Risk assessment biological agents

Local risk assessment may suggest that the use of PPE is appropriate in order to control the risk of biological agent exposure. Masks and skin protection may be considered and must be suitable for the task being carried out and provide a sufficient level of protection. 

Risk assessment is an empirically based process that estimates the risk of adverse effects from exposure of an individual or population to a chemical, physical or biological agent. The OECD test guidelines, the US EPA risk assessment guidelines and additional risk assessment procedures for new and existing chemicals have been published and put into use by many different countries in Europe, the Americas and Asia (United Kingdom Department of Health, 1991,1995 EC, 1994,1996 Health Canada, 1994 IPCS, 1994 Hertel, 1996). A list of assessments produced by various national and international agencies on specific chemicals is included in ECETOC/UNEP (1996). 

Risk assessment An empirically based paradigm that estimates the risk of adverse effects) from exposure of an individual or population to a chemical, physical or biological agent. It includes the components of hazard identification, assessment of dose-response relationships, exposure assessment and risk characterization. 

This chapter will address the implications of the data presented in previous chapters for assessing the risks from environmental chemical exposures. WHO/IPCS has defined risk assessment as an empirically based paradigm that estimates the risk of adverse effects from exposure of an individual or population to a chemical, physical, or biological agent. As shown in Figure 21, it includes the components of hazard identification (Is there an adverse effect ), dose-response assessment (How severe is it ), exposure assessment (What is the level of exposure ), and risk characterization (What is the risk ) (NRC, 1983 IPCS, 2000). 

Figure 7.4 Typical frequency distribution of a population response to an equivalent dose of a biologically active agent. This type of response represents the variability that occurs within biological systems and is the basis for the concept of dose response in pharmacology and toxicology. This figure demonstrates that within any population, both hyporeactive and hyperreactive individuals can be expected to exist and must be addressed in a risk assessment.

Exposure assessment The component of an ecological risk assessment that estimates the exposure resulting from a release or occurrence in a medium of a chemical, physical, or biological agent. It includes estimation of transport, fate, and uptake. 

Human health risk assessments with chemicals and other agents (biological, physical) typically follow a paradigm that involves four steps - hazard identification, dose-response assessment, exposure assessment, and risk characterization. The process was recommended by the US National Research Council in the 1980s, and is usually applied to a single agent and exposures associated with one or more routes (oral, dermal, inhalation). This has been more recently referred to as aggregate exposure and risk assessment. 

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