Drinking Water Test Results: PFAS Contamination

Testing Methodology

We tested drinking water at three different locations across Washington, DC. We used Cyclopure PFAS Water Test Kits, which were recommended to us by multiple experts, including Upper Potomac Riverkeeper, Brent Walls. The Cyclopure PFAS Water Test Kit can detect a total of 55 per-and polyfluoroalkyl substances. The Cyclopure test kits quantify PFAS concentration to a level of accuracy down to 1-2 parts per trillion. 

Testing Procedures:
Researchers wore gloves at all testing locations, allowed the water in the Cyclopure tests to filter out through the DEXSORB absorbent pad for 20-30 minutes, used room temperature tap water for each test, and did not shake the tests until the last few drops of water were left in the test containers. All tests were immediately put back into their boxes. 

We tested tap water from: 

  • Cassell Residence Hall at American University (4400 Massachusetts Ave NW, Washington, DC 20016) in the Spring Valley Neighborhood of Northwest DC. 
  • La Plaza Mexican & Salvadorian Cuisine (629 Pennsylvania Ave. SE #4303, Washington, DC 20003) in the Capitol Hill Neighborhood.
  • Anacostia Neighborhood Library (1800 Good Hope Road SE, Washington,  D.C.  20020) in the Anacostia Neighborhood of Southeast DC.

Results

Our water test results detected six different PFAS present in each of the three different locations we tested. The specific chemicals detected at each location were PFOS, PFOA, PFBS, PFHxS, PFHxA, and PFPeA.

These testing results are not a representative sample of PFAS contamination in DC drinking water.

Map produced by researchers using ArcGIS

PFOS is one of the most widely used and studied PFAS along with PFOA. Studies looking at individuals who have been exposed to PFOS have indicated connections between exposure to PFOS and impacts on the immune system, cardiovascular system, human growth and development, and cancers. The interim updated Health Advisory from the EPA for PFOS is 0.02 parts per trillion.

PFOA is another widely used and studied PFAS along with PFOS. Studies looking at individuals who have been exposed to PFOA have indicated connections between exposure to PFOA and impacts on the immune system, cardiovascular system, human growth and development, and cancers. The interim updated Health Advisory from the EPA for PFOA is 0.004 parts per trillion.

PFBS, or perfluorobutanoic acid, is regarded as an alternative to PFOS in chemical and product manufacturing. PFBS has been linked to adverse impacts on human health. It has been associated with health effects on development, the thyroid, the reproductive system, and the kidney. The final Health Advisory from the EPA for PFBS is 2,000 parts per trillion.

Studies demonstrate that PFHxS may be a neurotoxin with similar health effects to PFOA and PFOS. It has been linked to high cholesterol, developmental issues, and effects on the liver and immune system. PFHxS are part of the EPA’s Hazard Index and can be calculated here. 

PFHxS have been used in aqueous film-forming foam (AFFF) and have been discharged into water by industry and wastewater treatment plants.

PFHxA is a breakdown product of other PFAS chemicals. Although it has yet to be found as a carcinogen, PFHxA exposure can be linked to harm in the kidneys such as increased kidney weight. PFHxA are most frequently found in agricultural crops and has been detected in household dust, groundwater, and drinking water. The Hazard Index PFHxA in water is 1. 

PFPeA is part of the perflourinated chemicals and has been linked to similar health effects as PFOS. It is also one of the less common PFAS chemicals.

Limitations

Due to limits in funding and time, we were only able to test three locations in the Washington, DC area. This is not a representative sample of PFAS in DC tap water. We are not able to draw any conclusions about the scale of PFAS contamination of DC tap water. Instead, we would classify our water testing as exploratory sampling. We recommend further research and water testing both in Washington, DC and nationwide. Additionally, we call for transparency and data availability in other entities testing for PFAS. This would ensure both researchers and the public will have access to information to make informed decisions about public health.

While it is clear that PFAS contamination is present in DC drinking water, more research must be done to examine the scale and scope of contamination. PFAS are an incredibly complex issue and much about them is still unknown. In particular, further research should be conducted on potential environmental justice issues connected to PFAS contamination. Public health, environmental health, and justice are inextricably linked and more work must be done to interrogate how PFAS may impact different groups disproportionately.

Recommendations for Future Research

To further expand on our research, more comprehensive testing and analyses of PFAS, both in DC and nationwide drinking water, should be conducted. In addition, the possible links between exposure to PFAS and other demographic factors including location, socioeconomic status, and race should be explored. This type of research has not been conducted at the national level or in a scope specific to Washington, DC. Such exploration and analysis would allow for a better understanding of how PFAS impacts people across the U.S. and Washington, DC. In particular, testing and analyzing a representative sample of nationwide drinking water, something that has not yet been done, would provide important context for how PFAS is impacting the U.S. population. Testing a representative sample of drinking water in Washington, DC would also allow for a more developed understanding of how contamination affects DC residents specifically.