Researchers from ACES along with colleagues from Switzerland, and the United States call for intensified global research and regulation on the vast number of highly fluorinated substances, or PFASs currently on the market, in an article published in Environmental Science and Technology. They stress that while there has been much research and regulation on a limited selection of well-known PFASs, the majority of these substances continue to be overlooked.
Highly fluorinated substances, commonly referred to as PFASs, are a family of chemicals that have been produced since the late 1940s and due to their unique properties they have been used for a wide variety of industrial and consumer applications such as cosmetics, textiles, food contact materials, fire-fighting foams, household products and many others. More than 3000 PFASs are, or have been, available on the global market to date and new ones are being developed every year. Yet information about their chemical properties or production is often missing.
“I have been frustrated that at recent international conferences nearly every presentation is focused on a few well-known substances such as PFOS and PFOA, whereas the vast majority of the 3000 PFASs on the market continue to be overlooked. It is high time for scientists to come up with approaches for tacking the whole group of PFASs and hopefully this feature will raise awareness of this important issue,” says Ian Cousins, co-author of the paper and professor at Stockholm University.
Due to the strength of the chemical bond between carbon and fluorine, PFASs are highly resistant to degradation under natural conditions. Even though some PFASs may partially degrade in the environment and biota, they will all ultimately transform into highly stable end products. The very high persistence of PFASs leads to increasing levels in local/regional environments, including groundwater, and their long-range transport, resulting in global contamination.
“The fact that we are still learning what sorts of PFASs are potentially contaminating drinking water supplies is a bit disconcerting” remarks Christopher Higgins, a co-author of the paper and associate professor at the Colorado School of Mines, USA. He continues: “Sharing knowledge and information across disciplines and borders is more critical than ever if we are going to effectively tackle this challenging issue.”
In addition to their problematic high persistence and long-range travel potential, some PFASs are toxic. For instance, certain PFASs have been shown to cause multiple effects in animal studies (e.g. liver damage) and there is evidence for links between exposure and several diseases for highly-exposed human populations. Large uncertainties remain however regarding the toxicity of most PFASs.
The Feature further explains that, due to the vast number of PFASs, it is neither sensible nor feasible to assess all of them individually within a reasonable time frame. It therefore recommends future research to be more targeted than today’s and provides a list of recommendations for how this could be achieved. In addition to targeted research, effort is still needed to manage all the existing PFASs.
“We have previously advocated a precautionary approach to the management of PFASs in several earlier publications,” says Ian Cousins.
For example, in the Madrid Statement, signed by over 200 international scientists, it is recommended that the production and use of most, if not all PFASs, should be phased out. In practice though, as pointed out in the article, it can be technologically challenging to develop alternatives in some essential use categories that simultaneously provide the desired functionality and are safe for humans and the environment.
“We are using these chemicals in a wide range of applications where they are non-essential,” says Dr. Zhanyun 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?” he asks. “The public needs to be involved in defining “essential” and “non-essential” uses, and industry needs to develop safer alternatives for essential uses.”
To learn more about PFAS watch this video interview with ACES professor Ian Cousins