4 deaths per year per person (100 deaths/yr/million). The proposed lower design target is 10‐8 (0.1 deaths/yr/million), about one‐hundredth of the minimal risk from the natural hazards all people are exposed to.
Assessment for Catastrophic Risks
Authors: Fairley William B.
Published: May 2006

Records of nonoccurrence of catastrophic accidents from technologically based industrial operations, such as nuclear power generation and liquefied natural gas (LNG) transportation are sometimes cited as evidence of the safety of such operations. The appropriateness and inappropriateness of different types of models of accident processes for these systems are discussed. Selectivity biases in defining both die numerator and denominator for accident rates are shown to be important to the size of the estimated rate and these are illustrated by examples. Inferential approaches to estimating a rate based on zero occurrences are briefly discussed. The conclusion reached is that a record of zero occurrences is of cold comfort in ruling out catastrophic events. Experience, unless it is interpreted by strong models and assumptions, helps little to establish very small probabilities of a catastrophe.
Risk Analysis, Philosophy, and the Social and Behavioral Sciences: Reflections on the Scope of Risk Analysis Research
Authors: Covello Vincent T. , Menkes Joshua , Nehnevajsa Jiri
Published: May 2006

This paper reviews the contributions of philosophy and the social and behavioral sciences to risk analysis. It concludes that philosophical, social, and behavioral research can contribute to the resolution of complex risk issues in at least four areas: (i) comparative risk analysis; (ii) the use of risk‐related scientific information in the decision‐making process; (iii) risk perception; and (iv) institutional and organizational features of the risk‐management system.
Risk and Consent: Philosophical Issues for Centralized Decisions
Authors: MacLean Douglas
Published: May 2006

Centralized decisions that impose risks demand a justification. The most promising way to justify these decisions is in terms of consent of those people who will be affected by them. Attempts to determine how safe is safe enough in terms of justice, rights, or efficiency are unlikely to get us very far. The problem with consent, however, is that actual consent is impossible to obtain for decisions that affect large numbers of persons. For this reason, we need to explore other kinds of consent and the idea of what a reasonable person would agree to. Three models of consent are described, each one more powerful (but more controversial) in terms of its potential for justifying centralized decisions.
Why Study Risk Perception?
Authors: Slovic Paul , Fischhoff Baruch , Lichtenstein Sarah
Published: May 2006

Studies of risk perception examine the opinions people express when they are asked, in various ways, to characterize and evaluate hazardous activities and technologies. This research aims to aid risk analysis and societal decision making by (i) improving methods for eliciting opinions about risk, (ii) providing a basis for understanding and anticipating public responses to hazards, and (iii) improving the communication of risk information among laypeople, technical experts, and policy makers.
The Theory of Risk Homeostasis: Implications for Safety and Health
Authors: Wilde Gerald J. S.
Published: May 2006

No strategy for countermeasure design or future directions of research in the areas of human behavior which leads to traffic accidents or lifestyle‐related diseases can be rationally developed without an acceptable working theory of human behavior in these domains. For this purpose, an attempt has been made to conceptually integrate the available evidence with respect to the role of human behavior in the causation of road accidents. From this integrative effort it would seem that the accident rate is ultimately dependent on one factor only, the target level of risk in the population concerned which acts as the reference variable in a homeostatic process relating accident rate to human motivation. Various policy tactics for the purpose of modifying this target level of risk have been pointed out and the theory of risk homeostasis has been speculatively extended to the areas of lifestyle‐dependent morbidity and mortality.
Technical Uncertainty in Quantitative Policy Analysis — A Sulfur Air Pollution Example
Authors: Morgan M. Granger , Morris Samuel C. , Henrion Max , Amaral Deborah A. L. , Rish William R.
Published: May 2006

Expert judgments expressed as subjective probability distributions provide an appropriate means of incorporating technical uncertainty in some quantitative policy studies. Judgments and distributions obtained from several experts allow one to explore the extent to which the conclusions reached in such a study depend on which expert one talks to. For the case of sulfur air pollution from coal‐fired power plants, estimates of sulfur mass balance as a function of plume flight time are shown to vary little across the range of opinions of leading atmospheric scientists while estimates of possible health impacts are shown to vary widely across the range of opinions of leading scientists in air pollution health effects.
Variability of Site‐Reactor Risk
Authors: Margulies Timothy S. , Blond Roger M.
Published: May 2006

