By Brita E. Lundberg, MD and Michael Bader, MD
PFAS, short for per- and polyfluoroalkyl substances, are a class that includes over ten thousand chemicals that contain at least one fully fluorinated carbon atom. The carbon-fluorine bond, the strongest chemical bond known, is exceptionally rare in nature;
nothing in nature can break this bond down. This makes these chemical compounds exceptionally resistant to degradation, leading them to be called “forever chemicals.”
Health effects
According to the U.S. Environmental Protection Agency (EPA), there is no safe level of exposure to PFAS.
While the EPA has set regulatory levels at between 0.002 and 0.004 ng/L, the EPA notes that, like the neurotoxicant lead, the carcinogen benzene, and radiation, the health effects of PFAS may be seen at every level of exposure.
The associated health harms of the chemical class are broad: epidemiologic and toxicologic studies have linked PFAS to reproductive, endocrine, and neurodevelopmental diseases, as well as to some cancers. The chemicals are known to be associated with
infertility, preeclampsia, low infant birth weight, Type 2 diabetes, early-onset puberty, thyroid disease, impaired vaccine response, neurocognitive impairment in children (decreased IQ), and malignancies, including kidney and testicular cancers.
The health effects of in utero or early childhood exposure may not be obvious until years later.
High-risk populations include children, pregnant women, industry workers, and those who live or work near high-risk facilities such as military bases, shipyards, chemical plants, refineries, or airports.
Newer short-chain “GenX” PFAS have been developed and were hoped to be less toxic, but epidemiologic studies of community contamination in North Carolina suggest that these newer chemicals are as harmful to health as legacy PFAS.
Where PFAS are found
The first PFAS were used in nuclear weapons development by the Manhattan Project during World War II. Since then, their purported stain and water-resistant characteristics have led to their adoption in a plethora of applications and wide-scale use in
thousands of products, including weapons, “non-stick” products, paint, artificial turf, clothing, leather, carpets, food packaging, firefighting foam, pesticides, petroleum extraction (“fracking”) fluids, and wastewater sludge or “biosolids” that
are spread on agricultural crops. They have also been used in medications, breast prostheses, contact lenses, IV tubing, cannulas, and joint spacers.
Exposure pathways: Trojan chemicals
Humans are exposed to PFAS via air, soil, food, and water; the latter is thought to be the most common source of exposure.
PFAS are present in air and dust; the chemicals can aerosolize from carpets and upholstery and be inhaled. PFAS can be ingested or absorbed through the skin or gut from water (rain, rivers, and water systems) or can leach into food via packaging, pesticides,
and fertilizer. PFAS has even been found in rainwater at levels harmful to humans.
Among infants, toddlers, and children, hand-to-mouth behavior is a significant source of exposure.
Ubiquitous exposure
Over 97 percent of the US population has detectable PFAS blood levels. Globally, over six hundred thousand acres of urban and
agricultural land are contaminated with PFAS. According to a new study from the US Geologic Service, almost half of US water systems are contaminated with the forever chemical.
Mechanism of disease: a free fatty acid mimic
PFAS are known to methylate DNA, which impairs gene expression, and they can act as free fatty acid (FFA) mimics.
Since free fatty acids bind albumin, a key transporter, this molecular mimicry permits PFAS to be delivered to every part of the body, where it can have negative effects on metabolism, organ development, and endocrine function. But these two mechanisms
of disease do not explain all the adverse health effects that are associated with the chemicals.
Equity
PFAS also pose an important equity issue. A recent Harvard TH Chan study showed that Hispanic and non-Hispanic Black populations are more
likely to have community water systems contaminated with PFAS.
Moreover, while both wealthy and low-income communities are affected by PFAS pollution, wealthy communities are more likely to be able to afford high-cost mitigation measures, such as water filtration.
Thus, the health harms of PFAS and the ability to respond to them exacerbate existing health disparities.
Economic Costs of PFAS Contamination
PFAS contamination is a very costly issue for communities in Massachusetts. Cambridge, for example, spent $2 million a month in 2022 to source its water from MWRA while it installed filters for PFAS due to elevated levels. Hyannis, which had the
highest PFAS levels in the state, spent $10 million in 2015 on a filtration system; Barnstable installed one in 2019 for $20 million.
Yet the cost of water filtration is dwarfed by the cost of the health consequences of PFAS. Researchers from NYU estimate that the economic costs of the health sequelae in the US range from $5.5 to $63 billion annually.
Communities can’t shoulder these costs alone. Last year, the Massachusetts Department of Environmental Protection (DEP) testified to the specific need for funding for testing and remodeling private wells. While the DEP is increasing its PFAS budget, the
agency said that stronger legislation is required to address this public health issue.
Mitigation works
When water filtration systems are installed, local PFAS levels have been shown to decrease. One clinical study in Minnesota found that reducing PFAS chemicals in the water supply had measurable positive health effects: PFAS blood concentrations were substantially reduced in the population, and there were significant, albeit modest, improvements in infant birth weights
and reductions in preterm births.
Talking to patients about prevention
Physicians can counsel patients to:
- Avoid highly packaged/processed foods.
- Test their municipal and private well water for PFAS.
- Be aware of levels of contamination in the community, especially if breastfeeding; consider blood testing if local levels are high.
PFAS blood tests are now commercially available. Testing for PFAS, though expensive, offers an opportunity to identify people who may need to reduce PFAS exposure and who are at increased risk of certain health outcomes. We maintain that PFAS blood testing
should be covered by insurance, as lead testing is, so that patients who already have difficulty finding clinical preventive services for reasons of race, age, and other social and demographic factors have equal opportunity to access PFAS testing
and the accompanying exposure reduction counseling.
