Tires cause 2,000 times more pollution than emissions

Dust particles released from tires pollute the air, water and land, and contain a wide range of toxic organic compounds, including carcinogens. Analysts also warn that tire pollution could quickly become a major problem for regulators.

Air pollution can lead to millions of premature deaths globally each year. In developed countries, the requirement for better filters means that soot in the exhaust is also much lower on new models, and in Europe is often much lower than the permissible limit. However, the increased weight means more dust particles from the tires are released into the air.

Experiments conducted by Emissions Analytics (EA, UK) also show that tires produce more than 1,000 kg of ultra-fine particles with every kilometer the vehicle passes, ie particles smaller than 23 nm in size. Ultra-fine particles also radiate from the exhaust pipe and are especially concerned with human health because the size of the supercar makes it possible for them to enter the organs through the blood. Particles smaller than 23 nm are difficult to measure.

EA’s Nick Molden said the baseline estimate of fine particulate pollution from tires prompted them to do the study. “We’re baffled about the amount of material being released into the environment – 300,000 tonnes of rubber tires in the UK and US, from cars and vans alone each year.”

There are currently no regulations for tire wear rates and only a small number of regulations for chemicals in tires. EA has identified chemicals in 250 different types of tires, which are often made from synthetic rubber, extracted from crude oil.

The wear rate of tires of different brands varies widely, and the harmful chemicals are equally diverse.

Tire wear tests were carried out with 14 different tire brands, respectively mounted on the same Mercedes C-class vehicle and normally on public roads. Microscales are used to measure tire weight loss and a sampling system helps to collect dust particles behind the tire as the vehicle passes for weighing, counting and measuring particles, up to 6 nm in size.

Emissions from vehicles are also measured with 4 petrol-powered SUV models – the most popular new model today, with models from the 2019-2020 model year.

Old tires produce 36 mg of particles per kilometer, 1,850 times higher than the 0.02 mg/km average for emissions. In particular, the style of driving “speeding and overtaking” also causes dust particle pollution to reach 5,760 mg/km.

From the tires, there are also more smaller nuts than larger ones. That means more microscopic particles will be released into the air and contribute to pollution, even though they only account for 11% of the total weight of particles emitted from the tire. Even so, tires still produce hundreds of times more dust particles into the air than the amount of soot of the same weight from the exhaust.

The average weight of all cars today has also increased. Controversy is often about pure electric cars (BEVs) – which are heavier than cars with internal combustion engines and have higher torque (or rotational force) – can produce more tires. Molden says that can depend on driving style, with calm drivers driving electric vehicles also producing less dust particles than gas-car drivers who drive recklessly. But on average, dust particles from electric vehicle tires can be slightly higher.

Dr James Tate, of the University of Leeds’ Transport Research Institute (UK), says that the results from the tire tests are reliable. “But it’s very important to note that all-electric cars are becoming lighter. By the end of 2024-2025, it is expected that BEVs and cars with internal combustion engines will have similar weight. Only high-end BEV models are expected. , the larger size with the larger battery pack is heavier”.

Another recent study also suggests that tire dust is a major source of microplastic pollution in the ocean. A particular chemical used in tires has been linked to salmon deaths in the US, prompting the state of California to propose new regulations this month.

America – England (follow Guardian)