Is it true that only a source of contamination and a receptor are necessary for a human risk to occur?

Human risk assessment involves understanding the interaction between sources of contamination and receptors, but it is not sufficient to state that only these two elements are needed for a risk to occur. In addition to a source of contamination and a receptor, the pathway through which the contamination can affect the receptor is also crucial.

First, a source of contamination refers to any substance or activity that can potentially cause harm, such as a leaking heating oil tank. The receptor is a person or population that may be affected by exposure to this contaminant. However, without an exposure pathway — the means by which the contaminant travels from the source to the receptor — a risk cannot effectively manifest. This could include various routes such as air, soil, water, or food.

Understanding this triad (source, receptor, and pathway) is essential in evaluating potential human health risks. If any element is missing, the risk of exposure is significantly decreased or does not exist at all. Therefore, the statement that only a source of contamination and a receptor are necessary for human risk to occur is not accurate.