EPA researchers developed a new rapid method for testing beach water quality that will protect Americans' health by reducing the time for detecting bacterial contamination from 24 hours to just two. In tests done at two Great Lakes beaches, researchers verified that the more rapid method accurately predicts possible adverse health effects from bacterial contamination. The results of the study will help support new federal criteria and limits for water quality indicators in recreational waters.
The paper, published in the January 2006 issue of "Environmental Health Perspectives," presents some of the first findings of the National Epidemiological and Environmental Assessment of Recreational (NEEAR) Water Study. NEEAR is a multi-year research project being conducted by EPA and the Centers for Disease Control and Prevention (CDC). The first phase of the project assessed the new method in the Great Lakes. The next phase will collect and analyze similar data at ocean beaches.
"This research provides a new DNA-based tool that can be used by Great Lakes beach managers to test the water quality in the morning and make same-day decisions on beach warnings or closing—often before people even go into the water to swim," said George Gray, assistant administrator for the Office of Research and Development. "This tool is an excellent real-world example of how EPA is working to protect the health of people. We can provide them with useful, practical information with which to make decisions that affect their lives and health."
Approximately 89 million Americans enjoy swimming in recreational waters each year. If the water is contaminated with bacteria or other pathogens from sewage, it can lead to unwanted health effects, leading to gastrointestinal, respiratory, eye, and ear illnesses. This study shows a strong link between bacteria (that originates with sewage) identified using the new technology and the health of swimmers.
The research used DNA analysis to quantify two types of bacteria, enterococci and bacteroides, in the water at two beaches on Lake Michigan and Lake Erie. The results of the water quality tests were then correlated to health surveys of people who swam at the beaches by interviewing people as they left the beach and again by telephone 10 to 12 days after their beach visit.