EPA uses the Unregulated Contaminant Monitoring Rule (UCMR) to collect data for contaminants that are
suspected to be present in drinking water and do not have health-based standards set under the Safe Drinking
Water Act (SDWA).
Occurrence data are collected through UCMR to support the Administrator's determination of whether to regulate particular contaminants in the interest of protecting public health.
The UCMR program was developed in coordination with the CCL.
What are the public health benefits of UCMR?
UCMR provides EPA and others with scientifically valid data on the occurrence of these contaminants in drinking water. This permits assessment of the population being exposed and the levels of exposure.
This data set is one of the primary sources of occurrence and exposure information the Agency uses to develop regulatory decisions for emerging contaminants.
EPA releases data for first round sample results of UCMR5. For more information CLICK HERE.
The fourth Unregulated Contaminant Monitoring Rule (UCMR 4) was proposed on December 11, 2015. The proposal outlines monitoring for 30 chemical contaminants between 2018 and 2020 using analytical methods developed by EPA and consensus organizations. This monitoring provides a basis for future regulatory determinations and, as warranted, actions to protect public health.
The third Unregulated Contaminant Monitoring Rule (UCMR 3) was published on May 2, 2012. UCMR 3 requires monitoring for 30 contaminants (28 chemicals and two viruses) between 2013 and 2015 using analytical methods developed by EPA, consensus organizations or both. This monitoring provides a basis for future regulatory actions to protect public health.
The second Unregulated Contaminant Monitoring Rule (UCMR 2) was published on January 4, 2007. UCMR 2 required monitoring for 25 contaminants between 2008 and 2010 using analytical methods developed by EPA, consensus organizations, or both. This monitoring provides a basis for future regulatory actions to protect public health.
The 1996 Safe Drinking Water Act (SDWA) amendments require that once every five years EPA issue a new list of no more than 30 unregulated contaminants to be monitored by public water systems (PWSs). The first Unregulated Contaminant Monitoring Rule (UCMR 1) was published on September 17, 1999, and through supplemental actions on March 2, 2000, and January 11, 2001.
UCMR 1 required monitoring for 26 contaminants between 2001 and 2003 using analytical methods developed by EPA, consensus organizations, or both. This monitoring provides a basis for future regulatory actions to protect public health.
EPA reviews contaminants that had been evaluated through existing prioritization processes, including previous UCMR contaminants and the CCL. Additional contaminants may be identified based on current research on occurrence and health effect risk factors.
Chemicals that are not registered for use in the United States, do not have an analytical reference standard, or do not have an analytical method ready for use are generally removed from consideration.
EPA further prioritizes remaining contaminants based on more extensive health effects evaluations, typically performed by the Office of Water's Office of Science and Technology. The procedures for evaluating health effects were developed to support the ranking of contaminants for future CCLs.
For more information about the Unregulated Contaminant Monitoring Rule please refer to the EPA's Website
FACT SHEET ON FLUORINATED ORGANIC CHEMICALS (PFOA & PFOS) IN DRINKING WATER
PFOA and PFOS are fluorinated organic chemicals that are part of a larger group of chemicals referred to as perfluoroalkyl substances (PFASs). PFOA and PFOS have been the most extensively produced and studied of these chemicals. They have been used to make carpets, clothing, fabrics for furniture, paper packaging for food and other materials (e.g., cookware) that are resistant to water, grease or stains. They are also used for firefighting at air-fields and in a number of industrial processes.
To view EPA's Fact Sheet please click here: Fact Sheet - PFOA & PFOS Drinking Water Health Advisories
FACT SHEET ON LITHIUM
Lithium is a naturally occurring element that may be found at higher concentrations in certain parts of the country where geologic formations contain lithium salts. Lithium has numerous commercial uses including as a pharmaceutical drug, an industrial chemical catalyst, a sanitizing agent for swimming pools, and increasingly, as a component of lithium-ion batteries for electronics and electric vehicles.