Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Risk Assessment”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2Linked to original sources

A probabilistic framework for non-cancer risk assessment.

Risk assessment involves an analysis of the relationship between exposure and health related outcomes to derive an allowable exposure level or to estimate a low-dose risk. Acceptable levels of human exposure for non-cancer effects generally are derived by dividing an experimental no-observed-adverse-effect-level or a lower confidence limit benchmark dose by a product of several uncertainty factors. This paper presents a hierarchical modeling framework for a probabilistic approach to non-cancer risk assessment. The hierarchical model integrates the distributions of uncertainty factors and the distribution of the actual exposure level to construct the dose-response model for the proportion of population at risk and the dose-response model for the expected proportion of population at risk for a given exposure distribution. The proposed approach is based on the use of the BMDL (lower confidence limit on the benchmark dose) as a POD (point of departure) for risk assessment of non-cancer effects.

Animals↗

A conceptual framework to assess the risks of human disease following exposure to pathogens. ILSI Risk Science Institute Pathogen Risk Assessment Working Group.

Currently, risk assessments of the potential human health effects associated with exposure to pathogens are utilizing the conceptual framework that was developed to assess risks associated with chemical exposures. However, the applicability of the chemical framework is problematic due to many issues that are unique to assessing risks associated with pathogens. These include, but are not limited to, an assessment of pathogen/host interactions, consideration of secondary spread, consideration of short- and long-term immunity, and an assessment of conditions that allow the microorganism to propagate. To address this concern, a working group was convened to develop a conceptual framework to assess the risks of human disease associated with exposure to pathogenic microorganisms. The framework that was developed consists of three phases: problem formulation, analysis (which includes characterization of exposure and human health effects), and risk characterization. The framework emphasizes the dynamic and iterative nature of the risk assessment process, and allows wide latitude for planning and conducting risk assessments in diverse situations, each based on the common principles discussed in the framework.

Disease↗

Perceived risk, real risk: social science and the art of probabilistic risk assessment.

Risk assessment is commonly seen as the domain of physical and biological sciences, with social scientists focusing instead on risk management and communication. This division is unnecessary, and it may lead to errors in risk assessments. Social science input is needed for more accurate calculations of risk consequences and probabilities and for identifying potential biases created by certain risk assessment procedures, as well as in analyzing and explaining public responses to risk. Findings, moreover, suggest that the dichotomy between "real" and "perceived" risk is less "real" than is often assumed, particularly in cases involving controversial technologies.

Accidents↗

Mechanistic modelling and risk assessment.

Risk Assessment in the United States has been rapidly changing over the last few years. The historical methods and endpoints by which risk estimates were derived are gradually being replaced by newer methods and a broader spectrum of endpoints. For carcinogenic risk assessment, there is movement from the routinely used "linearized multistage model" for low dose risk estimation to methodology which is more deeply rooted in carcinogenic mechanisms and which allows the incorporation of additional data into the estimation of risks in a direct, quantitative fashion. There is also a determined effort under way to develop methods for assessing risks from exposure based on other endpoints such as effects on the immune system and the reproductive system. This paper briefly discusses some of the statistical and mathematical issues which will play important roles in determining the utility and precision of these new methods for estimating risks from environmental exposures.

Animals↗

[Risk assessment and risk prevention in infectious diseases].

The purpose of risk assessment is to provide source data to state and local health agencies and other administrative departments to aid in the development of approaches for risk management and preventive strategies. In respect of the far reaching consequences it is necessary to have evaluated and accepted measures for the risk assessment. The system of risk assessment was developed in the USA for the assessment of chemical substances and includes the identification of the hazard, the exposure assessment, the dose-response-assessment and the risk assessment. Basis for the risk assessment are detailed information of the chemical substance or the pathogen and epidemiologic data. Preventive strategies and risk management like the stop of production have great social and economic consequences. Risk management must be highly effective. In a historic review it is described that in the past of the former centuries infectious diseases were tried to prevent or control in a wrong manner in consequence of the lack of knowledge about the etiology of infectious diseases. Since Robert Koch there was the beginning of an effective risk assessment and management of infectious diseases. Long time in this century it was thought that infectious diseases wouldn't play any role for the public health. Now it is clear that infectious diseases remain the leading cause of death and disability in the developed and underdeveloped countries and that the risk potential is increasing. Therefore risk-assessment and risk-management developed formerly for chemical substances are necessary for infectious diseases. Specific criteria for-the risk assessment for infectious diseases which are different to chemical substances are discussed like illness related, pathogen related, host related, transmission related factors and general aspects. The most important measures for risk management are discussed.

Communicable Disease Control↗

[Biological monitoring and risk assessment].

