The meaning of “risk assessment” can be elusive as many people and professions use the term in different ways and for different purposes.  So it is always useful to understand the context in which the term is being used.

Here we refer to the concept in the field of environmental risk assessment.  In its Code of Practice: Environmental Risk Assessment For Unregulated Waste Disposal Sites, the Republic of Ireland (RoI) EPA defines risk assessment as a means of considering “the likelihood of occurrence and the consequences of the occurrence of an event. It represents a systematic means of determining and evaluating the nature, effect and extent of exposure a vulnerable receptor may experience in relation to a particular hazard.”   In such approaches, the focus is on identifying the source(s) of contaminants and their toxicity, the pathway by which the contaminants can reach a “receptor,” i.e., people, animals, the environment.  Pathways typically are air, surface or ground water, sediments in water, and contact with solid materials, including soils.

A chemical can be hazardous, or dangerous, because it has toxic properties, for example dioxin.  But if the dioxin sits in a safe container in a lab and does not come into contact with any living thing, then it presents no actual risk.  If the dioxin is released into the air, say from an industrial explosion, then a risk assessment would evaluate the toxicity of the dioxin, the level of dioxin released, whether any person or animals or the environment were exposed to the dioxin and to what extent.

The environmental risk assessment is used by government agencies, and others, to determine what risks exist at a particular site or facility or as a result of some event, such as an explosion and it serves as the basis for decision-making on how to eliminate or reduce the risks.

Some further ideas to explore on Risk Assessment:

See if can identify some chemical or contaminant to which people in your home, school, or community are exposed.

Learn as much as you can about the chemical or contaminant, especially its dangers.

See if you can measure or estimate the level of exposure to which anyone was exposed and how the chemical or contaminant got to the people.

Now try to assess the extent or level of risk presented.

Finally, what can you do to eliminate or substantially reduce the risk.

Resources:

For an example of a risk assessment applied to genetically modified micro-organisms, see www.epa.ie/whatwedo/licensing/gmo/contained/risk/

EU, Environmental Risk Assessment – Approaches, Experiences and Information Sources (Environmental issue report No 4, 24 Mar 1998) www.eea.europa.eu/publications/GH-07-97-595-EN-i2/chapter1h.html

US EPA www.epa.gov/riskassessment/