A new study reveals that millions of drivers could be being poisoned by the air in their car. The claims come after researchers from a company specialising in motoring pollution tested 11 popular cars.
We’ve already revealed the bacteria living in car air-con. Now a study has found that some new models do little to protect occupants from dirty air coming in via filters in the ventilation system. Nick Molden, whose company Emissions Analytics was behind the report, said: “Our research suggests many vehicles are a risk to their drivers’ health.”
Which cars did badly?
According to Emissions Analytics, the funky Toyota C-HR small SUV screens its occupants from just 1 per cent of poisonous particles. The Volkswagen Polo, the UK’s seventh best-selling car halfway through 2018, snared 35 per cent of particles. And Britain’s best seller, the Ford Fiesta removed 40 per cent of pollutants. Disappointingly, filters in the £29,000 Jaguar E-PACE stopped just 43 per cent of pollution. The Volkswagen Touran, a people carrier bought mainly by families, kept out 59 per cent.
Which cars did well?
The best of the affordable cars was the Vauxhall Astra. That blocked 83 per cent of nasties. The car that proved best overall in the test was the Mercedes-Benz E-Class whose prices start at £36,000.
What does the cabin air filter do?
Putting the effectiveness of individual filters aside for a second, most work on the same principle. The ventilation system sucks air in from the outside. This then goes through a filter before entering the cabin. Traditionally, these filters are made from pleated paper, sometimes with cotton blended into them. The idea is that they catch noxious particles from exhaust fumes, and irritants from pollen and other dust letting us breathe clean air.
Do we need cabin air filters?
In a word, yes. In some roadside samples, Emissions Analytics found 57,000 particles per cubic centimetre (cc) of air. The average person inhales 55cc per breath meaning they take in more than 3m particles every time they breathe in. Even if the car removes half of those, that’s still more than 1.5m particles per breath.
These particles are hazardous because as well as entering our lungs, they can enter the blood stream too. They are considered responsible for some heart disease, strokes and cancers. The World Health Organisation claims that every year, three million people die from breathing polluted air.
Do cabin air filters need changing?
As we can see, in certain circumstances cabin air filters have a lot of work to do. And over time they get clogged with the stuff they’re keeping out of the cabin. They should be changed on a relatively regular basis. Exactly when this should happen varies from car to car.
How often they need changing also depends on the kind of miles you drive. Urban drivers commuting in rush hour will need to replace their filters more frequently that those who don’t drive in congested conditions. Usually car owners should change filters between 12,000 and 25,000 miles.
Is there no law governing cabin air filters?
Despite there being an increasing furore over the poor quality of our air, particularly in UK cities, there is no legislation governing the cabin filters in cars. Nick Molden added: “There is little data to tell consumers what they are buying. If you have kids with asthma or other conditions you cannot tell if the car you are buying will protect them.”
Some car makers do claim they purify the air in their motors. Volvo has what it calls CleanZone technology that it claims filters out most pollution. Meanwhile innovative US firm Tesla uses High-Efficiency Particulate Air (HEPA) air filters in its latest models. These filters have to work to a certain level of efficiency prescribed by the US government. Tesla claims they’re so effective at keeping poisons out of its cars, it’s christened its ventilation system Bioweapon Defense Mode.