Informing regulatory decisions using national occurrence data

As part of its regulatory development process, the US Environmental Protection Agency (USEPA) is charged with selecting the appropriate contaminants to regulate. The Safe Drinking Water Act (SDWA) lists three specific criteria for health effects, occurrence, and risk reduction that the USEPA must follow when identifying new contaminants for regulation. This article analyzes USEPA's past regulatory decisions and summarizes the underlying occurrence data used to support those decisions. This article also summarizes the occurrence data that will be used by USEPA in its third round of regulatory determinations scheduled to be proposed sometime in 2012.