Roadside pollution remains a serious health issue despite the cuts in fossil fuels.

Brake dust and tyre rubber particles are the primary concerns, especially with heavier electric vehicles and larger, heavier SUV models.

Small problems and big issues

A new study commissioned by EIT Urban Mobility, Transport for London (TfL) and the Greater London Authority (GLA) warns that non‑exhaust emissions—particles shed from brakes, tyres and road surfaces—now represent the principal source of particulate pollution from road transport.

To curb this under-recognised threat, the report outlines a package of technical, regulatory, and behavioural measures, ranging from adopting wear-resistant components to expanding low-emission zones and lowering urban speed limits.

Particulate matter (PM) remains one of Europe’s gravest environmental health risks.

In 2022, over 96% of Europeans were exposed to PM2.5 concentrations above World Health Organisation (WHO) guidelines.

Exhausting options

While electrification and stricter tailpipe standards have reduced traditional exhaust pollutants, attention has shifted to non-exhaust emissions (NEEs), which in cities such as London, Milan, and Barcelona account for 68–88% of PM10 from road transport and up to 78% of PM2.5.

Brake wear emerges as the largest urban source of NEEs, with more than 40% of particles becoming airborne.

Tyre abrasion also contributes significant particle loads, much of which settles as road dust or contaminates soil and waterways—raising fears of long‑term ecological harm and microplastic accumulation.

The repeated acceleration and braking inherent in city driving further amplifies both forms of pollution.

New regs

Under the forthcoming Euro 7 vehicle standards, limits on brake and tyre wear emissions will be introduced—applying to new vehicles from 2026 and 2028 respectively.

However, the study’s authors argue that waiting for fleet turnover will delay public health benefits. “Speeding up the adoption of wear‑resistant brakes and tyres across all fleets would deliver meaningful improvements sooner,” says Yoann Le Petit, Thought Leadership Manager at EIT Urban Mobility and lead author of the analysis.

He cautions that any widescale transition must be accompanied by rigorous toxicity assessments to avoid unintended consequences.

Alternative transport

Beyond technological fixes, the report highlights the power of shifting away from private car travel.

Modelling indicates that substituting car trips with public transport, walking or cycling can generate up to five times greater reductions in particulate emissions than electrification alone.

When combined—mode shift alongside fleet electrification—the benefits multiply further.

A cost‑benefit simulation for London underscores these findings. The introduction of wear‑resistant brakes and tyres is projected to yield net societal benefits of €235 million (£197.5 million) by 2050, making it the most economically effective intervention considered.

Based on these results, the study calls for a multi‑layered strategy:

  • Local authorities should treat NEEs as a major pollutant source, expanding low‑emission zones, lowering urban speed limits to reduce braking intensity, penalising heavier combustion vehicles (such as SUVs) and maintaining road surfaces to limit abrasion. Investment in public transport and active travel infrastructure must form the backbone of efforts to reduce car dependency.

  • National governments need to enforce Euro 7 standards in full, accelerate research and deployment of low‑wear materials, and support retrofitting of existing vehicles with wear‑resistant components.

  • European institutions should agree on harmonised methodologies for measuring brake, tyre and road wear emissions—a crucial step for building consensus and enabling coordinated policies across member states.

“Only a coordinated approach, spanning regulation, innovation and behavioural change, will be effective in reducing this under‑recognised form of pollution,” Le Petit concludes.

“Cities have the opportunity—and responsibility—to act now.”