Reactor accident consequence models have been developed (for example, the CRAC model of the Reactor Safety Study (RSS), WASH‐1400) to predict the offsite health and economic consequences of severe accidents at a reactor site with generic demographic and meteorological characteristics. Application of a revised RSS accident consequence model, CRAC2, to 91 existing sites results in a band of risk curves around the earlier WASH‐1400 average reactor/site predictions. This paper examines these calculations and important model assumptions such as population distribution, emergency response, and meteorological data with respect to their effects on site risk extremes—that is, the combination of high consequence/low probability events.
Risk Assessment for Interconnected Electrical Power Grids
Authors: Hauptmanns Ulrich
Published: May 2006

Using an analogy with costs, risk is split into a fixed and a variable contribution. Based on this concept, the total risk of an interconnected electrical power grid is minimized. The theoretical foundations of the method are explained and illustrated by model calculations.
A Review of Plant Specific PRAs
Authors: Joksimovich V.
Published: May 2006

A large number of PRA studies have been completed for specific plants at specific sites. From these studies, taken individually or collectively, many significant insights have evolved into items important to risk and safety. The content of this paper is primarily based on the material contained in the EPRI funded review of five PRA studies: Big Rock Point, Zion, Limerick, Grand Gulf, and Arkansas Nuclear One. The first three were the utility sponsored studies publicly available at the time of project initiation while the other two were deemed representative of the NRC's RSSMAP and IREP programs respectively. The results of PRA studies are usually expressed in terms of core melt frequencies, radionuclide release frequencies, and frequencies of occurrence of different reactor accident consequences (e.g., early and latent fatalities) depending on the level of PRA. These subjects are prominently addressed in this paper. One of the results of a PRA study is identification of a relatively small number of accident sequences that represent the dominant contributors to core melt. An analysis of the salient features of the dominant accident sequences from eleven PRA's yielded a characterization of accident sequence categories discussed at some length. Impact of external events is discussed very briefly. Next to an explicit quantification of public risk or core melt frequency, the identification of specific safety concerns and the evaluation of possible solutions to implement risk management are probably the best recognized and most widely used applications of PRA. Several illustrative examples are briefly discussed. Human interactions are extremely important contributors to safety and reliability of the plants. A review of PRA studies concluded that it was necessary to account for five types of human interactions; some of which may mitigate while others may exacerbate an accident sequence.
A Nuclear Utility's Views on the Use of Probabilistic Risk Assessment
Authors: Daniels Thomas A. , Canady K. S.
Published: May 2006

Probabilistic risk assessment (PRA) is a relatively new tool in the nuclear industry. The Reactor Safety Study started the present trend of conducting PRAs for nuclear power plants when it was published in 1975. Now, nine years later, those in the industry currently using PRA techniques are frequently asked the same question: Why should the nuclear utility industry, with so many accepted analytical tools already available, invest the time and manpower to develop a new technique with so many uncertainties?
The Management of Risk: Application to the Welding Industry
Authors: Stern Richard M.
Published: May 2006

The management of health risk in the welding industry is considered based on a discussion of the major sources of harm to welders arising from their employment (e.g., accidents and inhalation of fumes and gases). It is shown that present methods neither enable the assessment of the societal and human costs involved, nor permit the specific association of delayed health effects to occupational fume exposures. Reported accidents usually occur early in the working experience and contribute to a large number of working days lost, while fume exposures may contribute to a reduction in life quality which is poorly defined. It is concluded that risk management can only be attempted after much more information is made available concerning the origin, nature, and duration of health effects, especially as related to individual welding technologies and applications.

SUMMARY AND CONCLUSIONS

The reduction of risk in the welding industry requires the development of an approach to risk management. Although it is difficult to demonstrate that welders on the average suffer excess risk when compared to similar skilled manual occupations, there is some evidence of possible high risk associated with certain welding operations: currently available information is extremely limited.

