Should Perchlorate in Drinking Water be Regulated?

Abstract

The rocket fuel ingredient perchlorate has emerged over the past decade as one of the most controversial drinking water regulatory issues. Elevated concentrations have been reported in surface waters and groundwaters and in public water systems in 26 states. Perchlorate was included on the second Contaminant Candidate List (CCL2) for possible regulation under the Safe Drinking Water Act (SDWA). Every five years, the U.S. Environmental Protection Agency (USEPA) is required to determine whether to regulate at least five contaminants from the CCL. A maximum contaminant level goal (MCLG) and National Primary Drinking Water Regulation (NPDWR) are required for a contaminant on the CCL if USEPA determines that: the contaminant may have an adverse effect on the health of people; the contaminant is known to occur or there is substantial likelihood for it to occur in public water systems with a frequency and at levels of public health concern; and, regulation of the contaminant presents a meaningful opportunity for health risk reduction for people served by public water systems. This article briefly reviews a preliminary determination on perchlorate that was issued by the USEPA on Oct. 10, 2008 (USEPA, 2008).