A Fatal Flaw in the Clean Air Act: How the Clean Air Act Fails to Adequately Regulate Ambient Concentrations of Hazardous Air Pollutants

Abstract

The Clean Air Act mandates that the U.S. Environmental Protection Agency regulate emissions of over 180 Hazardous Air Pollutants (HAPs). These HAPs are commonly used industrial chemicals and compounds with the potential to cause either cancer or other serious non-cancer health effects. Although EPA estimates that “on average, approximately 1 in every 20,000 people have an increased likelihood of contracting cancer as a result of breathing air toxins from outdoor sources if they were exposed to 2005 emission levels over the course of their lifetime,” EPA does not regulate or restrict emissions of these HAPs based on the health risks posed by ambient-air concentrations or actual exposures to these toxic substances. EPA does regulate emissions of these HAPs, but the primary regulatory tool is to impose technology-based emission controls on sources of these HAPs. Years after those controls are installed, evaluates the health risks remaining (i.e., residual risks) from facilities that emit the HAPs. Unfortunately, EPA does not evaluate these risks based on actual ambient concentrations of these pollutants; instead EPA bases their assessment on engineering calculations. EPA’s own research indicates that air pollution is posing significant health risks, particularly in urban areas. EPA should revise their program so as to restrict ambient concentrations of HAPs to levels that will provide adequate protection of public health.