Drinking Water Contaminants Exposure and Health Risks Research

Exposure to contaminants from drinking water distribution systems can occur through a number of pathways. EPA research is advancing the scientific understanding of how exposure to contaminants can occur from water systems and what the potential human health risks are from exposure.

Particular emphasis is being placed on contaminants currently regulated under the National Primary Drinking Water Regulations (NPDWR) or contaminants on the Drinking Water Candidate Contaminant List (CCL). Contaminants on the CCL are those that are currently not subject to any proposed or promulgated NPDWR but are known or anticipated to occur in public water systems.

Research Efforts

• Characterizing potential exposure pathways and consequences of contaminants in drinking water systems, including on-site plumbing. EPA researchers will focus on regulated and priority unregulated disinfection byproducts (DBPs), chemical and microbial CCL contaminants lacking health data, emerging natural and anthropogenic chemicals of concern, such as antibiotics, and chemical mixtures.
• Using physiological and biokinetic models to evaluate the potential for and the impact of exposure to drinking water contaminants. This includes evaluating multiple potential routes of exposure. Evaluations are focused on dose and toxicity and the potential for increased health risk resulting from exposure to mixtures, such as in vulnerable populations.
• Developing and evaluating analysis and assessment methods, models, and tools. These include sensitive, rugged analytical chemistry methods for contaminants selected for monitoring under the Unregulated Contaminants Monitoring Rule and computational models, such as machine learning, to determine and predict occurrence and co-occurrence patterns of groups of chemicals.
• Generating research data to inform the development of a risk-based model that integrates disinfection byproducts and microbial risk with disinfection scenarios.

Related Research

• Research on methods to measure waterborne contaminants to minimize health risks
• Saliva-based exposure assays for detecting exposure to waterborne pathogens
• Advancing lead exposure and biokinetic models
• Modeled impacts of drinking water lead reduction scenarios on children’s exposures and blood lead levels
• Microbiological and chemical exposure assessment: water
• Treatment and control of drinking water contaminants research