The Future of Circular Materials and Compliance: An Interview with Philippe Dewolfs

Biography

Philippe Dewolfs is leading TÜV AUSTRIA OKcert, a leading international certification body specializing in biodegradable, compostable, bio-based, and renewable products. Since 1995, OKcert has provided independent, science-based certification schemes that help ensure the credibility and transparency of environmental claims across global markets. He is the author of the book “The OK eco-system”, which compiles some sixty texts illustrated with sketches posted on LinkedIn in recent years and presents various concepts of certification in the field of sustainable development. The OK eco-system brings together well-known certification schemes such as OK compost, OK biodegradable, OK bio-based, and OK renewable, offering a harmonized framework that can be applied across industries and regions. This work supports manufacturers, brands, policymakers, and other stakeholders in navigating complex regulatory and environmental requirements, while addressing key challenges such as greenwashing, material verification, and comparability of sustainability claims. The OK eco-system is widely used as a practical reference for implementing reliable certification in the context of the circular economy. Through his involvement in certification development and coordination, Philippe Dewolfs contributes to the broader effort to align innovation, standardization, and environmental responsibility, supporting the transition toward more sustainable products and materials.

 

• Future: You’ve led certification initiatives such as OK compost and OK renewable— how do you see certification schemes evolving over the next 5–10 years to keep pace with novel bio-based and chemically recycled materials?

Mr. Dewolfs: The evolution of certifications will follow a clear trend: moving from a ‘single-criterion’ approach (compostability, bio-based, recycled) to a systemic approach, incorporating the concept of renewable carbon as defined by the Renewable Carbon Initiative and adopted by OK renewable. This approach makes it possible to combine bio-based, recycled, and captured (CCU) carbon sources, thus avoiding fruitless opposition between sectors. This is a major change: the carbon in a product will no longer be assessed according to its single origin, but according to its overall contribution to defossilisation.
The schemes will also need to incorporate the growing importance of mass balance for the origin of materials, but it should be noted that this approach is not applicable in the case of end-of-life treatments, as it is essential that the targeted characteristics (biodegradability, etc.) are effective for the materials in question. As a certifier, we must therefore pay close attention to developments in new materials, manufacturing and recycling processes, assessment standards, as well as the needs of industry, authorities and citizens, to offer robust and reliable certification schemes.

• Future: Regulations such as the EU’s PPWR are reshaping packaging requirements. From TÜV AUSTRIA’s perspective, what are the biggest technical and implementation challenges you see for manufacturers and certification bodies?

Mr. Dewolfs: The PPWR introduces stricter definitions (e.g. coffee capsules), requirements for recyclability ‘in practice and on a large scale’, and the future standardisation of anaerobic digestion, home composting and industrial composting. For manufacturers, one of the main challenges will be material compatibility and managing the variability of recycled streams. For certification bodies, the challenge is threefold:
* Quickly translate these new requirements into clear schemes, as OKcert has historically done even before the standards were published (e.g. OK compost INDUSTRIAL developed in 1995, five years before the standard was published).
* Maintaining technical neutrality in a context where legislators allow for certain national margins.
* Ensuring market surveillance in the face of the accelerated risk of greenwashing linked to the new obligations.
As a certifier, we are participating in the revision of these standards.

 

 

• Future: There’s widespread confusion in the market between ‘bio-based’, ‘biodegradable’, and ‘compostable’ claims. What concrete steps should industry, certifiers, and regulators take to reduce greenwashing while still encouraging innovation?

Mr. Dewolfs: These terms are neither synonymous nor interchangeable. Confusion is the number one source of greenwashing, whether deliberate (for commercial gain) or unintentional (through ignorance).
Each party has a role to play.
Certifiers must implement tools to clarify the message, for example, by using clear and understandable logos. TUV AUSTRIA also contributes to this objective by monitoring the market and pursuing fraudsters or those who use confusing messages. However, we can only intervene in cases involving statements that refer to our (registered) conformity marks.
Fraudulent generic claims (biodegradable, good for the planet, eco-friendly, etc.) must be monitored by the relevant public authorities.
It is not enough to legislate, as is too often the case, but it is also necessary to finance the monitoring of the application of these laws.

 

• Future: You’ve been involved with international standardization and working groups. Which standards or test methods do you think need the most urgent revision for them to be future-proof (e.g., for home composting, advanced recycling outputs, microplastic testing)?

Mr. Dewolfs: There are several standards that warrant priority updating or development:
– Composting
* Industrial: the EN 13432 standard needs to be revised. This is a major challenge, as it is intrinsically linked to the new PPWR, and major changes are to be expected given that it has not been revised since its initial publication in 2000. I advocate harmonisation between all standards dealing with industrial composting.
* Domestic: there is a standard (EN 17427) for single-use bags (regardless of their material (plastic, paper, etc.). In technical terms, it would suffice to extend its scope of application.
Anaerobic biodegradation (methanisation): there is an urgent need to develop testing and specification standards to enable this technology to develop. There are currently several processes (mesophilic or thermophilic, wet or dry, etc.) that make standardisation, and therefore testing, certification, and communication, difficult.
* Microplastics, whether primary (deliberately added) or secondary (resulting from the fragmentation of various products), are a major issue.
Here, one of the problems for a certifier lies in the technological capacity to detect very small particles (less than 10 µm) at a reasonable cost so that they can be implemented on a large scale.

