PFAS ‘forever chemicals’ tied to cancer, birth defects

Per- and Polyfluoroalkyl Substances (PFAS) are a group of thousands of manufactured chemicals widely used by a range of industries and commonly found in a large number of consumer products. One common characteristic of PFAS is that they persist in the environment and can accumulate in humans and animals. For this reason, they are often referred to as “forever chemicals.”

Some PFAS have been linked to cancer, birth defects, liver disease, thyroid disease, decreased immunity, hormone disruption and a range of other serious health problems.

Most people in the United States have been exposed to some PFAS, according to the U.S. Centers for Disease Control and Prevention (CDC). The chemicals have been documented in the blood of people and animals around the world, and have been found to be pervasive in the environment, particularly in areas where manufacturers or other industrial users are actively handling PFAS. In response to a Freedom of Information Act request, the U.S. Environmental Protection Agency (EPA) in 2021 released a spreadsheet of more than 120,000 facilities around the U.S. that may be handling PFAS. Download that spreadsheet here.

Researchers have identified the following routes of exposure to PFAS:

Drinking water – in public drinking water or tap water systems and private drinking water wells.
Soil and water at or near waste sites – at landfills, disposal sites, and hazardous waste sites.
Firefighting foam – used in training and emergency response events at airports, shipyards, military bases, firefighting training facilities, chemical plants, and refineries.
Manufacturing or chemical production facilities that produce or use PFAS – oil and gas drilling sites, chrome plating, electronics, and certain textile and paper manufacturers.
Food – fish caught from water contaminated by PFAS and dairy products from livestock exposed to PFAS, and other foods.
Food packaging – grease-resistant paper, fast food containers/wrappers, microwave popcorn bags, pizza boxes, and candy wrappers.
Household products – stain and water-repellent used on carpets, upholstery, clothing, and other fabrics; cleaning products; non-stick cookware; paints, varnishes, and sealants.
Personal care products – shampoos, dental floss, and cosmetics.

PFAS chemicals are hard to avoid, but experts say there are ways to reduce exposure. For tips, see this Washington Post article, How can I avoid eating food with ‘forever’ chemicals?

Companies knew PFAS was “highly toxic”

Though PFAS have been commercially produced since the 1940s, their toxicity was not publicly established until the late 1990s. By then, manufacturers had already known for decades that PFAS are toxic and ubiquitous.

In a May 2024 article for The New Yorker and ProPublica, Sharon Lerner reports that 3M scientists discovered PFOS was present in human blood as early as the 1970s. They also had evidence from animal studies that PFOS was highly toxic. Yet they continued to produce millions of pounds of the compound every year.

How 3M Discovered, Then Concealed, the Dangers of Forever Chemicals. The company found its own toxic compounds in human blood—and kept selling them. By Sharon Lerner, The New Yorker (5.20.24)
Nine Takeaways From Our Investigation Into 3M’s Forever Chemicals: What you need to know about the inside story of how the company allowed PFOS to seep into all of us while sitting on research that showed the chemical is toxic. ProPublica

A 2023 review paper in the Annals of Global Health, based on previously secret industry documents archived at the UCSF Chemical Industry Documents Library, examines strategies of corporate manipulation of science used by manufacturers of PFAS. The review shows that companies knew that “PFAS was ‘highly toxic when inhaled and moderately toxic when ingested’ by 1970 — forty years before the public health community.”

The research establishes that “the industry used several strategies that have been shown common to tobacco, pharmaceutical and other industries to influence science and regulation – most notably, suppressing unfavorable research and distorting public discourse.” See CBC article, Industry knew about risks of PFAS ‘forever chemicals’ for decades before push to restrict them.

Long history of warnings about health risks of PFAS

Environmental and human health experts and advocates have long been critical of the EPA for a lack of research into, and regulation of, PFAS. Researchers, lawyers and environmental and human health advocates have warned about the dangers of PFAS for roughly 20 years, and evidence has come to light showing that companies involved in manufacturing PFAS have known even longer about dangers to human health.

