The intent of this second lecture is to teach the students the basic and very close relationship between public health (PH) and health risk assessment (RA), both of which were defined and discussed briefly in Lecture 1 and are fundamental to the advances in modern epidemiology and in modern toxicology. In this lecture, the students are asked to revisit the mission of PH and to learn the impact of social choice or social interests on PH. It is a fundamental concept that much of a community’s PH mission is based upon its social values and public concerns.

The students are then asked to revisit the concept of RA and to learn the various RA tasks or activities that are ongoing today in the United States and worldwide. These example cases are provided to illustrate both the almost unlimited scope of health risks that can be assessed, and the different stages of RA that can be focused on by various health agencies.

Finally, the students are to be taught that monitoring and mitigating human exposures are the ultimate bridges between PH and RA. RA is simply the means to an end in accomplishing PH mission. That is, to ensure that the risk at issue is at a socially acceptable level, the society or a community must mitigate the exposure of its population to the toxic agent to a safe level, and maintain the exposure at or below that level.