Page 2: "A difficult problem"

Contents

In some cases, PFAS can also be eliminated from a product or process without the need for a substitute substance. One example of this is baking paper. Baking paper can be made greaseproof by grinding and pulping the wood differently during paper production. The paper then becomes greaseproof without the addition of impregnating agents such as PFAS.

heise online: How great is the risk of unintended consequences with such a replacement?

Scheringer: As the alternatives are tested extensively, this risk is small. In many cases, extensive development work is required, during which a lot is learned about the alternatives. There are numerous, often smaller, companies that invest a great deal in the research and development of alternatives to PFAS, and that is very valuable.

It is important to give these companies sufficient support. In addition to these small, innovative companies, it is often also the big consumer product brands that are driving the change because they actively market PFAS-free alternatives and see a clear advantage in this.

heise online: As an observer, you sometimes get the feeling that companies are happy to swap substances that have been dubbed negative in the media for other, less well-known substances. I'm thinking of bisphenol A (BPA), for example, which has controversial alternatives.

Scheringer: This is a difficult problem. Substances that have the same or a similar function as a problematic substance often also have similar disadvantages. Ultimately, you have to build a product or a process differently if you really want to (or have to) work with other substances.

This means expenditure on research and development, and also costs. However, the problematic substance that is to be replaced also causes costs and problems, so we should not only consider the costs of the change, but also the costs of continuing as before.

heise online: How does the handling of PFAS differ in different regions of the world, what do the EU, USA or China do differently? Is it possible to agree on common goals in the exchange?

Scheringer: Many regions of the world have very similar problems with PFAS, especially the widespread pollution of groundwater and then often drinking water - and the resulting exposure of the population and the need for remediation options. In this respect, science, authorities and industry are faced with the same questions everywhere, and there is a lot of exchange and a desire to learn from other regions.

However, as the legal frameworks are different, the specific approaches also vary. Regardless of this, the common goals are, on the one hand, to find ways of dealing with existing pollution. And on the other hand, to develop alternatives to PFAS.

heise online: What approach is recommended for companies or entire industries when making this change?

Scheringer: Companies should tackle the switch to PFAS-free alternatives together with others from the same industry. When looking for alternatives, they can discuss what works and what doesn't work, and ideally they will then benefit from each other. Of course, there is a need not to disclose technical developments, but sharing and mutual learning would still be possible to some extent, partly organized by industry associations.

In many areas, the switch to alternatives is already underway and there is experience with alternatives. The key question is always how important PFASs actually are for a particular product or process. In many cases, PFAS can be replaced relatively easily. However, there are also industrial applications, e.g. in the semiconductor industry, where this is more difficult. But even in this sector, companies are in the process of developing and testing alternatives. The "Chemicals Secretariat", ChemSec, offers a lot of valuable information on the change in various industries.

heise online: What should be done if PFAS-free alternatives do not perform as well as PFAS?

Scheringer: This depends very much on the function that PFAS have in a product or process. There are many areas of application in which the alternatives are now as good as PFAS, especially in consumer products that I have already mentioned, such as impregnation and cleaning agents. On the other hand, there are also areas where the special properties of PFAS - water and oil repellent, very stable and resistant, highly surface-active - are not achieved to the same extent by the alternatives.

However, this is not surprising, as the alternatives are chemically different from PFAS - and are supposed to be. In these cases, it is necessary to check whether the special properties of PFAS are actually needed, as this is not always the case. It may be necessary to structure or organize a product or process differently so that a substance with less pronounced properties is sufficient after all.

heise online: In your essay, you call for the industry to take a proactive approach - and also to seek advice from research in order to compensate for performance differences.

Scheringer: Companies should work closely with materials scientists and engineers, including at research institutes, who have ideas based on their experience of how the function of PFAS can be fulfilled as well as possible in other ways. This is, of course, an iterative process that takes time - this must be accepted.

However, these high requirements only exist in some areas. In many cases, the performance of alternatives is close enough to that of PFAS. My favorite example is the firefighting foams I mentioned: they are very demanding, but it was already possible in 2003 to develop PFAS-free alternatives that are equivalent.

And finally: the switch to PFAS-free is not a luxury project of bored government officials and scientists, but necessary because millions of people throughout Europe are contaminated with PFAS and municipalities and water suppliers are facing enormous costs. There are therefore very good reasons to demand and promote the elimination of PFAS.

The interview was conducted by e-mail.

(vbr)