Research has demonstrated that two types of PFAS, Perfluorooctanoic Acid (PFOA) and Perfluorooctane Sulfonate (PFOS), are very harmful to humans and animals. In 2016, the National Toxicology Program (NTP) concluded that PFOA and PFOS were a specific hazard to immune system function in humans. U.S. manufacturers have been replacing those types of PFAS with other types, though concerns persist about the replacements.

On Nov. 16, 2021, the EPA said it was sending four “draft documents” to its Scientific Advisory Board that contain new data and analyses. The new information indicates that “negative health effects may occur at much lower levels of exposure to PFOA and PFOS than previously understood and that PFOA is a likely carcinogen,” according to the EPA.

PFOA, also known as C8, was a key ingredient in non-stick Teflon products. C8 was originally manufactured by 3M and then by DuPont until the health hazards of the chemical were made public through a class-action lawsuit. A replacement chemical called GenX was introduced by DuPont in 2009 as a safer alternative to PFOA, but an investigation by The Intercept found that DuPont filed 16 reports with the EPA citing numerous harmful health effects of the chemical on animals, sparking concerns about the safety of the substitute.

A C8 science panel was formed as part of the settlement of a class-action lawsuit approved in February 2005 by West Virginia Circuit Court. That case involved allegations that human health problems were caused by releases of C8 from a DuPont facility in West Virginia. The science panel was charged with conducting a community study to help evaluate potential links between C8 exposure and any human disease. The research findings are detailed here. The litigation and settlement were largely the work of U.S. lawyer Robert Bilott.

Bilott has spent the last two decades advocating for strict PFAS regulation and corporate accountability for PFAS pollution. His investigation into PFAS, including the corporate efforts to cover up harm, has been documented in a book, a feature film and a documentary film, among other works.

EPA roadmap to restrict PFAS

In 2018, the U.S. Centers for Disease Control and Prevention (CDC) published a 852-page review of PFAS health dangers, challenging the EPA’s determination of what the regulator considered safe levels for some of the compounds, finding that exposures could be a threat at many times lower than what the EPA had established.

In October 2021, the EPA released what it described as a “strategic roadmap” aimed at restricting PFAS from being released into the environment. The plan also is supposed to accelerate the cleanup of existing PFAS contamination. The EPA said highlights of its plan include:

“Aggressive” timelines to set enforceable drinking water limits under the Safe Drinking Water Act “to ensure water is safe to drink in every community”.
Timelines for actions involved in the establishment of “effluent guideline limitations”, for nine industrial categories.
Establishment of a hazardous substance designation under the federal Superfund law that enhances the government’s ability to hold PFAS polluters financially accountable.
A review of past actions on PFAS taken under the Toxic Substances Control Act (TSCA) to address those that are insufficient.
Increased monitoring, data collection and research so that the agency can identify what actions are needed and when to take them.
A final toxicity assessment for a type of PFAS called GenX used in manufacturing nonstick coatings that has been found in drinking water, rainwater and air samples.
Continued efforts to address PFAS emissions into the air.

In June 2022, EPA announced a new drinking water health advisories for PFAS chemicals and $1 billion in funding to strengthen health protections. (EPA press release) (Washington Post)

In March 2023, EPA proposed proposed the first national drinking water standard for PFAS, which could affect affect drinking water for nearly everyone in the United States. (CNN)

The EPA has also been pursuing research into “PFAS destruction technology” and other possible mitigation measures amid mounting evidence of the pervasiveness of the PFAS compounds.

States move to restrict PFAS

More than 100 laws have been enacted in 24 states to ban or restrict the use of PFAS chemicals used for waterproof, stain-repellent, nonstick or fire-resistant properties in a wide array of everyday household products. So far in 2023, 195 new bills were introduced in dozens of state legislatures, seeking to require that an expanding list of products be PFAS-free.See Washington Post article, States take matters into their own hands to ban ‘forever chemicals’ (6.5.23)

Statements on PFAS

Zürich Statement on Future Actions on Per- and Polyfluoroalkyl Substances (PFASs), Environmental Health Perspectives, August 2018.

