Plastic Pollution

In recent years plastic pollution has gained global attention due to its harmful effects on our environment, especially our oceans. We often associate plastic pollution with single-use plastics and ocean debris but there is another culprit just beneath our wheels: tire microplastics. In this blog, we will explore the issue of tire microplastic pollution, the involvement of electric vehicles (EVs), and potential solutions to mitigate this environmental threat.

Tire Microplastics

What are they?

Microplastics are tiny plastic particles that are less than 5 millimeters in length. They are a result of the breakdown of larger plastics such as plastic bags and synthetic rubber tires. Tire microplastics are tiny particles that are released into the environment as a result of tire wear from the mechanical abrasion of car tires by road surfaces. These particles are primarily composed of synthetic rubber, a variation on plastic, that leaves behind microplastics that last in the environment for long periods. Other particles left behind by tires include a mixture of embedded asphalt and minerals from the pavement, both of which are harmful to the environment. Recent studies have shown that asphalt is a major contributor to air pollution due to the carbon-based chemicals it releases when the temperature rises. 

Because tires undergo friction during everyday use, the treads are gradually worn down, releasing particles into the air, which eventually find their way into our ecosystem.  They are most commonly found in our marine ecosystem due to wind and waterways, including drainage systems, leading into our oceans.

The size of tire microplastics can vary. Even though they are visible to the naked eye, these particles are small enough to be easily transported by wind or water currents, allowing them to disperse over wide areas. Unfortunately, due to their small size, tire microplastics are often difficult to detect and can not be easily removed from the environment. This makes them a persistent and challenging form of pollution.

Issues They Are Causing: Tire Microplastics Pollution in the Ocean

Wind-blown microplastics are the biggest source of ocean pollution. Within this, tire particles are said to be the biggest contributor to microplastic pollution by contributing a whopping  1 million metric tons of plastic pollution to the environment globally each year. When introduced into waterways they can alter microbial communities and nutrient cycling processes, threatening sensitive aquatic and soil ecosystems. Marine organisms as small as plankton up to marine mammals can mistake these particles for food which leads to bio-accumulation up the food chain.

Pictured above is a mysid shrimp that has ingested microplastic particles from tires. According to Oregon State University, these particles harm the growth and development of these creatures. Credit: Oregon State University 

Not only do these microplastics contribute to aquatic and soil pollution but they also contribute to air pollution. The particles become suspended in the air, and when inhaled, they pose risks to human health, particularly for individuals living in busy cities or working in occupations that are exposed to high levels of traffic.

EV Involvement

In this day and age, a lot of consumers are switching to electric vehicles. While EVs offer numerous environmental benefits, such as reduced greenhouse gas emissions and improved air quality, they are not immune to the issue of tire wear and the release of microplastics. 

EVs are much heavier than conventional internal combustion engine (ICE) vehicles due to their batteries. They use large lithium-ion battery packs to store and provide energy to power the electric motor, which can be quite heavy due to the dense energy storage required for an extended driving range. Their weight accelerates tire wear, which translates to higher microplastic emissions. 

It was recently reported in Norway that 80 percent of new car sales were battery-powered vehicles. As a result, greenhouse gas emissions have fallen 30 percent since 2009 and levels of nitrogen oxide have decreased significantly. But the country now faces a new problem: The city of Oslo’s air has unhealthy levels of microplastics generated partly by the abrasion of tires and asphalt. Experts anticipate that rising EV ownership will continue to increase the amount of microplastics in Norway and the atmosphere at large. 

Of course, there are pros and cons to the adoption of any new technology. Fortunately, the worsening of microplastic pollution caused by EVs does not outweigh the larger environmental benefits of EV adoption. With this said, this doesn’t mean we shouldn’t constantly strive to be better for the planet.

Potential Solutions

Road Infrastructure

One possible solution to decrease the number of tire microplastics in our environment is to invest in well-maintained road infrastructure. Smoother roads with proper maintenance mean less friction and abrasion, allowing tires to last longer and not wear out as quickly. This will reduce the overall amount of microplastic particles that are released and will also allow tires to last longer without needing to be replaced. 

Global Treaty

Another possible solution that has been in the works is a global treaty. As of 2022, 175 nations signed off on a treaty coordinated by the UN to end plastic pollution by 2024. This global agreement, while historic, is expected to be very difficult to enforce. Some are advocating for special provisions to address the problem of microplastics more specifically. Significantly, studies found that microplastics are consumed by humans through food and water and pose long-term health risks to the population. This is a global issue shared by the world, so a treaty must be put into place to combat the problem. But for this treaty to work, tires must be redesigned. 

Redesigning the Tire

Developing innovative tire designs and materials is a promising avenue for reducing microplastic pollution. The task is to create durable tires that last longer and shed fewer microplastics into the environment. A new design in the works called Pureback Nexen Tire is an eco-friendly tire that prevents air pollution caused by microplastics released via tire wear. Even though the tire is still made out of synthetic rubber, each tire possesses a system that separates and discharges the microplastics while driving, storing the debris in a central capsule made of steel. The collected microplastics will then be compressed and deposited at hydrogen charging stations. For participation in this new technology, consumers might be eligible for incentives and rewards as well as getting to be at the forefront of a technological breakthrough working to solve a global issue!

Pictured above is the makeup of the Pureback Nexen Tire. When collecting microplastics it illuminates a bright blue color shown above; when the collection capsule (pictured above) is almost full the tire will illuminate a red color. This tells the driver when to deposit the material at a hydrogen filling station. 

Tire Microplastics Pollution: A Conclusion

Overall, microplastic pollution caused by the wear of tires is an ongoing environmental concern that demands greater attention and action. As electric vehicles gain popularity, it is crucial to address the issue of tire wear and microplastics. Future redesigns and policies must aim to reduce the impact this pollution has on our ecosystem.