How PFAS Got into Our Bodies: A Short History
Welcome to the third issue of ContamiNation. Subscribe for free to receive it monthly, and please share this newsletter with others.
No one set out to create indestructible chemicals, the stuff of horror films. Accidents and opportunism on the part of chemical manufacturers led to the spread of per- and polyfluoroalkyl substances (PFAS), aided by the U.S. government’s long-standing failure to regulate toxic chemicals.
The first known PFAS, a white powder given the name polytetrafluoroethylene (PTFE), formed inadvertently in 1938 from gas stored in a canister at a DuPont company lab. Upon further testing, it proved capable of reducing friction and resisting heat, inspiring DuPont to develop Teflon coatings.
During World War II, the chains of tightly bonded carbon and fluorine that characterize PFAS proved useful in the Manhattan Project. And in post-war years, these synthetic compounds became part of a plastics manufacturing boom. In 1948, DuPont opened a new plant in Parkersburg, West Virginia, to manufacture Teflon resin, nylons and other petrochemical products.
That plant was among the first places where the extent of PFAS pollution came to light half a century later (a story captured in the films “Dark Waters” and “The Devil We Know”).
3M first released its Scotchgard product, incorporating PFAS, in 1956, several years after a laboratory accident in which researchers noticed that an experimental liquid spilled on shoes resisted cleanup, causing water to bead up.
In subsequent decades, industrial and commercial applications of PFAS exploded. Researchers in a 2020 study estimated that more than1,400 PFAS compounds are used in 200-plus product categories. A partial list includes plastics, building materials (like wiring, metal roof coatings, sealants and flooring materials), solar panels, textiles, electronics, photography, insecticides, paints, ammunition, artificial turf, personal care products, topical flea and tick formulations for pets, food packaging, automotive and aeronautic uses, and some firefighting foams.
The first indications that these compounds had found their way into human blood came in a 1968 study published by a dental researcher at the University of Rochester, Donald Taves. In 1975, he and his team reported a form of fluorine in more than 100 blood samples that could not be traced to water fluoridation. The fluorine occurred in nearly all the blood samples tested, tightly bound to the albumin (protein) and so unlikely to be readily excreted.
One of the researchers contacted 3M to inquire whether the fluorinated compounds it and DuPont produced might be the source. Following the call, a staff scientist reported to colleagues “We plead ignorance.” (Journalist Sharon Lerner provides a detailed account of what 3M knew and covered up.)
When the Toxic Substances Control Act (TSCA) was enacted one year later, roughly 60,000 chemicals—including all the PFAS developed to date—were grandfathered into the legislation. Chemical production boomed and more than two decades passed before the Environmental Protection Agency (EPA) persuaded U.S. manufacturers to phase out production of two of the most common and well-studied PFAS.
Manufacturers turned to new PFAS formulations, few of which have been studied. Nearly 50 years after passage of the TSCA, PFAS now number more than 14,000 and production continues unabated.
Research: PFAS Blood-testing Options and Limitations
Testing for PFAS in blood is an essential part of understanding individual and community exposure, but it’s not always accessible to those who need it. Conventional blood serum tests require a doctor’s orders, a phlebotomist to administer, and shipment of samples on dry ice back to a laboratory. The price can run up to $600, factoring in the blood draw, a cost not covered by some insurance plans (or for underinsured individuals with high deductibles).
Now there’s a more affordable option—a finger-prick test self-administered at home—that researchers at Michigan State University (MSU) helped validate last year. While enrolling a cohort of highly exposed people in a study that involved blood serum tests, MSU staff offered participants the chance to add on a supervised finger-prick test.
The new tests, which use tiny amounts of whole blood, appear to capture “legacy” (eight-carbon) PFAS as accurately as tests involving blood serum (formed after clotting and removal of plasma and blood cells). In fact, says Courtney Carignan, an environmental epidemiologist at MSU, “we saw a PFAS (the compound PFOSA) that was not in the serum,” which raises questions about how many compounds aren’t captured in standard blood testing.
Carignan thinks that many PFAS escape detection, particularly newer and less studied formulations that involve short-chain compounds (like the six-carbon “GenX” chemicals) and ultrashort-chain compounds, with one to three carbons. “I’m not confident that the traditional biomonitoring tests, including the finger-prick tests, are the appropriate means for assessing current-use PFAS,” she says.
A recent study at Emory University lends support to the idea that many newer PFAS formulations are flying below the radar. When researchers analyzed blood serum for 47 PFAS, deliberately including numerous ultrashort-chain and short-chain compounds and precursors, they discovered that the 9 ultrashort- and short-chain compounds found were predominant in all the serum samples (as well as in the household dust and drinking water they sampled). Those newer PFAS formulations constituted on average 69 to 100 percent of the total PFAS concentrations.