Comment on “Fluorotechnology Is Critical to Modern Life: The FluoroCouncil Counterpoint to the Madrid Statement,” Environmental Health Perspectives, July 2015.

The Madrid Statement on Poly- and Perfluoroalkyl Substances (PFASs), Environmental Health Perspectives, May 2015.

Helsingør statement on poly- and perfluorinated alkyl substances (PFASs), Chemosphere, November 2014.

Research

Immune function

Mixtures of PFAS reduce the in vitro activation of human T cells and basophil, Chemosphere, September 2023. See also press release from the Helmholtz Centre for Environmental Research, and coverage in Yahoo News.

Inflammatory bowel disease

Inflammatory bowel disease and biomarkers of gut inflammation and permeability in a community with high exposure to perfluoroalkyl substances through drinking water, Environmental Research, November 2019.

Kidney Function

Perfluorooctanoic acid and chronic kidney disease: Longitudinal analysis of a Mid-Ohio Valley community, Environmental Research, April 2016.

Exposure to perfluoroalkyl acids and markers of kidney function among children and adolescents living near a chemical plant, Environmental Health Perspectives, May 2013.

Liver Function

Modeled Perfluorooctanoic Acid (PFOA) Exposure and Liver Function in a Mid-Ohio Valley Community, Environmental Health Perspectives, August 2016.

Neuropsychological Outcomes

Perfluorooctanoate and neuropsychological outcomes in children, Epidemiology, July 2013.

Obesity

In uteroexposure to perfluoroalkyl substances and early childhood BMI trajectories: A mediation analysis with neonatal metabolic profiles, Science of the Total Environment, April 2023.

Early life perfluorooctanoic acid (PFOA) exposure and overweight and obesity risk in adulthood in a community with elevated exposure, Environmental Research, July 2014.

Pregnancy

Impact of exposure uncertainty on the association between perfluorooctanoate and preeclampsia in the C8 Health Project population, Environmental Health Perspectives, January 2016.

Perfluorooctanoic Acid exposure and pregnancy outcome in a highly exposed community, Epidemiology, May 2012.

Relationship of Perfluorooctanoic Acid Exposure to Pregnancy Outcome Based on Birth Records in the Mid-Ohio Valley, Environmental Health Perspectives, March 2012.

Serum Perfluorooctanoic Acid and Perfluorooctane Sulfonate Concentrations in Relation to Birth Outcomes in the Mid-Ohio Valley, 2005-2010, Environmental Health Perspectives, October 2013

PFOA and PFOS serum levels and miscarriage risk, Epidemiology, July 2014.

Puberty

Association of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) with age of puberty among children living near a chemical plant, Environment Science & Technology, October 2011.

Sperm / reproductive impacts

Maternal Exposure to Per- and Polyfluoroalkyl Substances (PFAS) and Male Reproductive Function in Young Adulthood: Combined Exposure to Seven PFAS, Environmental Health Perspectives, October 2022.

Thyroid

Metabolic Signatures of Youth Exposure to Mixtures of Per- and Polyfluoroalkyl Substances: A Multi-Cohort Study, Environmental Health Perspectives, February 2023.

High exposure to perfluorinated compounds in drinking water and thyroid disease. A cohort study from Ronneby, Sweden. Environmental Research, September 2019.

Exposure to perfluoroalkyl substances and thyroid function in pregnant women and children: A systematic review of epidemiologic studies, Environment International, February 2017.

Perfluorooctanoic acid exposure and thyroid disease in community and worker cohorts,:Epidemiology, March 2014.

Thyroid Function and Perfluoroalkyl Acids in Children Living Near a Chemical Plant, Environmental Health Perspectives, March 2012.

Ulcerative colitis

PFOA and ulcerative colitis, Environmental Research, May 2018.

Ulcerative colitis and perfluorooctanoic acid (PFOA) in a highly exposed population of community residents and workers in the Mid-Ohio Valley,:Environmental Health Perspectives, August 2013.