 

 

• Future: Digital traceability and product passports are emerging solutions for circularity. How can certification marks (like OKcompost / OKbiobased) integrate with digital systems to provide real-time trust and supply-chain transparency?

Mr. Dewolfs: The labels in the OK family from TÜV AUSTRIA can be integrated into product passports by providing verifiable data: Scode, which identifies the manufacturer of the certified product, certificate reference, the main data for which can already be found on our website (https://okcert.tuvaustria.com/database-of-certified-products/), tested composition (attention to confidential data), and usage limits.
Each certificate we issue is based on a chain of evidence: test reports for each component, assessment reports, audits, fully digitised.

• Future: From your whitepaper and talks, you emphasize market roadmaps for bioplastics. Which application areas (packaging, textiles, agricultural films, medical) do you expect to scale fastest, and what certification bottlenecks must be removed?

Mr. Dewolfs: The question that arises, and which we ask ourselves every time we receive a request for certification of an “exotic” product, regardless of the materials it is made of, is whether it makes sense for this product to be declared compostable. There are certain product categories for which the answer is obvious: any product that increases the amount of bio-waste sent to composting centres makes sense. These include garden waste collection bags, food packaging and tableware with food residue, etc.
But also products that are not recyclable and will be incinerated, such as multi-layer (packaging) films, or products for which it is not possible to separate the components correctly and which will therefore disrupt the recycling process (like mulching films, …).
That being said, every week we receive requests for certification of products that do not belong in a composting centre or in-home composting. Examples include socks, toys, etc. In case of doubt, an internal advisory committee reviews the request and, if necessary, defines specific evaluation and certification procedures.

Schemes such as OK biobased, which has been running for more than 15 years, and OK renewable, launched in 2025, offer a progressive way to promote non-fossil carbon, even when the sectors are not yet mature.

• Future: Testing infrastructure varies widely by region. What steps would you recommend to accelerate reliable testing capacity globally so manufacturers in emerging markets can get credible certification without prohibitive delays or costs?

Mr. Dewolfs: There are two aspects to this issue: the applicable assessment and testing standards and the competence of laboratories.
I have already addressed the issue of harmonising standards, which is in everyone’s interest.
With regard to the competence of laboratories for our OK compost and OK biodegradable conformity marks, as well as other schemes for which we are recognised (Seedling, REAL), we have a team specifically dedicated to the qualification and quality monitoring of laboratories.
Our main objective is to guarantee the reliability of results, which means eliminating any effects related to the laboratory, geographical location or season. In other words, a test on material X in laboratory Y located in country Z must lead to the same conclusions as the same material tested in another laboratory in another country.
Lead times and prices are the responsibility of the laboratories. We focus on the reliability of results, which includes staff qualifications, protocols, calibrations, etc., and of course, the independence of the laboratory.

• Future: TÜV AUSTRIA often balances scientific rigor with commercial practicality. How do you decide when to tighten certification thresholds versus when to provide transitional/recognition schemes that accelerate adoption?

Mr. Dewolfs: The balance is based on two principles: preserving the credibility of the label and avoiding requirements that unnecessarily hinder innovation.
The thresholds are tightened when consumer confusion or environmental risks are high. For example, we decided not to certify packaging according to OK biodegradable because it could mislead citizens. And we did so well before certain legislations – still tentatively – banned it in turn. We also banned the addition of PFAS before legislation came into force, because protecting the environment and consumers is an absolute priority.
Conversely, schemes such as OK biobased, which has been running for more than 15 years, and OK renewable, launched in 2025, offer a progressive way to promote non-fossil carbon, even when the sectors are not yet mature.

 

• Future: As supply chains adopt more recycled and bio-based feedstocks, quality variability increases. What role should certifiers play in defining acceptance criteria for feedstock variability, especially for food-contact or medical applications?

Mr. Dewolfs: Certifiers must define acceptable ranges based on analytical data: C14 for bio-based materials, spectroscopy for verifying material composition, safety/ecotoxicity tests for sensitive uses.
We have also implemented market surveillance measures and devote a significant portion of our resources to this activity. Products, statements and advertisements are constantly monitored to prevent any abuses. Non-compliance leads to rapid corrective action, suspension of certification, or even permanent withdrawal in cases where non-compliance damages the reputation of our compliance marks, the environment and/or food or medical safety.

• Future: Looking beyond plastics, which emerging materials or technologies (e.g., engineered biopolymers, enzymatic recycling, renewable carbon certification) do you believe will most strongly influence sustainable product design in the next decade — and how should journals like Future Technology prioritize coverage?

Mr. Dewolfs: Please allow me to be more discreet here, as many emerging technologies are currently in the development phase and we are sometimes consulted, not to assist in development, which would be contrary to our certification charter, but to provide an opinion on the compliance with standards or the “certifiability” of certain products.
To improve compostability, the integration of enzymes is one route to explore, but it must still comply with standards. For example, there are ways to make PLA compostable at home, even though it is not by default. This requires the implementation of appropriate validation, evaluation and, above all, market monitoring protocols. This is where certifiers add value. They enable rigorous, scientifically validated communication of innovative solutions through appropriate and reliable logos, without having to reveal all their secrets.
OK renewable certification, on the other hand, is still in its early stages. We are in contact with many major brands that see it as a unique communication opportunity.
This makes sense, for example, for the mouse I am using to write this article. Some components are bio-based, others come from recycling, or even CO2 capture (CCU), and still others from fossil resources. OK renewable allows for clear and documented communication about the renewable share of this mouse.