Microbiological and Chemical Exposure Assessment
Given water’s fundamental importance to human life, it’s crucial for scientists to understand how we can be exposed to microbial and chemical threats in our drinking water systems and recreational waters. EPA microbiologists are studying ways that chemicals and microbes can travel through and grow in ground water, drinking water, and recreational water. These scientists have worked to develop new, scientifically-proven methods to test drinking water for viruses, find unregulated chemicals and other contaminants in drinking and ground water, and find bacteria in recreational water and plumbing systems. These methods are available for use by water managers across the country to ensure that both drinking and recreational waters are safe.
Using mussels to detect microbial contamination of ambient water
Mussels and other bivalves are very efficient natural filtration devices that can filter up to 5 liters of water per hour to feed on microscopic plants and nutrients in water. EPA scientists are taking advantage of this ability by developing a low cost and effective concentration method using native and invasive species, like Blue mussels and Asian clams to collect an array of microbial pathogens from water.
Sample preparation techniques for concentrating microbes from water
Methods for detecting low concentrations of microorganisms in the environment are needed to understand the risk posed by waterborne pathogens. EPA scientists are investigating several alternative approaches for concentrating microbes from water more effectively and increasing the range of microbes that can be isolated simultaneously. This work has resulted in the identification of low cost alternative sample concentration techniques.
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.
Analytical methods for measuring drinking water contaminants
Many of the unregulated contaminants in drinking water are difficult to detect with traditional testing methods. EPA scientists are using cutting-edge technology to develop new ways of testing water for these chemicals.
How common are contaminants in treated and untreated drinking water?
Drinking water has the potential to contain traces of unregulated contaminants. To develop strategies for protecting human health, EPA needs to understand the prevalence of these contaminants in both treated and untreated drinking water. Improvements in analytical instrumentation now allow scientists to measure pollutants at very low concentrations. EPA scientists are conducting research to understand just how common these contaminants are.
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 at specific antibodies created by the immune system in response to exposure to certain microbes.
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’s Method 1615: New ways to measure viruses in water
- Drinking water methods developed by EPA's Exposure Research Program
- New EPA method for detecting semivolatile organic compounds in drinking water
- Fact Sheet: Saliva-based assays for linking gastrointestinal illness with waterborne pathogens
- EPA Microbiology Resources