Chemicals

PFAS: What We Know, What’s Being Studied, and the Laws

Many stakeholders are following—or should be following—the federal government’s plans to address the impact of per- and polyfluoroalkyl substances (PFAS) on human health and the environment. There is a lot to follow. PFAS are a family of chemicals first synthesized in the 1940s. It is a very large family. According to the EPA’s February 2019 PFAS Action Plan, over 4,000 PFAS may have been manufactured and used in a variety of industries worldwide since the 1940s. The Agency’s Toxic Substances Control Act (TSCA) Chemical Substance Inventory lists about 1,200 PFAS, of which approximately half are known to be commercially active within the last decade.

Chemical research, PFAS

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PFAS are commonly used in nonstick cookware; water-repellent clothing; stain-resistant fabrics and carpets; some cosmetics; products that resist grease, water, and oil; and as fire suppressants used at U.S. military installations and civilian airports and by state and local fire departments.

The federal interest in PFAS is apparent in the more than 40 bills that have been introduced in the current Congress to get federal agencies to do more to tackle aspects of PFAS in the environment and to reduce through regulation the risks PFAS pose to human health.

Persistent and Accumulative

Why, after many years of production and use, are PFAS now attracting so much attention? One reason is their persistence. PFAS have been called “forever chemicals”: Their resistance to degradation is one reason they are so useful in products. But persistence also means that when they enter the human body, they stay there for a long time—up to 8 years by some estimates; persistence also means PFAS accumulate. The Agency for Toxic Substances and Disease Registry (ATSDR) says that most people in the United States have one or more specific PFAS in their blood, especially perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS), the two most commonly studied PFAS. In May 2016, the EPA established lifetime health advisory levels for PFOA and PFOS at 70 parts per trillion (ppt), separately or combined.

Also, despite their long history in society, there is uncertainty about whether PFAS put people at risk and which specific PFAS can cause the most harm. The current intense interest in PFAS probably began around 2000 when 3M, then the only company manufacturing PFAS, notified the EPA that it had obtained information on the potential risks of these chemicals. At that time, 3M became the first company to voluntarily phase out the production and use of PFOA and PFOS. But even with its phaseout, 3M was not admitting that PFOA and PFOS were harming people; the company simply stated that the action was “precautionary.” Also, in 2006, the EPA reached an agreement with a group of manufacturers for the voluntary phaseout of PFOA and related perfluoroalkyl carboxylate chemicals over a 10-year period.

What We Know

Scientists and health researchers have distinguished between the potentially higher risks associated with PFAS with longer fluorinated carbon chains, which are most persistent and, therefore, most effective in products, and shorter chain PFAS, which, because they are less persistent, may pose lesser risks. But right now, there are a long list of “maybes” in discussions of the harms associated with PFAS. For example, the ATSDR states:

“Studies in humans with PFAS exposure have shown that certain PFAS may affect growth, learning, and behavior of infants and older children; lower a woman’s chance of getting pregnant; interfere with the body’s natural hormones; increase cholesterol levels; affect the immune system; and increase the risk of cancer. Scientists are still learning about the health effects of exposures to mixtures of PFAS. For the most part, laboratory animals exposed to high doses of one or more of these PFAS have shown changes in liver, thyroid, and pancreatic function, as well as some changes in hormone levels. Because animals and humans process these chemicals differently, more research will help scientists fully understand how PFAS affect human health.”

Two Study Projects

Industry is resisting any speculative evidence that would lead to restrictions on the manufacture and distribution of useful products with PFAS. 3M and other chemical companies continue to manufacture PFAS today, and their manufacture will likely continue unless science shows with robust evidence that products with PFAS should be kept out of the environment and out of contact with people. To that end, the ATSDR and the Centers for Disease Control and Prevention (CDC) are working on several studies.

  • Multisite health study. On September 23, 2019, the ATSDR/CDC announced the establishment of cooperative agreements with seven partners to study the human health effects of exposures to PFAS through drinking water at locations across the nation. The goal of the study is to learn more about the relationship between PFAS exposure and health outcomes among differing populations. Study partners will collect information about immune response, lipid metabolism, kidney function, thyroid disease, liver disease, glycemic parameters, and diabetes. The ATSDR/CDC will also collect information about cancers, but the size of the study is not large enough for them to effectively evaluate the relationship between PFAS exposure and cancer. The multisite study seeks to enroll at least 6,000 adults and 2,000 children. To look at cancer outcomes, a study would need to enroll many times those numbers.
  • Pease Study. This study involves people living near the Pease International Tradeport in Portsmouth, New Hampshire, who obtained drinking water from a source contaminated with PFOS. In 2014, sampling showed levels of PFOS in three drinking water wells. The level in one well far exceeded the 70 ppt health advisory set by the EPA. The well was shut down by the city of Portsmouth in May 2014. The intent of the study is to evaluate the human health effects of exposure to PFOS in drinking water. The ATSDR/CDC are recruiting children aged 4 through 17 and adults aged 18 and older who were exposed to PFOS-contaminated drinking water in wells near the Tradeport between 2004 and May 2014; the participants will provide blood and urine samples, as well as their medical histories. It is believed that drinking water is the dominant exposure route for PFAS.

