After public consultation: majority of comments against classification of silica
The 60-day public consultation period within the current substance evaluation (CLH) process for synthetic amorphous silica (SAS) resulted in 71 comments from silica producers, trade associations, downstream users and authorities. A vast majority argued against the proposed classification of synthetic amorphous silica as STOT RE 1 within the European Union.
The dossier-submitting authority received 60 comments from EU member states, 8 comments from the United States and 3 from Japan. The commentators included prominent voices from the industry. In a total of 66 comments, they provided valid and well-founded arguments against the classification of synthetic amorphous silica.
The compiled comments and non-confidential attachments are also published on this ECHA website
After a thorough assessment of the relevant data and information, RAC forms its opinion on the proposed CLH. RAC confirmed its preliminary opinion on the proposed CLH classification from November 2025, remaining unimpressed by submissions from industry and academia.
Evonik’s position on the classification of silica as STOT RE 1
We reject a classification of synthetic amorphous silica (SAS) as STOT RE 1 because we are convinced that synthetic amorphous silica is safe for producers, processors and consumers. Furthermore, we are convinced that this hazard class for SAS is neither scientifically justified nor in terms of health policy.
The proposed STOT RE 1, H372 classification is based on inhalation tests that led to isolated cases of inflammatory processes in lung tissue. But the concentration and duration of exposure during these tests did not correspond to the real conditions when producing and processing SAS.
At no point in the value chain do people come into contact with dust of synthetic amorphous silica in hazardous concentrations.
Our main arguments against the classification of SAS:
- Synthetic amorphous silica is safe in compliance with the applicable occupational health and safety regulations – during production, processing, transport and storage. In the processed product, silica occurs in bound form only and is safe for consumers.
- In most downstream user sectors, there is no equivalent alternative to silica that offers the same level of quality and performance. This would invariably be a case of regrettable substitution.
- If processors were to dispense with silica, this would massively impair the quality and properties of countless high-tech and everyday products. Important EU export goods would no longer meet their previous quality standards and would be harder to sell globally. Some products could even disappear from the market.