Exposure, water contamination issues, general

Estimated Transfer of Perfluoroalkyl Substances (PFAS) from Maternal Serum to Breast Milk in Women Highly Exposed from Contaminated Drinking Water: A Study in the Ronneby Mother–Child Cohort, Science of the Total Environment, May 2023.

PFASchemicals were detected in every umbilical cord blood sample across 40 studies conducted over the last five years, according to a review of scientific literature conducted by the Environmental Working Group. November 2022. (See coverage in The Guardian.)

Revisiting pesticide pollution: The case of fluorinated pesticides, Environmental Pollution, January 2022.

Evaluation and management strategies for per- and polyfluoroalkyl substances (PFASs) in drinking water aquifers: perspectives from impacted U.S. northeast communities,:Environmental Health Perspectives, June 2018.

Half-lives of PFOS, PFHxS and PFOA after end of exposure to contaminated drinking water, Occupational and Environmental Medicine, November 2017.

Technical Report: Half-lives of PFOS, PFHxS and PFOA after end of exposure to contaminated drinking water, The Sahlgrenska Academy Institute Of Medicine, University of Gothenburg, 2017.

A cohort incidence study of workers exposed to perfluorooctanoic acid (PFOA),:Occupational Environmental Medicine, May 2015.

Associations Between Serum Perfluoroalkyl Acids and LINE-1 DNA Methylation, Environment International, February 2014.

Cohort mortality study of workers exposed to perfluorooctanoic acid, American Journal of Epidemiology, November 2012.

Environmental fate and transport modeling for perfluorooctanoic acid emitted from the Washington Works Facility in West Virginia, Environment Science & Technology, January 2011.

Private drinking water wells as a source of exposure to PFOA in communities surrounding a fluoropolymer production facility, Environmental Health Perspectives, January 2011.

Biomarker-based calibration of retrospective exposure predictions of perfluorooctanoic acid, Environmental Science & Technology, May 2014.

Accumulation and clearance of PFOA in current and former residents of an exposed community, Environmental Health Perspectives, January 2011.

Epidemiologic evidence on the health effects of perfluorooctanoic acid (PFOA), Environmental Health Perspectives, August 2010.

The C8 Health Project: Design, methods, and participants, Environmental Health Perspectives, December 2009.

News & opinion

Child growth and development hampered by PFAS in blood, study says, by Sandee LaMotte, CNN, March 20, 2023.

Pesticides Are Spreading Toxic ‘Forever Chemicals,’ Scientists Warn: Common chemicals sprayed on many crops each year are cloaked in bureaucratic uncertainties, by Meg Wilcox, Scientific American June 15, 2022. “And now researchers are warning of yet another—and so far under recognized—source of these troubling toxins: common pesticides.”

EPA warns toxic ‘forever chemicals’ more dangerous than once thought: The guidance may spur water utilities to tackle PFAS, but health advocates are still waiting for mandatory standards, by Dino Grandoni, Washington Post, June 15. 2022.

Two ‘forever chemicals’ more toxic than previously thought: EPA drafts, by Rachel Frazen, The Hill, Nov. 16, 2021.

North Carolina AG sues 14 companies over fire suppressant, Associated Press, Nov. 5, 2021. “Attorney General Josh Stein filed four lawsuits which named 3M, Corteva, and DuPont, among others. In the lawsuit, Stein is asking the court to require the manufacturers to pay for investigations to determine the extent of the damage, clean up the damage, replace water treatment systems and wells, restore damaged natural resources and to monitor water quality.”

Senator, clean water advocates ask for state action after troubling GenX toxicity report, by Johanna Still, Port City Daily, Oct. 31, 2021. “Chemours’ trademark unregulated chemical GenX is more toxic than previously understood, according to a final toxicity report released by the Environmental Protection Agency Monday. The EPA’s new lifetime chronic reference dose for GenX, calculated with the most vulnerable populations in mind, is 3 parts per trillion (ppt). Concentrations of the chemical ingested over a lifetime at or below this threshold are unlikely to lead to negative health effects in humans, the report concludes.”