“Understanding the relationship between PFAS exposure and health outcomes will allow communities and governmental agencies to make better decisions about how to protect public health,” say the ATSDR/CDC.

Many other studies of PFAS have been conducted or funded by other federal agencies, including the EPA, the Food and Drug Administration, the Department of Agriculture, and the Department of Defense (DOD). In its Action Plan, the EPA indicates that it is leading the national effort to understand and reduce PFAS risks to the American people. In this endeavor, the Agency states that it seeks “active engagement with other federal agencies, international organizations, states, tribes, industry groups, associations, local governments, communities, and the public.”

Looking at the Laws

Probably the main reason the EPA has taken the lead on the national PFAS research program is that the Agency has significant existing authority to regulate PFAS under multiple statutes. In an October 2019 report, the Congressional Research Service (CRS) summarized these authorities.

TSCA. Given that PFAS are manufactured chemicals used in commerce, TSCA would appear to offer the most opportunities for regulation, and the EPA has exercised some of those options. Primarily, under the reporting obligations affecting manufacturers and processors under TSCA Section 8(e), the Agency has obtained information on the risks of various PFAS to assess if such risks may be unreasonable, warranting regulation under the statute. For example, as noted above, information on PFAS was obtained in 2000 from 3M and later from other companies who identified risks.

In addition, subsequent to the various phaseouts also noted above, the Agency promulgated Significant New Use Rules (SNURs) under TSCA Section 5(a)(2) to require any manufacturer to notify the Agency before reintroducing these chemicals into commerce for historical uses.

Under Section 5(a)(1), the EPA has also continued to evaluate the risks of new chemicals, including new PFAS, as manufacturers have notified the Agency of their intent to produce these chemicals.

In 2005, the EPA announced a settlement with DuPont for reporting violations under TSCA Section 8(e) and the Resource Conservation and Recovery Act (RCRA) that involved PFOA. According to the EPA, the settlement required DuPont to pay $10.25 million in civil penalties and perform Supplemental Environmental Projects valued at $6.25 million.

The EPA has not used its TSCA Section 6 authority for any PFAS. Section 6 allows the Agency to establish regulatory controls on any stage of the life cycle of a chemical (i.e., manufacture, processing, distribution, use, and disposal) if such controls would be necessary to mitigate “unreasonable risk of injury to health or the environment.” Also, no PFAS is on the list of 10 chemicals the EPA prioritized in 2016 for risk evaluation under Section 6.
Drinking water
Safe Drinking Water Act (SDWA). Under the SDWA, the EPA promulgates maximum contaminant levels (MCLs) and maximum contaminant level goals (MCLGs) for substances in drinking water that may endanger human health and for which regulation is viewed as a way to mitigate risk. In addition, every 5 years, the Agency must identify emerging contaminants that may warrant regulation, issue an Unregulated Contaminant Monitoring Rule (UCMR), and make a regulatory determination (RD) as to whether to promulgate a drinking water regulation for at least five contaminants on the Agency’s contaminant candidate list.

In 2012, the EPA issued its third UCMR under which 4,864 public water systems tested their drinking water for six PFAS—including PFOA and PFOS—between January 2013 and December 2015. Overall, 63 of the 4,864 water systems (1.3 percent) reported at least one sample with PFOA and/or PFOS concentrations (separately or combined) exceeding the EPA’s health advisory level of 70 ppt. According to the EPA’s Action Plan, the Agency intends to propose monitoring requirements for other PFAS in the next UCMR in 2020.

In 2014, the EPA published preliminary RDs for contaminants, including PFOA and PFOS.

Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). Section 104 of CERCLA or Superfund authorizes the president to respond to releases of CERCLA-listed hazardous substances into the environment, as well as releases of other pollutants or contaminants that may present an imminent and substantial danger to public health or welfare. CERCLA Section 107 establishes liability for response costs and natural resource damages.

Currently, no PFAS is designated as a hazardous substance under CERCLA. In its Action Plan, the EPA has indicated that it is developing a rule to designate PFOA and PFOS as hazardous substances under CERCLA Section 102 or other related laws that trigger a CERCLA hazardous substance designation. One such trigger is a hazardous substance designation under Section 311(b)(2)(A) of the Clean Water Act. An SDWA designation of an MCL for any PFAS would not trigger a hazardous substance designation under CERCLA. Several bills introduced in Congress would require the EPA to issue a rule designating all PFAS as hazardous substances under CERCLA.

The EPA has included sites with PFAS contamination in the Superfund program, although most of these sites have also been contaminated with CERCLA hazardous substances.

At present, the DOD is the CERCLA responsible party for the most sites with PFAS releases. Virtually all these releases resulted from the DOD’s use of fire suppressants containing PFAS at military installations. More than half the bills introduced in Congress would require the DOD to continue its current work to remediate PFAS sites and undertake new PFAS-mitigation actions, as well.