WATER QUALITY FACT SHEET: PERFLUOROOCTANOIC ACID (PFOA) AND PERFLUOROOCTANESULFONIC ACID (PFOS)

Chemical Properties: • PFOA and PFOS are fluorinated organic chemicals that are part of a larger man-made chemical group referred to as per- and polyfluoroalkyl substances (PFAS), which are resistant to heat, water, and oil. • The chemicals have been used in consumer products such as carpets, clothing, fabrics for furniture, paper packaging for food, and other materials (e.g., cookware) designed to be waterproof, stain- resistant or non-stick. • They also have been used in fire-retarding foam at airfields, military bases, and various industrial processes. • PFOA and PFOS have been the most extensively produced and studied PFAS. PFAS also includes GenX chemicals and perfluorobutane sulfonic acid (PFBS) which require further study. • PFAS tends to accumulate in groundwater with contamination typically localized and associated with facilities where the chemicals were produced or used to manufacture other products.

Health Concerns: • In 2016, the United States Environmental Protection Agency (USEPA) issued a lifetime health advisory for PFOA and PFOS for drinking water. Municipalities were advised that they should notify their customers of the presence of levels over 70 ppt (0.07 µg/L) in community water supplies. • Studies indicate that PFOA and PFOS may result in adverse health effects including developmental effects to fetuses during pregnancy or breastfed infants, cancer, liver effects, immune effects, thyroid effects, and cholesterol changes.

Regulatory Considerations: • The USEPA has not regulated PFOA and PFOS. There is no Federal MCL or MCLG. • In August 2019, the California State Water Resources Control Board Division of Drinking Water (DDW) updated notification levels for PFOA and PFOS from 14 ppt to 5.1 ppt for PFOA and from 13 ppt to 6.5 ppt for PFOS. • Notification levels are the non-regulatory standards for requiring notification and further monitoring. These levels are based on updated health recommendations from California Office of Environmental Health Hazard Assessment (OEAHHA). • The response level for PFOA and PFOS remains a total concentration of 70 ppt for both contaminants. • The State Water Board has requested that OEHHA develop public health goals for both PFOA and PFOS.

Analytical Methods: • EPA Method 537 was used to analyze for 6 perfluorinated compounds during the third Unregulated Contaminant Monitoring Rule (UCMR3). Minimum reporting levels (MRLs) for PFOA and PFOS were 0.02 and 0.04 µg/L, respectively. • In November 2018, DDW identified EPA Method 537.1 as the valid method for drinking water analysis. This method reduces method detection levels and provides results for 18 PFAS including PFOA and PFOS. EPA Method 537 Rev. 1.1 (2009) is currently being phased out.

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Occurrence in CCWD Water and Other Waters: • CCWD monitored for PFOA and PFOS along with 4 other perfluorinated compounds in 2013 as part of the UCMR3 with no detections. Results are shown in the table below.

CCWD UCMR 3 Results Bollman WTP Randall-Bold WTP Compound MRL 1 Mar Jun Sep Dec Mar Jun Sep Dec (µg/L) Perfluorobutanesulfonic Acid (PFBS) 0.09 ND ND Perfluoroheptanoic Acid (PFHpA) 0.01 ND ND Perfluorohexanesulfonic Acid (PFHxS) 0.03 ND ND Perfluorohexanenanoic Acid (PFNA) 0.02 ND ND Perfluorooctanesulfonic Acid (PFOS) 0.04 ND ND Perfluorooctanoic Acid (PFOA) 0.02 ND ND 1 Minimum reporting limit (MRL)

• DDW ordered public water systems to sample drinking water supply wells near landfills or airports, locations where these chemicals are believed to be especially prevalent. Water systems were also ordered to test wells near previous contaminated sites. • Results from the first quarter of monitoring were released to the public in October 2019.

References: 1. California Office of Environmental Health Hazard Assessment, 2016. Notice of Intent to List Perfluorooctanoic Acid (PFOA) and Perfluorooctane Sulfonate (PFOS), September. https://oehha.ca.gov/proposition-65/crnr/notice-intent-list-perfluorooctanoic-acid-pfoa-and- perfluorooctane-sulfonate 2. California State Water Resources Control Board – Division of Drinking Water, 2019. Perfluorooctanoic Acid (PFOA) and Perfluorooctane Sulfonate (PFOS), April. https://www.waterboards.ca.gov/drinking_water/certlic/drinkingwater/PFOA_PFOS.html 3. United States Environmental Protection Agency, 2016. Drinking Water Health Advisory for Perfluorooctane Sulfonate (PFOS), May. 4. United States Environmental Protection Agency, 2016. Drinking Water Health Advisory for Perfluorooctanoic Acid (PFOA), May. 5. United States Environmental Protection Agency, 2016. Fact Sheet: PFOA & PFOS Drinking Water Health Advisories, US Environmental Protection Agency, November. 6. United States Environmental Protection Agency, 2017. Technical Fact Sheet - Perfluorooctane Sulfonate (PFOS) and Perfluorooctanoic Acid (PFOA), US Environmental Protection Agency, November.

Water Quality Fact Sheet – PFOA and PFOS November 2019