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Standards for Assessing the Safety of Recreational Waters from Fecal Contamination


Contamination of waterways with fecal material leads to the dissemination of pathogens and antibiotic-resistant bacteria that can have serious impacts on human and environmental health. 


Over 286 million Americans get their tap water from a community water system.  To assure the water safety, bacterial testing must be performed regularly. 

The EPA is responsible for protecting human and environmental health through the safeguard of recreation waters. To do so, molecular methods for identifying host-associated genetic markers of fecal pollution have been developed at EPA. These qPCR methods are being adopted by state and local public health agencies, as well as commercial entities.    

NIST, in collaboration with the EPA, is developing a DNA reference material to assess the analytical performance of EPA-developed water quality quantitative polymerase chain reaction (qPCR) testing methods. The reference material will consist of 5 levels of plasmid DNA within a stable matrix that can be stored refridgerated and used as-is.

Major sources of contaminants include human derived sources, such as sewage leaks or combined sewer overflows; and agricultural sources, such as confined animal feeding operations and manure amendment of agricultural fields. In some watersheds, birds, deer, and other wildlife may also contribute to aquatic fecal loads. Reduction of aquatic fecal loads and increased protection of human and environmental health depend on distinguishing which of the many possible contaminating sources impact a body of water. 

Created March 6, 2020, Updated July 5, 2022