It is extremely difficult to rank various types of potential risk. On the other hand it is possible to try to identify certain situations, individuals, combinations of circumstances which lead to excess occupational health risk.

A complete picture of the risk infrastructure can be obtained by a proper survey of each enterprise. Steps can immediately be taken for the elimination of unnecessary risk, especially from accidents. The problems with respect to delayed health effects, especially cancer, are less tractable. In particular much effort must be placed in the strategies for the management of small excess risks of delayed health effects and large variations in inter‐individual risk susceptibilities.
Risk Analysis and Risk Management: An Historical Perspective
Authors: Covello Vincent T. , Mumpower Jeryl
Published: May 2006

This paper reviews the history of risk analysis and risk management, giving special emphasis to the neglected period prior to the 20th century. The overall objective of the paper is to: (1) dampen the prevailing tendency to view present‐day concerns about risk in an ahistorical context; (2) shed light on the intellectual antecedents of current thinking about risk; (3) clarify how contemporary ideas about risk analysis and societal risk management differ significantly from the past; and (4) provide a basis for anticipating future directions in risk analysis and management.
Warning Systems and Defense Policy: A Reliability Model for the Command and Control of U.S. Nuclear Forces
Authors: Paté‐Cornell M. E. , Neu J. E.
Published: May 2006

The U.S. Command, Control, Communication and Intelligence System (C3I) includes sensors (e.g., satellites and radars), communication links, and computer systems that allow gathering and processing of information that a missile attack on the continental United States may be on the way. The choice of a policy of response to such an attack depends in part on the reliability of the information coming from the C3I. We consider in this study four possible response policies: (1) launch on impact, (2) launch on attack assessment, (3) launch under attack, and (4) launch on warning. We propose a method to compute, for each policy, the probability of accidental nuclear strike and the probability of being unable to respond due to a malfunction of the C3I or to partial destruction of the response forces. We include in our system the launch authorization steps (permissive action links) and a very crude analysis of the survivability of second strike forces. We examine the variations of probabilities of Type I and Type II errors and the tradeoffs involved when shifting from a policy of launch on impact to another launch policy. We conclude that this simple but powerful method allows one to gain a good grasp on some of the complex issues involved.
An Evaluation of Alternative Safety Criteria for Nuclear Power Plants
Authors: Solomon Kenneth A. , Nelson Pamela F. , Chiesa James R. , Wolf Katy
Published: May 2006

Safety criteria for frequency of nuclear‐reactor accidents and for reactor‐induced risk to individuals and to society are evaluated on the basis of their comprehensiveness, clarity, recognition of uncertainty, practicability, defensibility, simplicity, and internal consistency. Many criteria were found to be comprehensive and practicable; few completely satisfied the other evaluation standards. A consensus inferred from the most favorably evaluated criteria would allow between 1.0time10‐4 and 1.0time10‐3 core melts per reactor year, between 1.0time10‐6 and 2.0time10‐5 fatalities per reactor year per individual, and a total exposure in the United States of between 1000 and 10,000 person rems per reactor year. This consensus is consistent with the criteria proposed in NUREG0880.
Analytic Bayesian Solution of the Two‐Stage Poisson‐Type Problem in Probabilistic Risk Analysis
Authors: Fröhner F. H.
Published: May 2006

The basic purpose of probabilistic risk analysis is to make inferences about the probabilities of various postulated events, with an account of all relevant information such as prior knowledge and operating experience with the specific system under study, as well as experience with other similar systems. Estimation of the failure rate of a Poisson‐type system leads to an especially simple Bayesian solution in closed form if the prior probability implied by the invariance properties of the problem is properly taken into account. This basic simplicity persists if a more realistic prior, representing order of magnitude knowledge of the rate parameter, is employed instead. Moreover, the more realistic prior allows direct incorporation of experience gained from other similar systems, without need to postulate a statistical model for an underlying ensemble. The analytic formalism is applied to actual nuclear reactor data.
Discrete Probability Distributions for Probabilistic Fracture Mechanics
Authors: Kurth Robert E. , Cox David C.
Published: May 2006

