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PFAS in Drinking Water
The Illinois Environmental Protection Agency (Illinois EPA) recently tested the City of Aurora drinking water supply for compounds known as Per- and Polyfluoroalkyl Substances (PFAS) as part of a statewide study of community water supplies.
Why is this important?
PFAS are a group of approximately 5,000 human-made substances that have been manufactured in the United States since the 1940s for their unique oil and water-resistant properties and have been utilized for a variety of applications ranging from water and stain-proofing to firefighting. This has resulted in PFAS being released into the air, water, and soil. Most people are exposed to PFAS compounds from water, food, and consumer products.
PFAS can be found in:
• Food packaged in PFAS-containing materials (fast food containers, lunch meat paper, disposable plates and bowls), processed with equipment that uses PFAS, or grown in PFAS-contaminated soil or water.
• Commercial household products, including stain- and water-repellent fabrics, nonstick coated cookware and products (e.g., Teflon), polishes, waxes, paints, and cleaning products.
• Fire-fighting foams which are a major source of groundwater contamination at airports and military bases where firefighting training occurs.
• Workplace, including production facilities or industries (e.g., chrome plating, electronics manufacturing, oil recovery) that use PFAS.
• Clothing and textile fabrics which have stain- and water-resistant properties.
• Cosmetics and personal care products such as shampoos, conditioners, sunscreens, cosmetics, and dental floss.
• Living organisms, including fish, animals and humans, where PFAS have the ability to build up and persist over time.
Some PFAS have been phased out of production due to environmental and human health concerns, yet they persist in the environment and may contaminate surface and ground waters. Production for two of the most common compounds within this class, perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) was discontinued in the United States in the early 2000s. PFAS are made up of chains of carbon and fluorine linked together. The carbon-fluorine bond is one of the shortest and strongest bonds in nature and does not easily break down under natural conditions. For this reason, PFAS are often referred to as “forever chemicals” due to their chemical bonding and persistence in the environment.
Neither the state Illinois EPA nor the federal United States Environmental Protection Agency (USEPA) have yet developed enforceable drinking water standards for PFAS. In the interim, the Illinois EPA has recently developed health-based Draft Guidance Levels for the small number of PFAS for which there is appropriate information to do so (shown in table below). There is not enough information currently available for scientists to develop health-based Draft Guidance Levels for all PFAS. Draft Guidance Levels for drinking water are intended to be protective of all people consuming the water over a lifetime of exposure. It is important to understand that Draft Guidance Levels are not regulatory limits for drinking water. Rather, the Draft Guidance Levels are benchmarks against which sampling results are compared to determine if additional investigation or other response action is necessary. More information on the Illinois EPA’s health advisory can be found at the following: https://www2.illinois.gov/epa/topics/water-quality/pfas/Pages/pfas-healthadvisory.aspx.
Illinois EPA Health Advisory Levels for PFAS
Health-Based Draft Guidance Level - (ng/L)
The USEPA and the Illinois EPA are evaluating PFAS and may regulate PFAS in the future. Currently, the USEPA is gathering data in all the states. As part of a state-wide PFAS drinking water investigation, the City of Aurora was notified in September 2020 that the IEPA would be testing all community water supplies in Illinois for the presence of PFAS. In November 2020, the Illinois EPA collected an initial finished water sample at Aurora’s water treatment plant. In December 2020, two discrete, duplicate follow-up samples were also collected. All samples were tested for 18 PFAS compounds and the results were reported to the City of Aurora via letter by Illinois EPA on January 19, 2021.
IEPA PFAS TESTING RESULTS FOR THE CITY OF AURORA
Hexafluoropropylene oxide dimer acid
ND = Not Detected (< 2.0 ng/L)
ng/L = parts per trillion (ppt)
Three PFAS compounds were detected in the initial November sample, with only two compounds detected in both confirmation samples collected in December. One compound, PFOA was detected at 2.1 ng/L in the November sample, but was not detected in the December samples. The November result of 2.1 ng/L is slightly above the Draft Guidance Level guidance level of 2.0 ng/L for PFOA. The other two compounds detected (PFBS and PFHxA) were significantly below the associated Draft Guidance Levels. Results are shown in tabular form above.
As of February 2021, about 30% of the 1,453 community water supplies in Illinois have been tested. Of those tested thus far, 13 have exceeded the Draft Guidance Level for at least one of the PFAS compounds. The statewide PFAS sampling results are available on the Illinois EPA’s PFAS informational website at http://www2.illinois.gov/epa/topics/water-quality/pfas/. The Illinois EPA may use the health advisory guidance levels and data gathered from the statewide drinking water investigation in the potential development of enforceable drinking water standards for PFAS known as Maximum Contaminant Levels (MCL’s).
In response to the PFAS testing data and in accordance with IEPA recommendations, the City of Aurora is taking immediate action to inform consumers, initiate further monitoring to better understand the prevalence and occurrence of PFAS compounds, and evaluate options to reduce exposure levels. Beginning in February 2021 the city will begin monthly testing of raw water and finished water for PFAS, exceeding the IEPA recommendation for quarterly monitoring. This testing will lead to further investigation and testing of methods to reduce or eliminate PFAS compounds in the finished water provided to customers.
As part of the USEPA’s Unregulated Contaminant Monitoring Rule 3 (UCMR3), the USEPA identified PFAS to be studied. Accordingly, in 2014 and 2015 samples of Aurora finished water were collected and analyzed. Samples were additionally collected and analyzed in 2019 and early 2020. All testing results indicated no detection of either PFOA or PFOS in the City’s finished water supplied to customers.
In 2016, the USEPA issued a Health Advisory for PFOA & PFOS for Drinking Water. At that time, the Health Advisory established a combined level at 70 ng/L for PFOA and PFOS from drinking water. The USEPA stated that the health advisory level offered a margin of protection for all Americans throughout their life from adverse health effects resulting from exposure to PFOA and PFOS in drinking water.
Studies indicate that exposure to high levels of PFAS over time may cause adverse health effects. The detection of levels of PFOA that exceed the recently established Draft Guidance Level does not necessarily indicate a fundamental change in the water quality, but rather new testing in response to emerging research and possible future regulation of PFAS. International research on the potential health effects associated with PFAS is ongoing.
Customers concerned about exposure to PFAS in drinking water can minimize the risks by utilizing bottled water that has been tested for PFAS or installing filters or treatment systems certified by the American National Standards Institute (ANSI) or NSF International for the reduction of PFAS. Boiling water does not destroy PFAS.
For information on PFAS compounds, including possible health effects, please visit the following websites:
Illinois EPA: https://www2.illinois.gov/epa/topics/water-quality/pfas/Pages/default.aspx
Centers for Disease Control and Prevention: https://www.cdc.gov/biomonitoring/PFAS_FactSheet.html
Agency for Toxic Substances and Disease Registry (ATSDR): https://www.atsdr.cdc.gov/pfas/index.html
The Interstate Technology and Regulatory Council (ITRC): https://pfas-1.itrcweb.org/
The City of Aurora Water Production Division may be contacted at (630) 256-3250.
If you have questions regarding PFAS in drinking water, please contact the below listed Illinois state contacts at the Illinois EPA and Illinois Department of Public Health:
Illinois Environmental Protection Agency
Barb Lieberoff, Office of Community Relations
Illinois Department of Public Health
Brian Koch, Division of Environmental Health