Per- and polyfluoroalkyl substances (PFAS)

Per- and Polyfluoroalkyl Substances (PFAS) are a group of over 4,000 manufactured chemicals that have been used in industry and consumer products since the 1940s because of their useful properties including their resistance to grease, oil, water, and heat. Since there are thousands of different PFAS chemicals, some of have been more widely used and studied than others. One common characteristic of concern of PFAS is that many break down very slowly and may build up in people, animals, and the environment over time.

Home-Filter Systems

There are two types of home-filter systems: point-of-use (POU) and whole house filters. Washington State Department of Health maintains a list of approved filters for Home Water Treatment  and Point-of-Use Filter Options for PFAS.

Monitoring Results

PFAS testing results for Group A drinking water systems in Washington State are available through the Washington Department of Health PFAS Testing Results Dashboard.

Drinking Water Regulations

In 2016, the Environmental Protection Agency developed Health Advisory Levels (HALs) to provide guidance until enforceable safety standards are adopted under the Safe Drinking Water Act. The HALs are health goals that help guide safety decisions when a contaminant occurs in drinking water. HALs represent an amount of each PFAS in drinking water that is almost certain not to cause harmful human health effects if consumed over a lifetime. HALs are not regulations and are not enforceable. They are based on the best available science at the time and can change as the science is updated. EPA established a HAL of 70 parts per trillion for PFOA and PFOS combined in drinking water. 

In 2021, Washington State Department of Health adopted State Action Levels (SALs) for five PFAS (PFAS State Action Level Factsheet).  This State rule requires all Group A community and non-transient and non-community public water systems to test for PFAS.  Testing is not required for Group B systems, two-party systems, or individual well owners.   If you are concerned about PFAS in your drinking water consider testing your own well or asking your water system purveyor to test the well serving your water system. The Washington Department of Health has a list of labs capable of testing for PFAS in drinking water (Accredited Labs that Test Public Drinking Water Samples for PFAS). 

In June 2022, EPA released new HALs for four PFAS in drinking water.

In July 2022, Washington State Department of Ecology concluded PFAS fall under the Model Toxics Control Act (MTCA) and issued recommended soil and groundwater cleanup levels for six of the most common PFAS compounds and released Draft Guidance for Investigating and Remediating PFAS Contamination in Washington State.

In March 2023, EPA released a proposed rule for regulating six PFAS in drinking water. The proposed rule will undergo a public review and comment process and may change before it becomes final currently anticipated to occur in late 2023 or early 2024. Washington Department of Health issued a fact sheet, providing basic information on EPA's proposal and how it relates to our state's regulation of the five PFAS in drinking water.

PFAS investigations and cleanup sites in Island County

Washington State PFAS Information

Federal PFAS Information

Other Resources