Proposed EU silica classification raises concerns for tire industry

Brussels – Europe's tire makers have warned that a proposed EU classification of synthetic amorphous silica (SAS) as a hazardous substance could have far-reaching consequences for the industry.

In a 2 July position paper, Tyres Europe said SAS plays a critical role in delivering the combination of low rolling resistance, wet grip and durability known as the tire industry's "magic triangle", while supporting EU climate and mobility objectives.

The paper was issued as synthetic amorphous silica comes under consideration for harmonised classification as ‘specific target organ toxicity’ (repeated exposure category 1), with the respiratory tract identified as the target organ.

According to the industry association, such a classification would automatically designate SAS as a "substance of concern" under the EU's Ecodesign for Sustainable Products Regulation (ESPR): triggering product information requirements and potentially influencing product-design.

"While the classification would not constitute a restriction on use, this will increase the pressure to phase out SAS at the design stage, not merely to manage exposure," the position paper stated.

The principal regulatory risk, it added, "would not arise from demonstrated exposure during use, but from the way in which hazard classification can influence design acceptability and product-policy screening criteria."

This, said Tyres Europe, could create "disproportionate pressure to replace a technically important material even in the absence of a functionally equivalent alternative capable of delivering the same balance of performance, safety, and sustainability outcomes."

The EU tire industry consumes around one-third of all synthetic amorphous silica produced in Europe, while tires account for more than half of demand for precipitated silica – the main SAS grade used in tire compounds.

Describing SAS as an "essential functional material", the paper said it has "a long-established history of safe use" and remains "chemically and physically integrated" within the cured rubber matrix throughout a tire's service life.

Tyres Europe also cited epidemiological studies indicating that SAS has a "low toxicity profile" and notes that the material is supplied as "low dust micropearls or granulates" to minimise worker exposure during handling.

Beyond safety, the paper said silica-filled tire compounds can reduce rolling resistance, improve wet grip and maintain wear performance simultaneously.

Furthermore, major tire manufacturers report that SAS-containing tires can reduce CO2 emissions by up to 8%, while also extending tire life and reducing tire wear particle emissions.

Concluded the paper: "Any regulatory measure affecting SAS should be grounded in a robust evaluation and consideration of its properties, an assessment of exposure conditions within longstanding industrial uses, and an evaluation of socio-economic implications for downstream industries.”

Regulatory action that fails to consider these factors, it warned, "could generate unintended consequences for the resilience of the European industrial value-chain, including for the tire industry."