A ground-breaking pilot in the Dutch city of Doetinchem has demonstrated that polluted clay can be transformed into safe, functional bricks. The project, led by innovative startup Claybens, turned 20 cubic metres of PFAS-contaminated clay into 50,000 clean bricks. These bricks will soon be used in a local housing project near the clay’s original site.
PFAS (per- and polyfluoroalkyl substances) are synthetic chemicals found in products like firefighting foam, non-stick pans, and rain-resistant clothing. They are known for their durability, which makes them useful in manufacturing but harmful in nature. Once in the soil, PFAS do not break down and can pose long-term risks to human health and the environment.
In most cases, contaminated clay is excavated and stored in landfills. This method is costly and creates no lasting solution. In contrast, Claybens developed a process that eliminates the PFAS. By firing the clay at 1000–1200°C for several hours, the harmful compounds break down completely. Independent lab tests confirmed that the resulting bricks are PFAS-free and meet all safety and construction standards.
This pilot marks the first time that PFAS-contaminated clay has been used at such a large scale in brickmaking. Claybens led the project and coordinated partners across the value chain. Brick manufacturer Caprice handled production, while Delgromij prepared the clay mix. The municipality of Doetinchem supplied the contaminated clay, and the province of Gelderland and the Dutch Ministry of Infrastructure provided funding. The Arnhem Environmental Service (ODRA) approved the pilot and ensured all safety conditions were met.
Throughout the production process, environmental emissions were monitored closely. No harmful substances escaped into the air, and the pilot followed all safety and health regulations. The project showed that this method can be carried out safely and effectively, even at industrial scale.
For architects, product designers, and others in the built environment, this innovation offers real circular value. Instead of treating contaminated clay as waste, the process turns it into a high-quality building product. It also avoids further landfill use and reduces the need for virgin clay extraction.
The bricks from the pilot will soon become part of a housing development near the excavation site, completing a local and circular material loop. As Claybens prepares for scaled-up production, this method could offer designers new pathways for combining environmental remediation with sustainable material sourcing.
Source & Photos: Claybens / Provincie Gelderland