Currently, both serum and finger-prick blood tests primarily capture “legacy” PFAS compounds. The new finger-prick test, developed by Eurofins and validated by MSU, comes in two versions. One that assesses 16 “legacy” PFAS compounds (those that the CDC tests for in its national blood survey) is available for $249 through a Eurofins subsidiary. The second test, analyzing 45 PFAS, can be ordered directly through Eurofins.
Whole blood results require a conversion factor to match what a serum test would deliver (generally about two times the amount but follow test instructions).
Carignan and other PFAS researchers have compiled a wealth of objective information on blood testing options and guidance for interpreting results at the PFAS Exchange website.
News of Note
Matt Simon, author of A Poison Like No Other, writes in Wired magazine of how hurricanes now deliver—in their torrential downpours—boatloads of microplastics gathered from seawater and from oceanic garbage patches. He reports on research that found more than 100,000 microplastics per square meter fell in Newfoundland during Hurricane Larry’s peak in 2021. (And only larger microplastics were included.) The same dynamic is at work with lesser winds, Simon writes: “…the seas are in fact burping the particles into the atmosphere to blow back onto land, both when waves break and when bubbles rise to the surface, flinging microplastics into sea breezes.”
A study done by Ocean Conservancy and University of Toronto researchers demonstrated the prevalence of microplastics in commonly eaten protein purchased in the U.S. (including seafood, meat and plant-based proteins). Highly processed products were the most concentrated source.
If you’ve been wondering why ContamiNation cites “nanoplastics” (the tiniest of plastic shards and fibers), as distinct from the larger microplastics, an overview in Vice by Mirjam Guesgen helps illuminate their particular threats. Nanoplastics are less well understood because they require specialized equipment, rather than microscopes, to detect. They can also be more reactive. “Smaller pieces means more surface area,” she writes, “which means more space for chemical components of plastic to leak out or react with other compounds in the environment” (like PFAS, which seem to have a particular affinity according to one researcher interviewed). Human health impacts of nanoplastics are unknown, with the limited research to date primarily on small filter-feeders, Guesgen writes: “We know very little about what nanoplastics do inside animals higher up the food chain, let alone in humans.”
A new study by researchers at Columbia and Rutgers universities found between 110,000 and 400,000 nanoplastic particles per liter of bottled water, after testing three common brands, AP reports. A response from the International Bottled Water Association was not reassuring: “Bottled water is just one of thousands of food and beverage products packaged in plastic containers,” the Association wrote in a statement to The Hill.
The complex interaction between marine microorganisms and microplastics explored in recent work at the University of New Hampshire, reported in EOS. Scientists are concerned that microplastics may be disrupting oceans’ carbon cycling (potentially reducing its capacity to absorb carbon dioxide).
PFAS are associated with a variety of adult-onset cancers, but a new study of a Finnish maternity cohort (whose blood was sampled in the first trimester) provides evidence that some compounds may also be linked to acute lymphoblastic leukemia, the most common childhood cancer globally. And in laboratory research at Yale University, two commonly found PFAS compounds (PFOA and PFOS) prompted cancer cells to migrate to new positions, an indicator that they may play a role in cancer metastasis.
The close ties between PFAS and plastics are underscored in a new study on the high disease burden and economic costs linked to endocrine-disrupting chemicals in plastics. The estimated total for plastic-related disease burden in four categories of chemicals was $249 billion just in 2018. Swedish ecotoxicologist Bethanie Carney Almroth, interviewed for a CNN story on the study, describes our reliance on plastic products with unknown chemicals, undetermined exposures and unstudied health consequences as “absolutely insane.”
Good Resources
The Environmental Working Group (EWG) has a “Skin Deep” database to help you identify hazards lurking in personal care products. If you think the Food and Drug Administration has that covered, a look at its website may change your mind. Other resources to help you locate non-toxic products include EWG’s Healthy Living App, Silent Spring Institute’s Detox Me app, and Clearya (available as an app or through certain browsers).
Good Riddance
If you’re doing research on personal care products, consider how many nanoplastics may leach from plastic containers (see the recent Columbia study cited above). It’s getting easier to avoid plastic in this realm with products like shampoo and conditioner bars and dental floss packaged in cardboard or glass (and not coated with PFAS). To find local plastic-free options, visit food co-ops or “refill” stores.
Thanks for reading!
So, how can PFAS be removed from the body, once there? I’ve read a study of ex vivo experiments, for example, where DMSO is used to break down these molecules, except with some containing certain sulfur based radicals. But these have to be heated to about 210F to get results.