PFAS are used in manufacturing processes, so they are not present at high concentrations in most consumer products. However, when they are not properly disposed of, PFAS can reach sources of drinking water, be present in dust and accumulate in fish and other animals that we consume. Some PFAS uses such as in insecticides, carpet treatments and firefighting foams can lead to additional exposures.

Aqueous film-forming foams (AFFFs)
AFFFs have been used at military bases, airports, and firefighting training sites to suppress flammable liquid fires, and several PFAS compounds have been ingredients in these products. Uncontained AFFF runoff has migrated through soil to contaminate nearby aquifers and surface waters at a number of sites in the United States.

Manufacturing
Facilities that produced PFAS products or used PFAS in manufacturing processes have released the chemicals through wastewaters, solid waste, and air emissions.

Landfill disposal
At several historic landfill sites, PFAS-contaminated waste has contributed to leachate—liquid that has passed through a landfill and extracted dissolved and suspended matter from it—that subsequently contaminated natural waters. Today, untreated landfill leachate may pose a contamination risk.

Environmental risks usually depend on the concentration of the PFAS contaminant and on exposure conditions. Individuals exposed to large amounts of PFAS in the air have been found to suffer negative health effects. If ingested above certain levels, various PFAS can cause problems in the liver, kidneys and nervous system and may also create developmental and reproductive issues.

PFAS were included in the EPA’s Third Unregulated Contaminant Monitoring Rule testing in order to determine how prevalent certain perfluorinated compounds are in U.S. drinking water supplies and at what level they appear.

Following that testing, in May 2016, the EPA released health advisories for perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), making a lifetime health advisory for each compound, or a sum total of the two, of 0.07 parts per billion.

Under the recent round of UCMR3 testing, many water systems nationwide tested for PFAS. Contact your public water system to learn more about PFAS testing and results. You can usually find contact information for your public water system on your water bill.

To date, there are three widely applied technologies for PFAS reduction once water is contaminated. Each has advantages and limitations. All three generate waste streams that themselves must be managed. All require significant increases in capital and operating expenses. They include:

• Activated carbon, in which contaminants are adsorbed by the activated carbon media. The media needs to be regenerated periodically to renew absorptive capabilities.
• Anion exchange, typically called ion exchange. The ion exchange process removes contaminants, such as PFAS, from water by exchanging them for another charged substance–typically chloride–on the surface of a resin. Removal rates vary by PFAS compound.
• Membrane filtration, using nanofiltration and/or reverse osmosis (RO) membranes. The technology removes dissolved substances by passage through a porous membrane at high pressure.

PFAS in drinking water are not currently regulated in the United States, however six perfluorinated compounds were monitored under EPA’s Third Unregulated Contaminant Monitoring Rule. The PFAS monitored under UCMR3 included: PFOS, PFOA, perfluorononanoic acid (PFNA), perfluorohexanesulfonic acid (PFHxS), perfluoroheptanoic acid (PFHpA) and perfluorobutanesulfonic acid (PFBS).

Following the UCMR3 testing, in May 2016, the EPA released health advisories for perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), making a lifetime health advisory for each compound, or a sum total of the two, of 0.07 parts per billion. In February 2020, the EPA proposed regulatory determinations for PFOS and PFOA in drinking water.

The EPA has been examining both potential health risks and the UCMR3 occurrence data when determining if these compounds should be regulated. Their decision on whether or not to regulate is based in large part on whether the UCMR3 testing shows a significant number of U.S. drinking water systems have concentrations of PFAS at levels of concern.

Following the UCMR3 testing, in May 2016, the EPA released health advisories for PFOA and PFOS, making a lifetime health advisory for each compound, or a sum total of the two, of 0.07 parts per billion.

If you get your drinking water from a private well, you should have your water tested by a certified laboratory regularly. PFAS are not contaminants typically measured; if you want to know if PFAS are present in your well water you may contact one of the labs on the UCMR3 laboratory list for information on how to sample and where to send samples for analysis. Additional information about well water testing from EPA is available on its private drinking water well FAQ page.

Bottled water quality can vary. Bottled water in the United States is regulated by the U.S. Food and Drug Administration and is required to meet standards equal to the EPA’s tap water standards. There are also individual state standards. However, in most cases, you must contact the bottled water manufacturer for information about contaminant levels.