Multiple lines of evidence are used to estimate potential consequences of contact with the contaminated medium, both now and in the future. Conducting an ecological risk assessmentīased on the results of the planning and scoping phase, the risk assessor evaluates the frequency and magnitude of human and ecological exposures that may occur.Conducting a human health risk assessment.Here are some useful links to get started: Information needed to predict how the contaminants may behave in the future also could be collected. For example, chemical concentrations in soils could be measured around the source of a spill. Īt EPA, environmental risk assessments typically fall into one of two areas:įollowing a planning and scoping stage, where the purpose and scope of a risk assessment is decided, the risk assessment process usually begins by collecting measurements that characterize the nature and extent of the hazard in the environment. How it affects the health of humans (e.g., toxicity) or ecological receptors (e.g., fish killed by lack of oxygen).

How much contact (exposure) a person or ecological receptor has with the contaminated environmental medium, and.How much of a stressor is present in an environmental medium (e.g., soil, water, air) over what geographic area,.In general terms, risk depends on the following three factors: Other types of stressors include disease-causing microbial agents or stressful conditions such as anoxia (lack of oxygen) in surface waters. The risks might be from specific chemical contaminants such as mercury or mixtures of many chemicals such as in oil spills. EPA also estimates risks to ecological receptors, including plants, birds, other wildlife, and aquatic life. Risk Assessment BasicsĮPA uses risk assessment to characterize the nature and magnitude of risks to human health for various populations, for example residents, recreational visitors, both children and adults. Stressors may adversely affect specific natural resources or entire ecosystems, including plants and animals, as well as the environment with which they interact. While there are many definitions of the word risk, EPA considers risk to be the chance of harmful effects to human health or to ecological systems resulting from exposure to an environmental stressor.Ī stressor is any physical, chemical, or biological entity that can induce an adverse effect in humans or ecosystems.

If you have questions after reviewing this page and its links, please use the “Contact Us” form, linked on this page, for assistance. Learn about Risk Assessment A brief introduction to risk assessment is presented below.

Risk probability and effect