Risk assessment in occupational medicine is the part of risk analysis where physicians also contribute. A risk is the probability of an adverse health effect and derives from the hazard posed by a given chemical and from exposure characteristics. Due to the complexity of this process, models are used in occupational medicine, where risk factors are identified and exposure estimated, combined with an understanding of the severity of possible effects. Theoretically, the advantages of biological monitoring are obvious. However, the paucity of available data on biological monitoring limits its uses. Moreover, the utilization of data on biological monitoring requires evaluation of their significance. Examples are discussed to highlight advantages and limitations of biological monitoring data in both hazard and risk assessments. They include exposure to polycyclic aromatic hydrocarbons, benzene, other carcinogens, paraquat and polychlorinated biphenyls.

Benzene↗

Public participation in life cycle assessment and risk assessment: a shared need.

Life cycle assessment (LCA) and risk assessment are operationally different but share the common purpose of supporting decisions about reducing threats to human welfare. Both analysis methods also involve a complex mixture of science and value judgments reflecting epistemological as well as moral and esthetic values. The inability of risk assessment and LCA to be "value free" has been a source of considerable controversy in both communities. Recognition of the contingent and social nature of human interpretation of the risks and environmental impacts created by public and private decisions has led to an increased appreciation of the importance of involving interested and affected parties in risk characterization. Comparison of the value-based nature of LCA and risk assessment demonstrates the need for participation in LCA. Although the need for participation by affected parties in decision-making processes is gaining acceptance, there is little agreement as to how participation should be structured. Risk assessment and LCA have a shared need for research examining the design and analysis of participation processes appropriate to a given decision context. A proposed framework recommends participation strategies designed to enhance the effectiveness of policy-driven analyses such as risk assessment and LCA based on the level of trust that interested and affected parties have for other policy participants.

Decision Making↗

A public health context for residual risk assessment and risk management under the clean air act.

The 1990 amendments to the Clean Air Act required the EPA to institute new pollution control technology requirements for industrial sources of air pollution. In part because agreement could not be reached on the best way for the EPA to determine whether any significant risks to human health will remain after the technology controls are in place, the amendments also created a Commission on Risk Assessment and Risk Management and gave the commission a broad mandate to review and make recommendations concerning risk assessment and risk management in federal regulatory programs. In its March 1997 final report to Congress and the administration, the commission recommended a tiered approach to assessing such residual risks. That approach included the idea that when decisions about managing residual risks are made, emissions should be evaluated in the context of other sources of air pollution. Evaluating risks in their larger contexts is consistent with what the commission called a public health approach to environmental risk management. This paper describes the public health approach and how it applies to evaluating residual risks under the Clean Air Act.

Air Pollution↗

Accounting for inherent variability of growth in microbial risk assessment.

Risk assessments of pathogens need to account for the growth of small number of cells under varying conditions. In order to determine the possible risks that occur when there are small numbers of cells, stochastic models of growth are needed that would capture the distribution of the number of cells over replicate trials of the same scenario or environmental conditions. This paper provides a simple stochastic growth model, accounting only for inherent cell-growth variability, assuming constant growth kinetic parameters, for an initial, small, numbers of cells assumed to be transforming from a stationary to an exponential phase. Two, basic, microbial sets of assumptions are considered: serial, where it is assume that cells transform through a lag phase before entering the exponential phase of growth; and parallel, where it is assumed that lag and exponential phases develop in parallel. The model is based on, first determining the distribution of the time when growth commences, and then modelling the conditional distribution of the number of cells. For the latter distribution, it is found that a Weibull distribution provides a simple approximation to the conditional distribution of the relative growth, so that the model developed in this paper can be easily implemented in risk assessments using commercial software packages.

Bacteria↗

Assessing the risk assessment paradigm.

Risk assessment provides an essential framework for organizing, evaluating and characterizing scientific information on the nature and magnitude of hazards from specific chemicals. Such characterization of risk is needed for risk communication and for risk reduction and management. Each element of the risk assessment paradigm--hazard identification, dose-response, exposure analysis and risk characterization--is the target of important efforts to improve methodologies and the biological plausibility and clinical significance of our conclusions.

Animals↗

Necessity to establish new risk assessment and risk communication for human fetal exposure to multiple endocrine disruptors in Japan.

Our recent study clearly shows that fetuses are exposed to multiple chemicals including endocrine disruptors in Japan. Although the embryo and fetus stages are the most sensitive period to chemicals in humans' life cycle, the health effects of the chemicals such as endocrine disruptors to them are largely unknown. The conventional risk assessment method cannot assess the risk to fetuses precisely. Now we need a new risk assessment, in which the target is fetuses and not the adults, in addition to the conventional risk assessment. At the same time, we also need a new strategy to practically eliminate the risk for the future generations. To make the strategy effective, we suggest a new approach to reduce the risk and avoid the possible adverse health effects, using primary, secondary and tertiary preventions as they are used in public health. We also suggest a new concept of "pre-primary prevention" to reduce the risk for fetuses. Furthermore, to make this method even more practical, we suggest a new risk communication method. In this paper, we present a framework of risk avoidance of multiple chemical exposure to fetuses.

Congenital Abnormalities↗

Stakeholder position paper: the need for antimicrobial use data for risk assessment.

