Syllabus:

GS3: Conservation, environmental pollution and degradation, environmental impact assessment.

Context: 

A recent study, published in the Soft Matter Journal, has shown that Electric Vehicles (EVs) on account of their greater weight, experience higher wear and tear in their tyres compared to conventional vehicles, and release substantially larger numbers of small plastic particles in the atmosphere.

Mechanism of Tyre Degradation

• The disintegration of automobile tyres results in the release of small rubber particles that are air pollutants.

Tyre wear produces particles of various sizes:

• Small particles: 1–10 micrometres (remain airborne and contribute to air pollution)
• Large particles: >100 micrometres (usually settle due to gravity)
• Intermediate particles exist but are fewer.

Factors Affecting Tyre Wear

• Vehicle weight and speed influence the amount and size of plastic particles released.
• Heavier, faster-moving vehicles release a higher proportion of smaller, airborne particles.

Processes Behind Particle Generation

• EVs are able to accelerate rapidly as a result it leads to additional stress on the tyres due to increased friction and heat generation. 
• This leads to greater degree of Primary fragmentation (e.g., sudden braking, potholes) which produces mainly large amount of smaller plastic particles.

Global EV Trends

EVs account for:

• Only 2% of the current global vehicle stock
• Nearly 20% of new car sales in 2023 (IEA)

India:

• EVs made up 2.5% of car sales in 2024
• Government aims for 30% EVs car sales by 2030

China:

• EVs constituted almost 50% of new car sales last year.

Policy and Technological Recommendations

• Current air quality norms target PM2.5 and PM10 but tyre particles are often smaller than PM2.5, escaping regulation.
• Regulations related to air quality will likely need to be expanded due to the increasing prevalence of electric vehicles (EVs) and the growing awareness of tyre fragments as a source of pollution.
• The researchers have also suggested possible technological fixes – such as the possibility of capturing the small tyre fragments at the time of their release, preventing them from getting into the atmosphere.

Therefore, Tyre manufacturers must: 

• Develop more durable tyres suited for heavier EVs.
• EVs should invest in R&D for sustainable tyre materials production.