Chapter 3: A typology of risk assessment and management methods

Chapter 3: A typology of risk assessment and management methods

As seen in Chapter 2, the uses of risk assessments are wide and varied. The risks examined in the assessment can be physical such as radiation, biological such as a genetically modified organism or pathogen, or chemical such as an immuno-toxic substance. The target/receptor to be examined in the risk assessment can vary. Human beings are the species most extensively considered in risk assessments - human health risk assessments - but other single species risk assessments are common. Many ecological risk assessments can be considered single species, since only a few types of representative organisms are selected as assessment end-points (Landis et al., 1995). The end-points examined in the risk assessment are varied. They can be mortality or morbidity in human health assessments or other single species assessments. For some ecological risk assessments, end-points may be extinction or total catch. Some ecological risk assessments use end-points that indicate biodiversity or disturbance to ecological systems.

In this Chapter, a typology of risk assessment methods in use or development will be outlined. The typology is shown in Figure 3.1 and breaks environmental risk assessment into:

• Human Health Risk Assessment
• Ecological Risk Assessment
• Applied Industrial Risk Assessment

The basis of the human health/ecological split is that although the two processes are conceptually similar (in fact ecological risk assessment has developed from human health risk assessment), the two have a differing historical development and regulatory and policy imperatives. Applied industrial applications have been separated as many of these assessments do not look in isolation at people or ecological systems. They look at real situations and tend not to be as "pure" as the first two categories. They are likely to include engineering risk assessments as part of the overall environmental risk assessments and may take an integrated approach to human and environmental risks. They are likely to lay much more importance to ensuring that the risk assessment can be used in risk management decisions as the objective is more clear-cut - to make a risk management decision intended to protect humans and the environment (and the company) within defined spatial boundaries.

It will be noted that the human health typology and the industrial use typology are more detailed than that for ecological risk assessment. This is because these are the areas in which the methodology is most developed.

The typology does not outline all the possible types of risk assessment. In the area of ecological risk assessment, there are many developing techniques and much research is being carried out to define suitable end-points. The typology of ecological risk assessment shown is that currently practised or in an advanced state of development in government or industry.

The typology for industrial application for risk assessment is based on use of the method rather than the type of method.

Figure 3.1 A Typology of Risk Assessment (source R. Fairman and C. Mead)

Reference list for this chapter