What Is a Human Health Risk Assessment?

A human health risk assessment is an estimate of potential health risk to individual humans who

are exposed to contaminants of concern while conducting specific activities.

What Are the Components of a Human Health Risk Assessment?

The human health risk assessment integrates four general components in making a risk estimate.

These include:

Hazard identification - an initial description of potential health effects associated

with the contaminants of concern and an estimate of acute risk if such is likely.

Exposure assessment - an estimate of the dose of a contaminant received by an

individual human under specific conditions and while conducting specific activities

(detailed within the exposure assessment).

Toxicity assessment - a summary of the human health effects associated with each

contaminant of concern and a choice of an appropriate end point (toxicity factor)

against which to judge potential risk.

Risk characterization - an estimate of potential risk to individuals based on a

comparison of the dose calculated in the exposure assessment to the end points

defined in the toxicity assessment.

What Are the Criteria for Judging Human Health Risks?

Human health risks depend on an estimate of the potential for carcinogenic risk and

noncarcinogenic risk for each contaminant. The potential for carcinogenic risk depends on an

estimate of the carcinogenic potential of a contaminant (expressed as a probability of increased

cancer risk) and the noncarcinogenic risk based on a comparison of a threshold dose for a

contaminant of concern to the dose calculated in the exposure assessment.

Chapter 4 Human Health Risk Assessment