Risk assessment process considered

Plant designs should be based on a risk assessment that considers the process and the site in detail as well as all of the principles of inherently safer operation. Earlier decisions may limit the options in... 

Because the validation of computerized systems is time consuming, expensive and resource intensive, many organizations are challenged to identify and prioritize which systems will be validated. There are organizational and system specific risk factors to consider in the regulated environment. Each organization must establish its own risk assessment process. 

The determination of the estimated levels of exposure is obviously a critical component of the risk assessment process. Both pesticide residue levels and food consumption estimates must be considered. Methods for determining exposure are frequently classified as deterministic and probabilistic methods (Winter, 2003). 

Risk assessment starts with risk identification, a systematic use of available information to identify hazards (i.e., events or other conditions that have the potential to cause harm). Information can be from a variety of sources including stakeholders, historical data, information from the literature, and mathematical or scientific analyses. Risk analysis is then conducted to estimate the degree of risk associated with the identified hazards. This is estimated based on the likelihood of occurrence and resultant severity of harm. In some risk management tools, the ability to detect the hazard may also be considered. If the hazard is readily detectable, this may be considered a factor in the overall risk assessment. Risk evaluation determines if the risk is acceptable based on specified criteria. In a quality system environment, criteria would include impact on the overall performance of the quality system and the quality attributes of the finished product. The value of the risk assessment depends on how robust the data used in the assessment process is judged to be. The risk assessment process should take into account assumptions and reasonable sources of uncertainty. Risk assessment activities should be documented. 

Risk management is the process that applies information obtained through the risk assessment process to determine whether the assessed risk should be reduced and, if so, to what extent. In some cases, risk is the only factor considered in a decision to regulate exposure to a... 

The hardest part of engineering risk assessment has turned out to be the prediction of the modes of failure. Serious accidents at nuclear installations, such as those at Three Mile Island or at Chernobyl, have been caused by modes of failure that had not been analysed at all. For example, the report of the Presidents Commission on the Accident at Three Mile Island (Presidents Commission, 1979, p9) highlighted that the concentration of the assessment process on more obvious large break scenarios meant that the eventual mode of failure, which was a result of a chain of a number of more minor events, was not even considered. Despite the use of significant resources in the design process, the risk assessment had been unable to characterize the complex system adequately, a system that was totally human-made and defined. In particular, the risk assessment process had not been able to identify modes of failure caused by humans involved in the operations of the reactor behaving in unexpected ways. 

Because chemicals regulation is risk-based there must be evidence that an identified type of harm is likely to result from use of a particular chemical (in other words that the chemical poses a significant risk) before action can be taken to restrict its production or use. However, if we consider how risk assessment of chemicals is carried out, it is apparent that current methods are not able to provide evidence that commands agreement on whether there is a risk from a chemical or not. Partly as a consequence of this, risk assessment processes have been characterized by procrastination and delay. During this delay the production and use of potentially harmful chemicals is allowed to continue. 

Improvements in pesticide residue risk assessment practices should improve the scientific basis for managing pesticide residues in foods and the FQPA provides a blueprint for making such improvements. While most of the FQPA provisions are considered in theory to represent improvements in the risk assessment process, the practical adoption of methods to comply with such... 

Risk assessors must be particularly sensitive to the potential for significantly higher exposures in areas of the world where hazardous environmental exposures are not sufficiently controlled. Compounding factors such as poverty, inadequate nutrition, and compromised health status must also be considered in problem formulation throughout the risk assessment process. 

It is remarkable how little research has been done on the perception of mixture risks. This may be explained by the fact that in real life people are generally exposed to mixtures and not to single substances. Perception studies that deal with environmental pollution implicitly include perception of mixture risks. Where scientists tend to consider mixtures as an extra complicating factor in the risk assessment process, laypersons consider mixtures a fact of life. They find it difficult to understand why scientists study effects of single substances, while in real life they are exposed to mixtures they fail to understand the complexity of research on chemical mixtures. 

One of the main challenges for risk assessors and managers is to make people aware that our knowledge on chemicals is incomplete and uncertainty is inherent to the risk assessment process, especially if mixtures are involved. This is a difficult task since the notion of uncertainty is in conflict with the traditional image of the natural sciences as a provider of unambiguous answers. Not only the general public suffers from this view, but also administrators and policy makers, who often consider uncertainty a nuisance in their search for clear answers and effective policy actions. Here lies an important task for risk assessors and communicators, that is, the development of adequate tools to identify, describe, quantify, and communicate... 

Vi 3 Risk assessment not investigated Assumes harmonised risk assessment process Limits the ability for the research to examine the detailed inter-linking of risk assessment and management activities - The research considers aspects of risk assessment that are relevant to risk management - The current focus of REACH is on risk assessment many aspects of risk management appear neglected... 

Exposure assessment is a key phase in the risk assessment process since without an exposure route even the most toxic chemical does not present a threat. All potential exposure pathways are carefully considered. Contaminant releases, their movement and fate in the environment, and the exposed populations are analyzed. 

These tools should not be considered limited in application to the initial validation effort. By keeping the traceability matrix up to date it becomes (and will remain) an important tool for assessing the impact of changes to the database, and both it and the risk assessment process are still important test planning tools as part of change control. Of course, sound change control practices are absolutely imperative for keeping an application validated. 

Being able to predict the human health risk from exposure to airborne chemicals can be complex, requiring reliable analysis of human exposure. While the basic principles of risk assessment are applicable to various conditions of exposure, characterizing how an individual s health status can significantly influence the threshold for effects can be a most challenging component of the risk assessment process. One needs to consider the overall scientific weight-of-evidence to predict whether or not an individual may be uniquely susceptible to certain... 

Risk management was defined in the NAS report as the process of weighing policy alternatives and selecting the most appropriate regulatory actions. It is considered to be separate from the risk assessment process. Risk management decisions are based on the results of the risk assessment and other concerns that are relevant to the situation. 

Consider prevention and options in the risk assessment process ... 

Information obtained from risk assessments is used to aid public health officials in developing management decisions. However, the public will often view the risks associated with an agent differently than will the scientific experts, even after costly and time-consuming risk assessment efforts have been implemented. These discrepancies may be attributable to difference in how the public and scientific conununities dehne risk, or they may stem from the fundamental lack of trust the public has toward the risk assessment process (Slovic 1991). Regardless, risk perception is an important topic that invariably must be considered before the implementation of regulations or public health management decisions. 

Risk assessment has evolved somewhat since 1983. Let us consider the early risk assessment process, called here the classical era. Hazard was considered as a simple yes or no question. Exposiu-e was used instead of the dose normally used in classic dose-response models in pharmacology studies. The mechanisms between exposure and the observed effects were usually unknown or a virtual black box. ... 

---