PFAS Monitoring

What are the PFAS (Per- and polyfluoroalkyl substances) levels in Hillsborough County’s drinking water?

2013-2014 UCMR3 Sampling

PFAS (Per- and polyfluoroalkyl substances) monitoring was completed by the County under the United States Environmental Protection Agency (EPA) Unregulated Contaminant Monitoring Rule 3 (UCMR3). Under UCMR 3 our utility collected samples from our larger water systems for four (4) quarters starting in October 2013 and ending in July 2014.

All Hillsborough County Utility samples for PFAS chemicals under UCMR 3 were below the detection levels.

 

  1. PFOA / Perfluorooctanoic acid
    • Detection level (parts per trillion): < 20
    • 2016 USEPA Health Advisory Level (parts per trillion): 70
  2. PFOS / Perfluorooctanesulfonic acid
    • Detection level (parts per trillion): < 40
    • 2016 USEPA Health Advisory Level (parts per trillion): 70
  3. PFBS / Perfluorobutanesulfonic acid
    • Detection level (parts per trillion): < 90
    • 2016 USEPA Health Advisory Level (parts per trillion): None

 

2019-2020 PFAS Sampling

In 2019 and 2020 the County completed additional PFAS monitoring using a newer EPA testing Method. This method had lower detection levels with a minimum reporting level at 2.0 parts per trillion. The utility’s sampling consisted of quarterly sampling of our larger systems from June 2019 to February 2020.

 

While the results of the 2019-2020 sampling had some detections, the PFAS levels detected were significantly below the 2016 health advisory levels of 70 parts per trillion. The County will be performing additional PFAS sampling in 2023 as the 2019-2020 sampling showed some detections above the new 2022 EPA health advisory levels.

 

  1. South Central Water System
    • Monitoring Averages (parts per trillion)
      • PFOA: 4.0
      • PFOS: 3.4
      • PFBS: 4.4
    • 2016 EPA Health Advisory Level (parts per trillion)
      • PFOA: 70
      • PFOS: 70
      • PFBS: None
    • New 2022 EPA Health Advisory Level (parts per trillion)
      • PFOA: .004
      • PFOS: .02
      • PFBS: 2000
  2. Northwest Water System
    • Monitoring Averages (parts per trillion)
      • PFOA: 2.1
      • PFOS: 2.5
      • PFBS: 2.1
    • 2016 EPA Health Advisory Level (parts per trillion)
      • PFOA: 70
      • PFOS: 70
      • PFBS: None
    • New 2022 EPA Health Advisory Level (parts per trillion)
      • PFOA: .004
      • PFOS: .02
      • PFBS: 2000
  3. Seaboard Utilities
    • Monitoring Averages (parts per trillion)
      • PFOA: 5.5
      • PFOS: 4.0
      • PFBS: 4.6
    • 2016 EPA Health Advisory Level (parts per trillion)
      • PFOA: 70
      • PFOS: 70
      • PFBS: None
    • New 2022 EPA Health Advisory Level (parts per trillion)
      • PFOA: .004
      • PFOS: .02
      • PFBS: 2000

 

Future PFAS Sampling

EPA is developing new testing methods that measure more PFA compounds. The County will be sampling for PFAS chemicals in our larger systems starting in 2023 using the newer methods. These results will be added to our website when available.

Ask a question or reach out with a concern. We are always available to talk about how we produce and deliver your drinking water and the steps we take to maintain quality. Please contact us at (813) 246-3146.

Other Water Quality Reports