In a peer-reviewed study released this week by Environmental Science and Technology, four prominent scientists (including Christopher Higgins of the Colorado School of Mines) call for strict regulation and a possible worldwide ban of an entire class of fluorinated chemicals related to those that contaminated wells and drinking water systems in Fountain Valley.
The contamination was subsequently linked to the use of long-chain perfluorinated substances in firefighting foam used at Peterson Air Force Base.
First synthesized in the 1940s, perfluoroalkyl substances have been used in a variety of industrial and consumer applications, including cosmetics, firefighting foams, food contact materials, household product inks, medical devices, oil production, pesticide formulations, leather and apparel. Exposure to these chemicals has been linked to cancer, elevated cholesterol, decreased fertility, thyroid problems and changes in hormone functioning in adults, as well as adverse developmental effects and decreased immune response in children.
This class of chemicals, including long- and short-chain, per- and polyfluorinates, doesn’t break down and can stay in the environment for thousands of years.
In recent years, according to Dr. Arlene Blum of the Green Science Policy Institute, scientists have increasingly widened their focus. Rather than concentrate on a few provably toxic long-chain perfluorinates (such as those found in Fountain Valley water), they’re examining the whole family of per- and polyfluorinated substances.
As long-chain PFASs are phased out worldwide, chemical companies have replaced them with thousands of chemically similar short-chain fluorinates. For scientists trying to assess the dangers of these newly created chemicals, it’s a frustrating game of whack-a-mole.
“The most common current industrial practice of phasing out one PFAS is to replace it with another [or multiple other] structurally similar PFASs,” the study said.
“Such a strategy is easier and less costly than identifying a nonfluorinated substance to be used in the same or similar process or inventing a new process that does not require PFASs. … Such replacement strategies… will only increase the numbers of PFASs on the market and the difficulties in tracking them. Consequently, there is a proliferation of new PFASs on the market, which will likely continue in the foreseeable future.”
For example, long-chain PFASs in firefighting foams have been phased out, replaced by short-chain PFASs. It may take years to determine whether these chemicals are as toxic as their predecessors. And since there are thousands of such substances in use, the task of testing and monitoring all of them would likely be impossible.
“Current data suggest that the replacement chemicals are just as likely- -… to end up in our drinking water and in our crops.”
— Christopher Higgins
“The chemical industry claims the replacements for the phased-out chemicals are safe because many do not build up in humans like the old ones did. Nonetheless, we are constantly exposed if these chemicals are in the food we eat or the water we drink,” Higgins said. “Current data suggest that the replacement chemicals are just as likely- -— if not more likely- — to end up in our drinking water and in our crops.”
“I am concerned that researchers and regulators are continuing to focus on a few phased out chemicals rather than the thousands of related substances in use today,” said Dr. Ian Cousins, co-author of the paper and a professor at Stockholm University.
“We are using these chemicals in a wide range of applications where they are non-essential,” said Dr. Zhanyung Wang, lead author of the article and senior scientist at ETH Zurich, Switzerland. “Maybe we need them for a Himalayan expedition, but do we really need them in our surf shorts or our blue jeans?”
Yet the process of mitigating hazards and removing such chemicals from the environment is so expensive and time-consuming that a global ban may make sense.
But it won’t be easy. PFASs are produced and created in dozens of countries, all with their own regulations and protocols. A product deemed harmful in Sweden, Denmark or the United States may seem benign or even useful to regulators in China, India or Vietnam.
“Given the unique properties of PFASs,” the study concludes, “it can be challenging to identify functional alternatives in some essential use categories. Let us start the dialogue in defining ‘essential’ and ‘non-essential’ uses of PFASs, while simultaneously developing safe alternative substances and processes for those essential uses.”
As Blum concedes, some damage may be irreversible. Yet as a world-renowned mountaineer, she is hopeful.
“Himalayan mountain climbers are acute optimists,” she said, “and I think that purchasers and consumers will make good decisions. IKEA, Crate & Barrel and 60 outdoor clothing companies are eliminating all highly fluorinated products from their products, and I think others will follow.”