Did you know that cars are germ magnets? 

Perhaps it's time to book our new Ozone disinfectant service?

Hygiene has never been more heavily featured in the news, and if anything, 2020 has put hand washing and cleanliness at the forefront of our minds.

But while a lot of the news has centred around keeping our homes clean, what of our cars?

At ATS, we take vehicle cleanliness seriously, which is why we have introduced a new Ozone disinfectant service that neutralises viruses and bacteria in your vehicle. Alongside this, we also offer an air conditioning service and anti-bacterial clean.

But did you know that UK cars can be 16 times more contaminated than a toilet seat?

This, according to Professor John Ward from the Department of Biochemical Engineering at University College London. “Studies have found that on the average toilet seat there are 50 bacteria per square inch. The most heavily contaminated parts of a car number between 2,000 and 4,000.” 

We invited Prof. Ward to our ATS garage in Brixton Hill to see what he’d find. Here, the professor and his team were given eleven cars owned by the general public to inspect, with the same six areas of each car under inspection.

The places in question? 

The humble cup holder, the dashboard buttons, steering wheel, gear stick, seat belt catch, and finally, the door handle. 
Swabs were placed in agar plates and incubated for 4 days at 30oC. Photos were taken of the bacteria growing before the plates were incubated for 3 more days at the same temperature. 

In the report to follow, we identify what was found – as well as the potential harm these bacteria pose.

Germiest areas of the car (worst to best) 

Eleven cars were lined up, with the same six areas of each car under examination. In the rankings below – worst to best – 100% prevalence means bacterium was found in each car.

germ areas in car
germ areas in car

Beware “nooks and crannies”, Prof. Ward notes, as this is where tiny bits of debris and skin flakes accumulate. By contrast, the gear stick and steering wheel fare well, in part because their smooth and shiny surfaces retain less bacteria.

“As for the cup holder – it’s exactly that… a holder with a shape designed to hold and retain the cup… as well as any other small bits of debris. With some little bits of liquid, this provides quite a good little environmental niche for bacteria to be trapped and grow.”

The upshot? Clean yours today. 

What types of bacteria live in our cars?

With eleven cars under inspection, here’s the bacteria that was found. 

type of germs found in cars
type of germs found in cars

Bacteria prevalence – most to least


Of the bacteria types found, which were the most common? 

Bacteria Prevalence in cars
Bacteria Prevalence in cars

In summary, Prof. Ward and his team discovered skin bacteria throughout all the cars. Alongside this, sinusitis-causing Staphylococcus aureus was present in the cup holders and on the seat belt catch. Soil bacteria was discovered on drivers’ door handles and dashboard buttons, and mucus residue on places like the steering wheel.

The nature of the study meant that harmful bacteria like Burkholderia and Prevotella didn’t show up on the agar plates, but Prof. Ward believes these “commensal microbiomes” are likely present and can be harmful to people with heart problems and pacemakers.

Bacteria prevalence vs potential harm

Our graph illustrates the potential harm – and prevalence – of the bacteria found. High prevalence and a high degree of harm = greater risk. 

graph showing bacteria amounts
graph showing bacteria amounts

How do we keep our cars clean?


Tips and tricks to keep the inside of your car bacteria-free. 

how to keep your can clean
how to keep your can clean

Prof. Ward’s advice is clear: “clean your car as you would your home.” Wipe down surfaces, and take particular precautions if you have children, as they can pick up viruses you might not encounter otherwise. 

Ready to start spring cleaning? Take a look at our vehicle disinfectant treatment and our air conditioning service and anti-bacterial clean, which will keep your cabin cool and, in conjunction with our steps above, help you to keep your cabin as germ-free as possible. 

While you’re at it, be sure to check that your car is in good working condition. Our helpful car service checklist gives you the lowdown on what needs checking, and you can book a full car service through us in a matter of clicks. 

dishes containing germs found in swabbed cars
dishes containing germs found in swabbed cars

Professor John Ward studied Biochemistry at the University of Bristol and graduated in 1975. After gaining his doctorate, he moved to the Biochemistry Department at University College London (UCL) and ran a course in Applied Molecular Biology and Biotechnology for 17 years. Today, Prof Ward is a Professor of Synthetic Biology for Bioprocessing at UCL. 

Disclaimer: All data was collected by Professor Ward and his students on September 17th2020 from eleven vehicles at an ATS testing centre in Brixton, United Kingdom.