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971.
Risk-based cleanup goals or preliminary remediation goals (PRGs) are established at hazardous waste sites when contaminant concentrations in air, soil, surface water, or groundwater exceed specified acceptable risk levels. When derived in accordance with the Environmental Protection Agency's risk assessment guidance, the PRG is intended to represent the average contaminant concentration within an exposure unit area that is left on the site following remediation. The PRG, however, frequently has been used inconsistently at Superfund sites with a number of remediation decisions using the PRG as a not-to-exceed concentration (NTEC). Such misapplications could result in overly conservative and unnecessarily costly remedial actions. The PRG should be applied in remedial actions in the same manner in which it was generated. Statistical methods, such as Bower's Confidence Response Goal, and mathematical methods such as "iterative removal of hot spots," are available to assist in the development of NTECs that ensure the average postremediation contaminant concentration is at or below the PRG. These NTECs can provide the risk manager with a more practical cleanup goal. In addition, an acute PRG can be developed to ensure that contaminant concentrations left on-site following remediation are not so high as to pose an acute or short-term health risk if excessive exposure to small areas of the site should occur. A case study demonstrates cost savings of five to ten times associated with the more scientifically sound use of the PRG as a postremediation site average, and development of a separate NTEC and acute PRG based on the methods referenced in this article. 相似文献
972.
David C. Bellinger 《Risk analysis》2003,23(1):163-174
Three topics are addressed: (1) measurement issues (e.g., the reliability and validity of neurobehavioral test scores), (2) general principles of assessment, including test selection, and (3) interpretation of scores. Psychological tests generally perform as well as medical tests in terms of reliability and validity. Test manuals, assessment textbooks, and psychologists are useful resources to the risk assessor. The variety of different tests employed in neurobehavioral studies complicates interstudy comparisons. In addition, tests that ostensibly assess the same general domain of function might assess somewhat different abilities within that domain. Although a uniform battery for use in all studies seems desirable, the battery appropriate for a specific study depends on study goals, knowledge about the mechanism(s) of neurotoxicity, nature of the study population, and pattern of exposure. Exposure-related neurobehavioral deficits are generally indicators of "altered function" rather than of "clinical disease." Limiting concern to end points corresponding to clinical disease might not be appropriate. Many neurobehavioral diagnoses are phenomenological and a neurotoxicant might cause a unique pattern of deficits for which no label has been created. The concern that a small shift in the central tendency of a distribution of test scores has no significance for the individual should be reexamined in light of the prevention paradox, formulated on the basis of epidemiologic studies of chronic disease. Poor performance on a neurobehavioral test does not necessarily map clearly onto underlying behavioral or neural substrate. The absence of such linkages, given current knowledge about brain-behavior relationships, should not reduce confidence in neurobehavioral end points. Use of neurobehavioral test scores involves considerations that differ little from those that the risk assessor routinely addresses in using end points commonly used in research on other topics in environmental epidemiology. 相似文献
973.
Risk perceptions have, to a great extent, been studied exclusively as individual cognitive mechanisms in which individuals collect, process, and form perceptions as atomized units unconnected to a social system. These individual-level theories do not, however, help explain how perception of risk may vary between communities or within a single community. One alternative approach is based on a network theory of contagion. This approach, emerging largely from organizational and community social network studies, suggests that it is the relational aspects of individuals and the resulting networks and self-organizing systems that influence individual perceptions and build "groups or communities of like-minded" individuals. These social units, it is argued, behave as attitude, knowledge, or behavioral structures. The study reported in this article tests one aspect of this theoretical perspective. The central hypothesis proposes the existence of risk perception networks--relational groupings of individuals who share, and perhaps create, similar risk perceptions. To test this idea, data were collected from individuals involved in a community environmental conflict over a hazardous waste site cleanup. The statistical analysis used a matrix of relational social linkages to compare with a matrix of individual risk perceptions The analysis confirmed the hypothesis suggesting that social linkages in communities may play an important role in focusing risk perceptions. 相似文献
974.