Forever chemicals widespread in Mass. Surface and ground water, says new report, by Barbara Moran, WBUR, Oct. 29, 2021. “The new analysis of state data follows reports of PFAS contamination in Cape Cod ponds and many Massachusetts rivers, pointing to widespread contamination throughout state lakes, ponds, rivers and aquifers used as sources for drinking water.”

EPA finds chemical contaminating NC river more toxic than previously assessed, by Rachel Frazin, The Hill, Oct. 25, 2021.

Lethal ‘forever chemical’ taint our food, water and even blood. The EPA is stalling, by David Bond, The Guardian, Oct. 24, 2021. “There is no longer any population or place on earth untouched by PFAS contamination. We are living through a toxic experiment with no control group.”

How chemical companies avoid paying for pollution, by David Gelles and Emily Steel, The New York Times, Oct. 20, 2021. “To avoid responsibility for what many experts believe is a public health crisis, leading chemical companies like Chemours, DuPont and 3M have deployed a potent mix of tactics. They have used public charm offensives to persuade regulators and lawmakers to back off. They have engineered complex corporate transactions to shield themselves from legal liability. And they have rolled out a conveyor belt of scantly tested substitute chemicals that sometimes turn out to be just as dangerous as their predecessors.”

Bad Chemistry series of articles by Sharon Lerner, The Intercept, September 2015. “The U.S. has refused to regulate the chemicals in this class, known as PFAS, despite the fact that they persist indefinitely in the environment and have been linked to cancer and many other illnesses.”

EPA unveils new strategy to address US contamination of ‘forever’ chemicals, by Carey Gillam, The Guardian, Oct. 18, 2021. “The US Environmental Protection Agency(EPA) on Monday announced a “strategic roadmap” it said would help restrict a class of toxic chemicals from being released into the environment and accelerate the cleanup of existing contamination of “forever chemicals” that are associated with a range of human health dangers.”

Revealed: More than 120,000 US sites feared to handle harmful PFAS ‘forever’ chemicals, by Carey Gillam, The Guardian, Oct. 17, 2021. “The US Environmental Protection Agency(EPA) has identified more than 120,000 locations around the US where people may be exposed to a class of toxic “forever chemicals” associated with various cancers and other health problems that is a frightening tally four times larger than previously reported, according to data obtained by the Guardian.”

These Everyday Toxins May Be Hurting Pregnant Women and Their Babies: PFAS industrial chemicals may disrupt pregnancy with lasting effects, by Liza Gross, New York Times, September 23, 2020.

Suppressed Study: The EPA underestimated dangers of widespread chemicals, by Abrahm Lustgarten, ProPublica, June 20, 2018. “A major environmental health study that had been suppressed by the Trump administration because of the “public relations nightmare” it might cause the Pentagon and other polluters has been quietly released online.”

The lawyer who became DuPont’s worst nightmare, by Nathaniel Rich, The New York Times, Jan. 6, 2016. “Rob Bilott was a corporate defense attorney for eight years. Then he took on an environmental suit that would upend his entire career — and expose a brazen, decades-long history of chemical pollution.”

The Teflon toxin, three-part series of articles by Sharon Lerner, The Intercept, Aug. 2015. “…. exposes DuPont’s multi-decade cover-up of the severe harms to health associated with a chemical known as PFOA, or C8, and associated compounds such as PFOS and GenX.”

The Teflon toxin goes to court, by Sharon Lerner, The Intercept, Sept. 19, 2015. “DuPont went to court this week, defending its use of C8, the chemical that spread from the company’s Parkersburg, West Virginia, plant into the drinking water of some 80,000 people in West Virginia and Ohio. A jury in Columbus, Ohio, is now hearing the case of Carla Bartlett, a 59-year-old woman who developed kidney cancer after drinking C8-contaminated water for more than a decade.”

Papers: DuPont hid chemical risk studies, by John Heilprin, Associated Press, Nov. 16, 2005. “DuPont Co. hid studies showing the risks of aTeflon-related chemical used to line candy wrappers, pizza boxes, microwave popcorn bags and hundreds of other food containers, according to internal company documents and a former employee.”