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Planning and Protection

​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​Per- and polyfluoroalkyl substances (PFAS) are a large group of chemicals that have been widely used for decades due to their ability to resist heat, oil, grease, and water. Common uses include non-stick cookware, stain-resistant carpets and fabrics, food packaging, and fire-fighting foam. These chemicals break down very slowly in the environment and can be found in water, air, soil, fish, and wildlife. They have also been identified in the blood of people across the globe. There is evidence that exposure to PFAS chemicals may have harmful health effects. Researchers and state and federal agencies continue to investigate the potential health effects, levels of PFAS in the environment, and management options. For additional information, explore the links on this page.​​

In 2019, department staff sampled finished drinking water from 81 community public drinking water treatment plants (WTP).  WTPs were selected to represent surface and groundwater sources, urban and rural land-use influence, and varying sizes of populations served. One or more PFAS were detected in 41 of the 81 WTPs. Click the link below to read the full report.​

In 2023, staff sampled finished drinking water from an additional 113 water treatment plants not included in the 2019 study. Results from that study are available at the links below.
In 2020, staff sampled 40 surface water locations across the Commonwealth.  Monitoring stations were selected to fill data gaps and represent each of the major river basins in the state.  Upstream catchment areas for these monitoring stations ranged from 0.8 to 4,288 square miles. One or more PFAS were detected at 36 of the 40 monitoring stations. Click the link below to read the full report.

In 2021, the Department for Environmental Protection (DEP) continued its efforts to evaluate potential paths of exposure to PFAS with a pilot project to test for PFAS in fish from state waters. Current scientific research indicates that certain PFAS can build up in fish over time, and consuming fish from PFAS-contaminated waters can be a route of exposure for people. Three streams from the 2020 surface water study with confirmed levels of PFAS were selected initially. Four additional streams were added in early 2022, as well as fish from a separate lake study. Fish sampled included black bass and sunfish species. 

PFAS were detected in all 98 samples from the two projects. Perfluorooctane sulfonic acid (PFOS) occurred at the highest concentrations of any PFAS. Results for PFOS ranged between 0.31 and 50 parts per billion (ppb) in fish tissue. Fifteen other PFAS were detected in at least one sample at concentrations of 18 ppb or less. The average concentration of PFOS in fish from the stream study was 13 ppb; the average for fish from the lake study was 5 ppb. 

To lower potential health risks associated with PFAS, the DEP, Department for Public Health, and Department of Fish and Wildlife Resources recommend that citizens follow existing statewide fish consumption guidance for mercury and any site-specific advisories. Recent information from the US EPA indicates that infants and young children may be particularly sensitive to some health effects associated with PFAS.  In the interim while staff collect additional data and information, sensitive populations may want to exercise additional caution when making choices on the frequency and quantity of fish consumed from state waters.

An Interim Report is available to read more. A Frequently Asked Questions document is also available. 

To learn more about current fish consumption advisories, visit the Fish Consumption Advisories webpage.​

​Additional PFAS fish tissue data are available here: PFAS Fish Tissue Data​.