975.
Corrigan P Markowitz FE Watson A Rowan D Kubiak MA 《Journal of health and social behavior》2003,44(2):162-179
In this study, we build on previous work by developing and estimating a model of the relationships between causal attributions (e.g., controllability, responsibility), familiarity with mental illness, dangerousness, emotional responses (e.g., pity, anger, fear), and helping and rejecting responses. Using survey data containing responses to hypothetical vignettes, we examine these relationships in a sample of 518 community college students. Consistent with attribution theory, causal attributions affect beliefs about persons' responsibility for causing their condition, beliefs which in turn lead to affective reactions, resulting in rejecting responses such as avoidance, coercion, segregation, and withholding help. However, consistent with a danger appraisal hypothesis, the effects of perceptions of dangerousness on helping and rejecting responses are unmediated by responsibility beliefs. Much of the dangerousness effects operate by increasing fear, a particularly strong predictor of support for coercive treatment. The results from this study also suggest that familiarity with mental illness reduces discriminatory responses. 相似文献
976.
Ellickson PL Bird CE Orlando M Klein DJ McCaffrey DF 《Journal of health and social behavior》2003,44(4):525-535
This paper examines the links between individual adolescent smoking behavior and actual and perceived smoking behavior in the individual's school cohort. We hypothesized that students enrolled in schools with higher smoking prevalence among students in their grade are more likely to smoke subsequently. We also expected perceived school-level prevalence of smoking to have a greater impact than actual prevalence because the former is a more direct measure of perceived norms. Adjusting for demographics, actual school-level prevalence at baseline (grade 7) was strongly associated with smoking frequency one year later. However, the association disappeared after adjusting for individual smoking frequency at baseline. School-level prevalence did not moderate the association between individual's baseline and subsequent smoking frequency. Perceived prevalence of smoking among grade 8 students and two measures tapping the behavior of smaller peer groups--cigarette offers and exposure to friends and other peers who smoke--were associated with increased risk of smoking. 相似文献
977.
978.
Intermarriage and the demography of secularization 总被引:1,自引:0,他引:1
Voas D 《The British journal of sociology》2003,54(1):83-108
One way of measuring religious affiliation is to look at rites of initiation such as baptism. English statistics show that for the first time since the Church of England was founded, less than half the nation is Anglican on this criterion. The pattern of formal religious transmission changed during the Second World War. Previously christening was quasi-universal, and the Church of England was the preferred provider. By the end of the war baptism was evidently optional, and chosen principally by parents whose religious identities matched. Further analysis suggests that affiliation now tends to be lost following marriage to someone from a different religious background, though the USA differs from Europe in this respect. A demographic theory of advanced secularization is outlined that specifies a proximal cause for declining religious affiliation, and provides tools for predicting the changes to be expected over future decades. The theory also helps to explain why affiliation may fall most quickly where there is most religious diversity. 相似文献
979.
Best practice in couple relationship education 总被引:1,自引:1,他引:0
Relationship education is widely available to couples and is intended to reduce the prevalence of relationship distress, divorce, and the associated personal and social costs. To realize the potential benefits of couple relationship education, it needs to be evidence-based, offered in ways that attract couples at high-risk for relationship problems, and focused on factors that put couples at high-risk for future relationship problems. 相似文献
980.
Overviews evidence-based family treatments for adolescent conduct problems. Three treatments succeed in meeting recommendations for treatment development set forth in recent evaluations by reviewers and federal entities. These treatments (Functional Family Therapy, Multisystemic Therapy, and Oregon Treatment Foster Care) have achieved their success by using the science base of known risk factors, providing an effective alternative to restrictive placements, and using scientific methods to evaluate effectiveness. Major features of these three treatments are presented, including clinical and quality assurance procedures, controlled outcome research support, cost analyses, and process research. Bases of treatment success and parallels among the three approaches are summarized, as is their transport and dissemination to practice settings. Finally, suggestions for future research and clinical implications are discussed. 相似文献