Risk assessment seeks to estimate the probability and impact of human health effects due to antimicrobial resistance arising from antimicrobial use in animals. Potential ecological pathways for the flow of antimicrobial resistant bacteria and resistance determinants through the food supply and environment are diverse and complicated and this has been a logistical barrier to direct epidemiological measure of risk. Consequently, a number of indirect approaches to assessment have been developed. This paper provides some examples of risk assessments that have been conducted with and without antimicrobial use data, and identifies possible benefits and applications of quantitative antimicrobial use data for risk assessment.

Animals↗

Violence risk assessment and risk communication: the effects of using actual cases, providing instruction, and employing probability versus frequency formats.

This article describes studies designed to inform policy makers and practitioners about factors influencing the validity of violence risk assessment and risk communication. Forensic psychologists and psychiatrists were shown case summaries of patients hospitalized with mental disorder and were asked to judge the likelihood that the patient would harm someone within six months after discharge from the hospital. They also judged whether the patient posed a high risk, medium risk, or low risk of harming someone after discharge. Studies 1 and 2 replicated, with real case summaries as stimuli, the response-scale effects found by Slovic and Monahan (1995). Providing clinicians with response scales allowing more discriminability among smaller probabilities led patients to be judged as posing lower probabilities of committing harmful acts. This format effect was not eliminated by having clinicians judge relative frequencies rather than probabilities or by providing them with instruction in how to make these types of judgments. In addition, frequency scales led to lower mean likelihood judgments than did probability scales, but, at any given level of likelihood, a patient was judged as posing higher risk if that likelihood was derived from a frequency scale (e.g., 10 out of 100) than if it was derived from a probability scale (e.g., 10%). Similarly, communicating a patient's dangerousness as a relative frequency (e.g., 2 out of 10) led to much higher perceived risk than did communicating a comparable probability (e.g., 20%). The different reactions to probability and frequency formats appear to be attributable to the more frightening images evoked by frequencies. Implications for risk assessment and risk communication are discussed.

Adult↗

The morals of risk assessment.

Risk assessment of occupational cancer is in itself a hazardous occupation, involving not only assessment of animal experiments, extrapolations to humans, and human population studies, but also consideration of the political and economic factors. Cause and effect relationships are confounded by many variables in both human and animal studies. Realistic assessment should also include technology feasibility studies. "Potency" may be a spurious argument for controlling "potent" carcinogens and not "weak" carcinogens, which have the same potential. Risk assessment is not aimed at individual health outcomes; nevertheless, individual risks have to be taken into account.

Disease Models, Animal↗

Coronary plaque as a replacement for age as a risk factor in global risk assessment.

Risk assessment is assuming an increasing role for identification of high-risk persons for intensive medical intervention to reduce risk for coronary heart disease (CHD). Of particular importance is the need to identify those persons with CHD risk equivalents who can be managed with the same intensity as patients with established CHD. For example, the National Cholesterol Education Program (NCEP) recently classified diabetes as a CHD risk equivalent. The NCEP also recommended use of Framingham risk scoring in persons with multiple (2+) risk factors to uncover others without diabetes who have CHD risk equivalents. One limitation of Framingham risk scoring, however, is that age becomes the dominant risk factor after age 50. Age is a surrogate for coronary atherosclerotic plaque burden, which is the true risk factor. However, for individuals, coronary plaque burden can vary greatly at any given age. For this reason, if coronary plaque burden could be measured accurately with noninvasive techniques, the degree of plaque burden could be used to replace age as a risk factor in Framingham scoring for risk prediction. This article describes a technique whereby such a replacement can be made.

Adult↗

Risk assessment and risk management implications of hormesis.

International and US radiation protection standards are based upon risk assessment and risk management processes. The assessment of radiation risk is derived from the linear no-threshold (LNT) model. Risk management is based on more subjective value judgements. If the radiation dose-response was found to be hormetic, considerable quantitative data would be needed before current radiation protection standards would change. There would be added complexity, and consideration might have to be given to the additive effects of an individual's exposures to medical radiation and other potential carcinogens.

Adaptation, Physiological↗

Pesticide risk assessment in a lagoon ecosystem. Part II: effect assessment and risk characterization.

Ecotoxicological risk assessment for pesticides was performed on a coastal lagoon ecosystem (Orbetello lagoon, central Italy) according to the procedure described in the European technical guidance document (TGD) on risk assessment for new and existing substances. The procedure was applied to individual chemicals and to a mixture of chemicals with the same toxicological mode of action. Biomarker studies, measuring acetylcholinesterase (AchE) activity inhibition, were conducted on Zosterisessor ophiocephalus to compare the results of theoretical risk assessment with experimental measurements of ecotoxicological stress. Value and limitations of the risk assessment procedure and its application to site-specific environmental conditions are discussed. A tool crop risk index (CRI) for assessing the overall impact of pesticide use on a crop is proposed.

Acetylcholinesterase↗