By Becky Schuerman, Domestic Water/Wastewater Extension Associate
In March of 2023, the U.S. Environmental Protection Agency (EPA) proposed new limits on six types of PFAS in drinking water. Of the thousands of PFAS in use, these six are believed to be the most prevalent in the environment: perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), perfluorononanoic acid (PFNA), hexafluoropropylene oxide dimer acid (HFPO-DA, commonly known as GenX Chemicals), perfluorohexane sulfonic acid (PFHxS) and perfluorobutane sulfonic acid (PFBS). These are known as “forever chemicals” because they do not break down in the environment or in our bodies.
PFAS can be present in our water, soil, air, food and materials in our homes. The usage of PFOA and PFOS began in the 1940s in many consumer and industrial products. The principal U.S. manufacturer of PFOS phased out its production of the chemical in the early 2000s, though PFOA and PFOS may still be present in some imported products. The Food and Drug Administration (FDA) banned both PFOA and PFOS in 2016.
Common sources historically have included fire extinguishing aqueous film-forming foam, food packaging, water and stain repellents used on carpets, upholstery, clothing and other fabrics, non-stick cookware, sealants and some industrial products. PFAS have been found to migrate into surface and groundwater.
Exposure to PFAS can come from:
• Eating fish caught in water contaminated with PFAS, specifically PFOS.
• Ingesting contaminated soil or dust.
• Eating food that was grown or raised near places where PFAS were used.
• Eating food packaged in material containing PFAS.
• Using consumer products such as stain-resistant carpeting and water or stain-repellent clothing.
• Drinking contaminated water from a municipal or private well.
Current scientific research suggests that exposure to certain PFAS compounds may lead to adverse health outcomes. Research is ongoing to determine how different levels of exposure to different PFAS can lead to a variety of health effects. On April 10, 2024, the EPA finalized the PFAS National Primary Drinking Water Regulation, setting maximum contaminant levels (MCLs) for six PFAS for Public Water Supply Systems. Both PFOA and PFOS have a legally enforceable MCL of 4 parts per trillion (ppt, also expressed as ng/L), and a health-based, non-enforceable Maximum Contaminant Level Goal (MCLG) of 0 in public drinking water. In addition, a Hazard Index of below 1 is required for four other PFAS compounds, as described at https://go.unl.edu/epa_substances.
HEALTH EFFECTS
Ongoing research continues to study the potential health effects of exposure to PFAS. According to the EPA, current peer-reviewed scientific studies have shown that exposure to certain levels of PFAS may lead to:
• Reproductive effects such as decreased fertility or increased high blood pressure in pregnant women.
• Developmental effects or delays in children, including low birth weight, accelerated puberty, bone variations or behavioral changes.
• Increased risk of some cancers, including prostate, kidney and testicular cancers.
• Reduced ability of the body’s immune system to fight infections, including reduced vaccine response.
• Interference with the body’s natural hormones.
• Increased cholesterol levels and/or risk of obesity.
OCCURRENCE OF PFAS IN NEBRASKA’S WATERS
In 2013–2015, selected public water supply systems in Nebraska were tested for several PFAS compounds, and no PFAS were found (screening level was 70 ppt for that project). The Nebraska Department of Environment and Energy (NDEE) has a voluntary water-monitoring project for the screening of PFAS compounds for community water systems fewer than 3,300 in population. Some samples have exceeded the proposed PFOA and PFOS MCL. As with any other monitored contaminant, when an exceedance occurs, follow-up testing is performed. It is anticipated that domestic water wells are at risk of containing PFAS above the MCL if they are down gradient of, or near, a source of PFAS.
If a domestic well is near a community water supply well, the public can contact that community water system to obtain the results of any PFAS water quality testing. If a Nebraska community water system (fewer than 3,300 in population) has not yet been tested, encourage the community water system to communicate with NDEE to participate in the voluntary PFAS monitoring project.
Multiple environmental groups have compiled interactive maps that are updated as new PFAS information becomes available. One such map is available by the Environmental Working Group and can be found at https://go.unl.edu/pfas_map. Note that the data from many public water supply systems has yet to be published on these websites but may be obtained by calling community water systems.
HOME WATER TESTING OPTIONS
For homeowners considering testing to evaluate PFAS in their drinking water, EPA recommends using an accredited laboratory to test water samples and to use an EPA testing method. There are few such labs in our region. One is Pace Analytical Laboratory Services, which recommends ordering the 537.1 sample kit if you want to have a private water tested for PFAS. To order a kit, email Pace Labs at PFAScitizen@pacelabs.com. Testing for PFAS is expensive, and the 537.1 test will cost over $500.
Homeowners near groundwater sources known to be contaminated by PFAS may choose to invest in a water treatment system instead of water quality testing.
HOME WATER TREATMENT OPTIONS
Homeowners with PFAS in a water source above the proposed MCL, or who are concerned about their water quality and want to minimize their risk of exposure through drinking, can apply one of the following technologies to treat their water. Recent projects conducted by the EPA and the Water Quality Research Foundation each identified that reverse osmosis (RO) and activated carbon filters in point-of-use (POU) devices can be effective at removing PFAS chemicals. A POU device treats what is in the house at a specific location, such as a kitchen sink.
The effectiveness of residential treatment units at removing PFAS from water has shown to be impacted by water quality conditions, concentration levels of PFAS in the water and operational conditions of the treatment units. When purchasing a home POU device to remove PFAS, look for evidence on the packaging that the device has met the National Science Foundation/American National Standards Institute 53 or 58 standards. These require independent testing and certification that the device can remove the two most common PFAS chemicals. A list of POU devices that currently have met these standards and are anticipated to remove PFAS can be found at https://go.unl.edu/pfoa-pfos-water.
Homeowners should be careful to follow the POU device manufacturer’s instructions for system maintenance and replacement of cartridges.
Certain ion exchange resin systems have been found to be effective for removing PFAS at the municipal level, but most home ion exchange treatment systems have not been designed to be effective for PFAS removal. For example, ion exchange systems for water softening are not designed to remove PFAS. Ion exchange systems for home treatment have not been independently proven to be effective. Boiling water that contains PFAS will actually concentrate the contaminant.
Recommendations for treatment methods may change in the future if additional PFAS compounds are found to become common in drinking water sources.