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Emerging and Currently Unregulated Contaminants
EPA maintains a list of unregulated microbiological and chemical contaminants to aid in priority setting for the Agency's drinking water program. This list, referred to as the Contaminant Candidate List (CCL), identifies explicitly drinking water contaminants that might be regulated by EPA at some future date. A statistically valid set of nationwide occurrence data in finished drinking water is desirable to support a regulatory determination on a listed contaminant. EPA obtains national occurrence data for contaminants by promulgating monitoring requirements through the Unregulated Contaminant Monitoring Regulation (UCMR). However appropriate tools for such monitoring are not always readily available. Effective monitoring requires analytical methods with appropriate ease of use and sensitivity, along with scientifically appropriate approaches to sample collection, preservation, analysis and data handling. Occurrence data helps set priorities for health effects research. In addition, EPA needs a transparent, technically sound process to classify and prioritize contaminants for future CCL Lists. The National Research Council has recommended that EPA consider innovative approaches, such as Virulence Factor Activity Relationships (VFARs) as a possible tool for classifying and prioritizing pathogens for potential CCL listing. To assist OW in making CCL listing and regulation determination decisions, NERL's research program is focused on: developing and applying analytical methods to assess occurrence of CCL-related contaminants; and identifying and prioritizing contaminants for possible addition to future Contaminant Candidate Lists (CCLs).