Recently, discrete probability distributions (DPDs) have been suggested for use in risk analysis calculations to simplify the numerical computations which must be performed to determine failure probabilities. Specifically, DPDs have been developed to investigate probabilistic functions, that is, functions whose exact form is uncertain. The analysis of defect growth in materials by probabilistic fracture mechanics (PFM) models provides an example in which probabilistic functions play an important role. This paper compares and contrasts Monte Carlo simulation and DPDs as tools for calculating material failure due to fatigue crack growth. For the problem studied, the DPD method takes approximately one third the computation time of the Monte Carlo approach for comparable accuracy. It is concluded that the DPD method has considerable promise in low‐failure‐probability calculations of importance in risk assessment. In contrast to Monte Carlo, the computation time for the DPD approach is relatively insensitive to the magnitude of the probability being estimated.
Notes on the Interpretation of Traffic Accident Data and of Risk Homeostasis Theory: A Reply to L. Evans
Authors: Wilde Gerald J. S.
Published: May 2006

A quick and summary comment is made on a paper by Evans,(1) who set out to “definitively answer” the question “whether there is any validity” in risk homeostasis theory (RHT), and who arrives at the conclusion that the “theory should be rejected” because the data “provide the clearest evidence refuting the theory.” It will be argued here that the seven cases Evans puts forward against RHT do not justify such a rather boldly‐worded conclusion. On the contrary, the data presented by Evans can be seen to be either not inconsistent with RHT (Case 1), in error (Case 2), or fail to take account of relevant economic changes (Case 3) and of pertinent exposure variables (Case 5), incomplete or the product of guesswork (Case 4), irrelevant (Case 6), nonrepresentative (Case 7) and in all cases open to alternative interpretations that do not conflict with the theory under debate. Moreover, Evans’reasoning seems to betray not only careless reading of what RHT does in fact say, but also a fundamental misunderstanding of the notion of target risk in particular. Refuting a “refutation” does not, of course, imply that RHT is valid, or valid at least within as yet to be defined limits. Attempts to address the validity question should preferably take the form of well‐controlled field experiments, instead of retrospective analyses of multünterpretable archival data that can be debated ad infinitum.
Health Risks of PCB Spills from Electrical Equipment
Authors: Eschenroeder Alan Q. , Doyle Colleen P. , Faeder Edward J.
Published: May 2006

The Southern California Edison Company (SCE) has instituted a series of control strategies designed to minimize human exposure to polychlorinated biphenyls (PCBs) in electrical equipment used on its system. This paper describes a method of analyzing PCB risks using conservative estimates of human intake of PCBs originating from accidental spills from electrical equipment. The PCB releases from the Edison system were determined. The fate of these releases in soil, air, and water was analyzed to determine how much material reaches human receptors. The air and water pathways were determined to be the most likely candidates for the exposure and risk considerations. PCB intake via ingestion of soil at the spill site was neglected as an exposure pathway. Equipment spills without controls resulted in at the most 2 ng/day human intake of PCBs via the water exposure pathway. This was determined to be negligible in comparison with intake rates used in conjunction with the setting of food tolerance levels based on fish being the main dietary pathway of human exposure. The inhalation exposure of the hundred or so persons in the immediate vicinity of a spill was determined to equal the PCB intakes of the fish‐eating subpopulation analyzed by the Food and Drug Administration for 2 ppm tolerance standard in the case of no controls or cleanup. Current cleanup procedures assure that even the persons in the immediate area are well below the intake of the subjects in the fish contamination analysis. All exposures were well below a “virtual safe dose” level estimated in the fish tolerance study.
Chemical Spill Exposure Assessment
Authors: Brown Stuart M. , Silvers Abraham
Published: May 2006