Also, better methods of testing are needed, as current testing only identifies legacy PFAS, not the newer GenX chemicals.
How to address PFAS exposure
Information on reliable companies offering PFAS blood testing and how to interpret them is available on the PFAS-Exchange website, a joint collaboration between
the Silent Spring Institute, Northeastern University, and Michigan State University.
How to interpret blood tests is described in a 2022 National Academies of Science and Medicine (NASEM) report,
summarized in short as:
- Adverse health effects related to PFAS exposure are not expected at less than 2 nanograms per milliliter (ng/mL).
- There is a potential for adverse effects, especially in sensitive populations, between 2 and 20 ng/mL.
- There is an increased risk of adverse effects above 20 ng/mL.
PFAS water testing: Massachusetts is one of the first states in the country to require testing for PFAS in water. In 2020, MassDEP published standards for PFAS in drinking and ground water; this rule covers a subgroup of six related prevalent PFAS
chemicals due to their high toxicity and persistence. The Massachusetts DEP has set a PFAS limit of 20 ppt in municipal water systems. MassDEP recommends that all private drinking water wells be tested for PFAS contamination.
Ways to eliminate the body burden of PFAS
PFAS are eliminated from the body in women via menstrual blood loss and nursing (however, it then bioaccumulates in the nursing infant). Some are
excreted. Recent studies have shown that blood and plasma donations may also be used to reduce serum PFAS levels.
How to eliminate PFAS from home water systems
Activated carbon filters are used by both water utilities and individuals to remove PFAS from drinking water, but the carbon filters become contaminated
and can go on to contaminate landfills. Ion exchange (IO) and reverse osmosis systems can also be used in homes, but if selecting IO, check that the filter
meets NSF/ANSI guidelines.
US EPA and others to set regulatory limits
PFAS have recently been designated by the US EPA as hazardous substances that can be regulated under Superfund statutes. The EPA has also recently proposed new national standards that would limit the concentrations of six PFAS in public drinking water
supplies. But many scientists feel that this is not sufficiently protective of health and that it is necessary to regulate not just six PFAS but to regulate PFAS as a class, which includes thousands of PFAS.
While industry has retired many legacy PFAS, the newer fluorocarbons contaminate the environment via the same routes and are associated with similar health hazards.
The European Chemicals Agency has proposed a ban on the production, use, and sale of about 10,000
PFAS chemicals. If adopted, the ban will apply to the entire EU.
Finding solutions to PFAS: prevention, mitigation, treatment, and increasing public awareness
PFAS is the "lead" of our time. Like lead, PFAS chemicals are ubiquitous and represent a costly public health and health equity issue. Increased public education around this issue is critical, as is advocacy for more stringent regulations on products
containing PFAS. Regulating PFAS as a class, as called for in this NEJM perspective, would better mitigate these many health effects
since they derive from many different PFAS, not just the legacy ones targeted by the EPA. A stronger policy would also help ensure that the companies responsible for the pollution would bear the cost of cleanup.
Legislative action on PFAS is justified and urgently needed, given the tremendous health and economic costs of this issue. The familial, societal, and economic costs are immense, and the disabilities can be life-long.
Decreasing toxic exposure to PFAS will improve the health of adults and children in the Commonwealth.
The MMS has supported legislation at the State House that would:
- Ban non-essential PFAS use in Massachusetts.
- Regulate PFAS as a class.
- Establish a fund for drinking water remediation, including private well remediation.
- Require that the MA Department of Environmental Protection (DEP) restrict industry discharges of PFAS to groundwater and surface water.
- Require quarterly monitoring and reporting of PFAS.
- Engage in a critical public outreach program on the dangers of PFAS.
- Vest in the state Attorney General the authority to enforce violations of PFAS laws.
- Require that MassHealth and state insurance companies cover PFAS blood testing.
Doctors can:
- Provide information about sources of exposure to PFAS, PFAS health effects, and blood testing in doctors’
offices and at medical facilities. Comprehensive medical information and guidance that can be shared with patients can be found on the PFAS-EXCHANGE
project’s website.
- Advocate to the state legislature to reduce future community exposure through regulations to curb the continued production and use of PFAS; by excluding PFAS from common consumer products such as food packaging, textiles, personal care products, and
pesticides; and by banning discharges into groundwater, lakes, and rivers from use in biosolid fertilizer and artificial turf.
- Screen patients for the following environmental exposures: contaminated drinking water; occupational exposure, such as firefighting foam and gear; and residence in close proximity to airports, incinerators, or military bases.
- Become an advocate for PFAS-removing water filtration systems to be installed in homes and public water supplies where elevated PFAS levels are detected.
- Advocate that the Commonwealth of Massachusetts follow New Hampshire’s lead in requiring that robust blood tests for PFAS be covered by insurance so that clinicians and patients can assess exposure and health outcomes can be monitored to protect the
health of the population.
Conclusion
PFAS pollution is a ubiquitous toxicant, but the host of illnesses they spawn are not inevitable; they are preventable diseases. Like the public health response to the health threats posed by lead and secondhand smoke, which resulted in a gratifying improvement
in children’s IQ and decreased incidence of lung cancer, the response to PFAS could be a public health success story. The time to act is now.
Addressing PFAS contamination using a systematic public health approach — education, mitigation, prevention, and advocacy — will benefit all communities across the Commonwealth.
References
