Last month, a group of scientists scored an unexpected win in chemical regulation: The state of Maine became the world’s first jurisdiction to ban the sale of products containing per- and polyfluoroalkyl substances (PFASs). The controversial chemicals are common in consumer goods such as nonstick cookware. By 2030, Maine will forbid selling products that use PFASs unless regulators determine their use is “currently unavoidable.”
The law, adopted 15 July, targets a family of chemicals that includes some 5000 compounds, including several banned under the international Stockholm Convention because they threaten human health. Because PFASs have a similar basic structure that can persist in the environment for long periods, some researchers have argued governments should drop the traditional approach of regulating them one by one. Instead, they want regulators to restrict the entire class, requiring manufacturers who want to use a PFAS in a product to prove the chemical’s use is “essential” for health, safety, or the functioning of society, and that there are no alternatives.
The essential-use approach “is really about trying to find more efficient regulatory means to control something that has been identified as hazardous,” says Kathleen Garnett, an environmental law scholar at Wageningen University & Research’s Law Group and a proponent of the idea.
Industry groups, however, have pushed back, saying the approach is not rooted in science and could put useful chemicals off limits. “A one-size-fits-all approach to chemical regulation is neither scientifically accurate, nor appropriate,” said the American Chemistry Council in a recent statement on the Maine law.
For decades, manufacturers used PFASs to create materials that repel water and stains and make fire-fighting products. The compounds’ basic structure—a string of carbon atoms swathed in fluorine—resists degradation, earning them the nickname “forever chemicals.” After two PFASs were linked to health problems in the 1990s, major manufacturers—including 3M and DuPont—voluntarily replaced them with related compounds they said were safer. Since then, many communities in the United States and elsewhere have discovered PFASs in their water supplies, sparking extensive legal and political battles over cleanups.
In the meantime, regulators and researchers have struggled to determine the risks posed by PFASs that are now in use. One challenge has been that companies are often unwilling to share information with outside scientists, notes analytical chemist Xenia Trier of the European Environment Agency, who says she could not properly measure PFASs in food packaging in Denmark because companies did not cooperate. Another challenge has been that manufacturers change the specific PFASs they use, making it difficult for scientists and regulators conducting risk assessments to keep up.
In 2013, PFAS researchers discussed such frustrations at a meeting that Trier and environmental scientist Ian Cousins of Stockholm University organized in Helsingør, Denmark. “There was a clear bubbling [of] a certain sense of urgency and concern,” recalls Martin Scheringer, an environmental chemist at ETH Zurich. The discussions resulted in a document, known as the Helsingør Statement, that summarized key concerns about PFASs and research needs. It also urged that PFASs “only be used in applications where they are truly needed and proven indispensable.”
That idea wasn’t new. In the late 1970s, the U.S. government pioneered the essential-use approach in restricting chemicals that harm Earth’s protective ozone layer. It allowed the use of ozone-destroying chemicals that were important for health and safety—such as propellants in asthma inhalers—but banned uses in products such as hairsprays. Several international pacts to control pollutants adopted similar ideas.
After the Helsingør meeting, Trier, Cousins, and their collaborators fine-tuned their ideas about how to apply the essential-use concept to PFASs and, in 2017, founded the Global PFAS Science Panel to focus on the issue. “We kind of had this mission that we wanted to phase [PFASs] out of society,” Cousins says. In May 2019, Cousins and other scientists provided examples of how the policy might work in Environmental Science: Processes & Impacts. They noted, for example, that using PFASs to make highly water- and oil-repellant surgical gowns and firefighting gear could be considered an essential use, but using the compounds in rain jackets or surfing gear would not.
The idea has made some headway. In October 2020, the European Union announced a Chemicals Strategy for Sustainability, which includes a proposal to ban PFASs except for essential uses. In China, a January update to a key chemical law asks manufacturers to explain why use of a hazardous substance is necessary.
The new Maine law, however, is one of the strongest embraces yet of essential use. In 2019, officials discovered PFAS pollution is widespread in the state, even though the chemicals are not manufactured there. Legislators wanted “an approach to PFASs that gets to the root of the problem,” says Patrick MacRoy of the nonprofit Defend Our Health, which helped shape the law. “That was a very deliberate decision.”
Maine and other governments that adopt essential-use policies are likely to face fierce disputes over which chemicals should be included in the PFAS family—and which uses will be defined as essential. PFAS manufacturers, for example, want large molecules known as fluoropolymers excluded, arguing they should not affect health because the molecules are too big to be absorbed by humans and other animals. (Some scientists, however, point out that manufacturing fluoropolymers often involves smaller PFASs, and historically PFAS pollution originated at facilities that made fluoropolymers.)
Even as these debates heat up, some companies are removing PFASs from their products. An Oregon-based company, KEEN Footwear, recently eliminated PFASs from shoes. Large cosmetics brands, such as Sephora, have pledged to follow suit.
In the meantime, researchers pushing the essential-use concept are thrilled by the recent policy developments. Cousins, for example, is “superexcited” about the Maine law. “I just hope it holds.”
science.org, 27 August 2021