Integrating Susceptibility Into Environmental Policy
An Analysis of the National Ambient Air Quality Standard for Lead
Published in: International Journal of Environmental Research and Public Health, v. 9, no. 4, Mar. 2012, p. 1077-1096
Posted on RAND.org on March 01, 2012
Read MoreAccess further information on this document at International Journal of Environmental Research and Public Health
This article was published outside of RAND. The full text of the article can be found at the link above.
Susceptibility to chemical toxins has not been adequately addressed in risk assessment methodologies. As a result, environmental policies may fail to meet their fundamental goal of protecting the public from harm. This study examines how characterization of risk may change when susceptibility is explicitly considered in policy development; in particular we examine the process used by the U.S. Environmental Protection Agency (EPA) to set a National Ambient Air Quality Standard (NAAQS) for lead. To determine a NAAQS, EPA estimated air lead-related decreases in child neurocognitive function through a combination of multiple data elements including concentration-response (CR) functions. In this article, we present alternative scenarios for determining a lead NAAQS using CR functions developed in populations more susceptible to lead toxicity due to socioeconomic disadvantage. The use of CR functions developed in susceptible groups resulted in cognitive decrements greater than original EPA estimates. EPA's analysis suggested that a standard level of 0.15 μg/m3 would fulfill decision criteria, but by incorporating susceptibility we found that options for the standard could reasonably be extended to lower levels. The use of data developed in susceptible populations would result in the selection of a more protective NAAQS under the same decision framework