PFAS are comprised of many different chemicals but the two most cited are perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA). These man-made chemicals were produced for decades in the United States for various industrial and home applications.
PFAS chemicals are commonly found in humans and throughout our environment because they are not degraded by sunlight and they are not chemically or biologically degraded in soil, air, or water.
These chemicals are also easily dissolved in water making them more likely to occur in water including groundwater wells.
Health Effects and Drinking Water Standards
Research studies have found that PFAS chemicals can cause a variety of serious health effects to both children and adults. These include various cancers and effects on the thyroid, liver, and other organs. Health effects have also been reported in fetuses and infants.
Drinking water is only one possible source of PFAS chemicals found in the human body. You can also be exposed by eating contaminated food that is exposed to PFAS while being grown or from food packaging.
Humans are also exposed to PFAS through contaminated soil or dust or from products that are made from PFAS chemicals.
Because of these health effects, PFAS chemicals have a federal Health Advisory limit of 70 parts per trillion (ppt) developed by the U.S. Environmental Protection Agency (EPA). EPA Health Advisories are not regulations and they are not enforceable for public water supplies.
Instead, they are intended to raise awareness about emerging contaminants to allow for collection of additional data on the occurrence, testing, treatment, and health effects.
In many cases, this additional research results in the creation of an enforceable drinking water standard know as a “Maximum Contaminant Level” or MCL. Some states have already begun to develop Health Advisories for some of the many chemicals that comprise PFAS.
As more research is conducted, additional drinking water standards will likely be developed. There is more information available on the federal health advisory for PFAS on the EPA drinking water health advisories PFOA and PFOS website.
Occurrence of PFAS in Pennsylvania Water Supplies
The Pennsylvania Department of Environmental Protection (DEP) recently created a website with details on PFAS and a plan to begin sampling water supplies.
In 2019, DEP began testing about 400 public water supplies that were considered at greater risk for PFAS contamination because they were located within one-half mile of potential sources of PFAS (military bases, fire training sites, old dumps or landfills, and manufacturing facilities).
Results from the initial round of testing of 96 water supplies released in late 2019 found:
-- 64 of 96 (67 percent) of water supplies had no detectable PFAS chemicals.
-- 23 of 96 (24 percent) of water supplies had detectable but very low concentrations of PFAS chemicals below 10 parts per trillion.
-- 8 of 96 (8 percent) of water supplies had low concentrations of PFAS chemicals between 10 and 30 parts per trillion.
-- Only 1 of 96 (1 percent) of water supplies had concentrations of PFAS above the EPA health advisory of 70 parts per trillion.
While these results give some indication of the occurrence of PFAS in Pennsylvania groundwater, there have not yet been any comprehensive studies of PFAS in private, household water wells or springs.
Testing Water for PFAS
If you have a private groundwater well or spring located in close proximity to high-risk activities (military bases, fire training sites, dumps, landfills, or manufacturing facilities) or if you are simply concerned about the possibility of PFAS in your water supply, you should arrange to have your water tested by a state-accredited lab.
Because PFAS chemicals are an emerging contaminant, there are currently only a few laboratories in Pennsylvania that are accredited by the DEP, but the list of available labs is expected to grow in the coming years.
The most up-to-date listing of state-accredited labs is available by visiting the search tool for accredited environmental labs on the DEP website.
In that tool, choose “perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA)” from the dropdown list of “Analytes.”
Because PFAS testing requires especially complex testing instruments and lengthy methods, it can often cost $200 to $500 for one sample. The water sample must be collected carefully using detailed instructions and special containers provided by the laboratory.
Home Treatment Systems to Remove PFAS
Research has shown that several relatively common water treatment devices are effective in removing PFAS chemicals from water.
Since the majority of PFAS exposure occurs from drinking or ingesting water, small point-of-use (POU) treatment systems that are located on one faucet can be used to avoid most PFAS exposure.
These would include reverse osmosis (RO), granular carbon filtration (GAC), or powered carbon filters.
There are also larger point-of-entry (POE) water treatment systems that can be used to treat all the water entering the home. These include anion exchange units, larger GAC filters, or whole house RO units.
The EPA recently conducted research on treatment technologies and a detailed study on POU and POE treatment systems for removing PFAS.
References and More Information
Numerous government and groundwater organizations have many educational resources on PFAS at the links below:
-- Pennsylvania Department of Environmental Protection, PFAS in Pennsylvania
-- Centers for Disease Control PFAS fact sheet
-- U.S. Environmental Protection Agency PFAS website
-- National Ground Water Association PFAS information
(Reprinted from Penn State Extension and Watershed Winds newsletter. Click Here to sign up for your own copy.
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-- August 12: Ask The Experts About Drinking Water
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