Both substances belong to a group of industrial, human-made chemicals known as PFAS, or Per- and polyfluoroalkyl substances (PFAS). These chemicals have been manufactured in the US since the 1940s, although US companies began phasing out PFOA and its related chemicals and emissions in 2006. PFOA (perfluorooctanoic acid) and PFOS (perfluorooctane sulfonate) are still produced internationally, and can legally be imported into the United States via consumer goods. Other less studied PFAS are still in use.
Officials and residents in Parchment are concerned because studies have linked the chemicals to reproductive and developmental issues, along with liver, kidney, and immunological effects. Other concerns include high cholesterol, obesity, thyroid hormone disruption, and cancer.
Although the source of the Michigan contamination hasn’t yet been identified, an EPA fact sheet on the chemical group notes that the high levels of PFAS necessary to contaminate drinking water are usually associated with local industry. Oil refineries, manufacturers, and airfields where PFAS were used in firefighting are often possible sources.
According to MLive, the Department of Environmental Quality tested three groundwater wells that usually serve Parchment and a nearby township. They found PFAS levels ranging from 279 to 2,150 parts per trillion. The EPA recommends a lifetime exposure of 70 parts per trillion in total for both PFOS and PFOA.
PFAS: A Growing Concern
Over the last ten years, scientists have taken a growing interest in PFAS and the chemical group’s possible effects. The Agency for Toxic Substances and Disease Registry (a division of the US Department of Health and Human Services) launched studies with state partners to determine how the chemicals might be affecting people exposed through contaminated drinking water.
Another study, known as the C8 Study, analyzed 69,000 people living in areas where drinking water contamination caused elevated PFOA in blood levels by more than 500% over a representative sample. The study found probable links between the elevated blood levels and the following conditions: high cholesterol, ulcerative colitis, thyroid function, testicular cancer, kidney cancer, preeclampsia, and elevated blood pressure during pregnancy.
The EPA has classified PFAS as an emerging threat and a possible carcinogen, and mandated national testing of municipal water for PFAS between 2013 and 2015. Communities whose water supplies exceeded EPA health advisory limits were publicly identified and measures taken to rid the water of the chemicals. Scientists in some circles claim the EPA limits are too high, and some states—such as New Jersey—are setting their limits for PFAS chemicals lower than EPA standards. The Environmental Working Group estimates more than 1500 communities have water contaminated with PFAS.
Beyond Drinking Water: Where Else Can You Find PFAS?
In addition to contaminated drinking water, PFAS can be present in low levels in food. Food contamination occurs due to contaminated soil or irrigation water, PFAS-treated packaging, and PFAS-containing processing equipment. PFAS are also used in a variety of products related to the aerospace, automotive, and construction industries. They may also be present in the following products:
- Non-stick cookware (e.g. Teflon)
- Stain-resistant sofas and carpets
- Water-resistant clothing and mattresses
- Food packaging (PFAS has been phased out of most food packaging)
- Paint and sealants
- Cleaning products
- Waxes and polishes
- Fire-fighting foam and other materials
- Animal food products (e.g. fish and shellfish)
Additionally, because children spend a lot of time on hands-and-knees, they may transfer the chemicals into their mouths from stain resistant upholstery, carpets, and carpet cleaners. People can also breathe in air contaminated with PFAS from soil, dust, carpets, upholstery, and fabric sprays.
How to Reduce PFAS Exposure
Efforts to lower our exposure to PFAS are already underway and having an impact. Thanks to a global stewardship program to phase out production of PFOA and PFOS by 2015, you’re unlikely to encounter these chemicals in food packaging today. Analysis conducted through the National Health and Nutrition Examination Survey indicates that levels of these PFAS are declining among the general population thanks to these phase-outs.
Unfortunately, other sources of PFAS exposure have been harder to control due to the chemicals’ staying power. PFAS are very persistent and remain in the human body for 2-9 years depending on the particular chemical. They are also persistent in the environment and don’t break down in soil or water. That means exposure can continue wherever these chemicals are present whether or not they are actively being used or manufactured.
If you’re concerned about PFAS, consider limiting your exposure in the following ways:
- Make healthy cookware choices. Avoid non-stick coatings.
- Avoid eating fish where exposure may occur. Check with your local or state authorities for health advisories regarding fresh-caught fish.
- Avoid buying water-repelling or stain-resistant fabric sprays that may contain PFAS. While wearing chemical-containing clothes isn’t likely to harm you (since PFAS are not readily absorbed through the skin), manufacturing these products often exposes the environment to PFAS-related chemicals. If you’re unsure about any product and its safety, talk to the Consumer Product Safety Commission at (800) 638-2772.
- If you live in an area where PFAS may have been used by industry, have your drinking water tested by a certified lab. You can also use the contaminated sites tracker from Northeastern University’s Social Science Environmental Health Research Institute to find out more about locations affected by PFAS contamination. The Environmental Working Group also maintains a map of sites affected by PFAS.
Filtering Out PFAS: Home Water Treatments
If your drinking water is above the EPA health advisory limit of 70 parts per trillion, use an alternative source for any water that may be ingested, such as when brushing teeth, cooking, or drinking. Keep on top of local health advisories as they evolve.
If you’re concerned about PFAS exposure but don’t live in one of the locations identified as contaminated, home water treatment can bring peace of mind. Analysis from the American Waterworks Association shows that a home water filter containing the following components can be effective at reducing PFAS exposure:
- Granulated activated carbon (GAC) or powdered activated carbon (PAC) filter (reduced PFOA and PFOS by 90% or more).
- Reverse osmosis (with a semi-permeable membrane) filtration system (reduced both chemicals by 90% or more).
- Nanofiltration system with pore sizes at 0.001 micron (reduced both chemicals by 90% or more).
- Anion exchange systems are effective at removing PFOS (90% or more depending on polymer matrix and porosity) but less effective at removing PFOA (10-90%) and other PFAS.
Often systems combining the above technology work the best. Tests conducted by a third party laboratory for Big Berkey Water Filters show that their countertop water filtration system reduced contamination of PFOA by 99.9%.
You can also prepare for a temporary loss of water by including water and water treatment options in your emergency storage. This includes storing municipal or rainwater in food-grade containers or purchasing a portable emergency filter or purification device.
For more information:
- An Overview of Perfluoroalkyl and Polyfluoroalkyl Substances and Interim Guidance for Clinicians Responding to Patient Exposure Concerns, May 2018. Agency for Toxic Substances and Disease Registry, National Center for Environmental Health.
- Fact Sheet: 2010/2015 PFOA Stewardship Program. Environmental Protection Agency.
- Per- and Polyfluoroalkyl Substances (PFAS) and Your Health. Agency for Toxic Substances and Disease Registry.