Microbiological and Chemical Exposure Assessment
Exposure to certain kinds of bacteria, molds, viruses, and single-celled organisms can lead to health risks for human beings. EPA microbiologists study how these organisms and pathogens spread in areas where people live, work, and play—and how we can limit our exposures to the types that can be hazardous to our health. EPA scientists have developed methods for detecting, characterizing and measuring bacteria, viruses and protozoa in drinking water, ground water and recreational water. DNA and immuno-based methods, as well traditional cultural methods, are used to measure hazardous bacteria, viruses, fungi and protozoa. Analytical quantitative methods are developed to measure human risk factors associated with inhalation, ingestion and dermal pathways.
Developing methods to detect viruses in water
Viruses, such as enteroviruses and noroviruses, can spread in groundwater systems but are difficult to detect. EPA scientists have developed a way to quickly screen water for these contaminants.
Saliva-based measurement method for detecting exposure to waterborne pathogens
Exposure scientists at EPA have developed a quick, inexpensive method to sample swimmers’ saliva to understand links between exposure to pathogens in water and human health. Using swabs of saliva, which can be collected quickly and non-invasively, scientists can look for specific antibodies created by the immune system in response to exposure to certain microbes.
Developing and validating same-day method for monitoring recreational waters
Traditional methods of recreational water testing require at least 24 hours for results, which means beach managers may not know to issue swimming advisories until after a bacterial outbreak. A new method developed by EPA scientists cuts the laboratory testing time down to just four hours.
Understanding risks from pathogens in piped water systems
Legionella bacteria can grow in piped water systems and lead to respiratory infections in humans. EPA scientists are studying how these bacteria spread in plumbing systems, and how to reduce human exposure to them.
- EPA Exposure Research
- EPA Microbiology Resources
- EPA’s Method 1615: New ways to measure viruses in water
- Fact Sheet: Saliva-based assays for linking gastrointestinal illness with waterborne pathogens
- Water Research: "Legionellae in engineered systems and use of quantitative microbial risk assessment to predict exposure." Buse, Schoen, Ashbolt. 2011.