POSSM, the PCB On‐Site Spill Model, is a contaminant transport model developed to predict environmental concentrations associated with a chemical spill. The model predicts daily changes in chemical concentrations on a spill site (e.g., in soil and on vegetation) and losses of chemical due to volatilization, surface runoff/soil erosion, and leaching to groundwater. Spill areas consisting of soil/vegetation and/or an impervious surface (e.g., asphalt and concrete) can be analyzed, as can different spill cleanup practices. POSSM is used to analyze exposure levels associated with a hypothetical capacitor spill. While the model was developed for PCB spills, it is generally applicable to a number of organic compounds.
Managing Technological and Environmental Risks in Japan
Authors: Ikeda Saburo
Published: May 2006

This paper is primarily concerned with environmental risks arising from utilizing modern technology. Our attention focuses on the interface between policy decisions and regulatory measures. The interface involves not only science and technology but also politics and social values, and perceptions which are deeply rooted in the industrial countries. A case of setting air quality standards and regulatory practices in Japan is studied on the basis of scientific and technological knowledge, economic cost, and subjective judgment of what constitutes an acceptable level of risk or health hazard.
Comparative Fire Risk Study of PCB Transformers
Authors: Boykin Raymond F. , Kazarians Mardyros , Freeman Raymond A.
Published: May 2006

A risk assessment comparing the acute effects of mineral oil and PCB‐askarel dielectric fluids in two transformer sites was performed. The first site has the installation characteristics for a PCB‐askarel‐filled transformer with sprinkler fire protection. A risk comparison is made between two types of transformers (PCB‐askarel‐filled and mineral oil‐filled) for this site. The second site (a vault) has the installation characteristics for a mineral oil‐filled transformer, and a risk comparison is made in a fashion similar to the first site. Risk is expressed in terms of frequencies of one or more acute injuries or fatalities per transformer year.
Using Average Lifetime Dose Rate for Intermittent Exposures to Carcinogens
Authors: Kodell Ralph L. , Gaylor David W. , Chen James J.
Published: May 2006

The effect of using the average dose rate over a lifetime as a representative measure of exposure to carcinogens is investigated by comparing the true theoretical multistage intermittent‐dosing lifetime low‐dose excess risk to the theoretical multistage continuous‐dosing lifetime risk corresponding to the average lifetime dose rate. It is concluded that low‐dose risk estimates based on the average lifetime dose rate may overestimate the true risk by several orders of magnitude, but that they never underestimate the true risk by more than a factor of k/r, where k is the total number of stages in the multistage model and r is the number of stages that are dose‐related.
Infant Exposure Assessment for Breast Milk Dioxins and Furans Derived from Waste Incineration Emissions
Authors: Smith Allan H.
Published: May 2006

Polychlorinated dibenzo‐p‐dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) have been detected in human milk samples obtained in several countries. Possible sources include emissions from incineration of municipal waste in resource recovery facilities. A formula is presented for calculating the infant daily dose of dioxin equivalents from breast milk on the basis of the maternal daily intake. Application of the formula suggests that an infant breast‐fed for 12 months would receive around 10% of the cumulative exposure dose per body weight that would be received by an adult with 50 years of exposure. Further analysis indicated that the contribution of dioxin equivalents from breast milk to an infant's body concentration at the end of 12 months of breast feeding would amount to 1.7 times the concentration in the mother. However, dioxin and furan emissions from a source calculated to result in worst‐case lifetime cancer risks of the order of 1 in 100,000 are only likely to increase breast milk concentrations by around 1%–10% of the levels that have been detected in several countries. This finding suggests that there are major sources of dioxins and furans other than from municipal solid waste incineration that need to be identified.
On Weighing Gains and Investments at the Margin of Risk Regulation
Authors: O'Riordan Timothy , Kemp Ray , Purdue H. Michael
Published: May 2006

Analysts have long noted an apparent discrepancy in the level of investment seemingly necessary to meet “acceptable” levels of public safety. At the margin of risk regulation, i.e., where safety determination is judged acceptable, the traditional cost–benefit calculus appears to contribute obvious rationale to the final political decision. Efforts are now being made to introduce a measure of consistency into the application of risk–cost benefit analysis to radiological protection. This paper reviews these efforts from a UK perspective. It also looks at how the issue was treated in a public setting through the Sizewell B Public Inquiry.