Filthy research finds car interiors more dirty than toilet seats

Talk about a stinker of a story, results from a British university study says your car’s interior could be dirtier than the average toilet.

Aston University in Birmingham took bacterial swabs from five cars of varying ages to determine which areas were the least hygienic. These ranged from a 17-year-old Peugeot 307-SW right down to a Peugeot 308 built just two years ago.

Swabs from six locations inside each car were then left to incubate for 24 hours before analysing bacterial growth.

While the study might resemble an intermediate school science fair project, the results are actually rather intriguing.

The boot was comfortably ranked the number one area of the car that has the most bacteria. The place where most of us tend to leave our groceries when travelling to and from the supermarket collect 1425 microbes in a single swab.

Second-best, or worse, was the driver’s seat, followed by those places where you’re more likely to touch, such as the gearstick and steering wheel. In fact, the steering wheel had a relatively low bacterial count: a result those conducting the study believe is down to a recent surge in sanitising our hands.

“Due to increased sanitiser use since the Covid-19 pandemic, driver contact surfaces generally didn’t have the level of bacteria that we were expecting,” Dr Jonathon Cox said.

Even so, the likes of the boot, driver’s seat and dashboard were more contaminated than a pair of public toilets tested earlier. But there isn’t too much to fear.

According to Cox, despite the filthy results of his team’s research, the chances of getting sick simply by driving your car are meagre. But he insists we should continue cleaning our vehicles regularly, and not just the exterior.

“We often see mud splashes which remind us to drive to the nearest car wash, but we don’t see the bacteria building up in our vehicles, and we should be cleaning the inside as much as the exterior.

“Knowing the bacteria that can build up in our cars can be really useful in cleaning our cars properly and regularly, and reducing any risks.”

Areas of our cars with the most bacteria:

1. Boot – 1,425 bacteria identified
2. Driver’s seat – 649 bacteria identified
3. Gearstick – 407 bacteria identified
4. Back seat – 323 bacteria identified
5. Dashboard – 317 bacteria identified
6. Steering wheel – 146 bacteria identified