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 (EPA) regulate emissions of over 180 Hazardous Air Pollutants (HAPs). These HAPs are commonly used industrial chemicals and compounds with the potential to cause cancer or other serious health effects. Although the 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 toxics from outdoor sources if they were exposed to 2005 emission levels over the course of their lifetime," the 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. The EPA does regulate emissions of HAPs, but the primary regulatory tool is to impose technology-based emission controls on sources of HAPs. Years after those controls are installed, the EPA evaluates the health risks remaining (i.e., residual risks) from facilities that emit the HAPs. Unfortunately, the EPA does not evaluate these risks based on actual ambient concentrations of these pollutants; instead, it bases its assessment on engineering calculations. The EPA's own research indicates that air pollution is posing significant health risks, particularly in urban areas. The EPA should revise its program so as to restrict ambient concentrations of HAPs (based on detection of HAPs where the public is actually exposed) to levels that will provide adequate protection of public health.