Is your car dirtier than a toilet?

UK study suggests the probability is high.

EATING in your car might turn out to be … well, a crappy decision.

A new study out of the United Kingdom has found vehicles can be dirtier than the average toilet.

The study commissioned by a blog called Scrap Car Comparison was conducted by researchers from Aston University’s School of Biosciences and saw them take samples from two toilets and five vehicles, one just two years old.

The results are a bit stomach turning as every vehicle in the study contained fecal bacteria.

Somewhat surprisingly, the highest levels were found in the trunk and researchers noted this is the same area where most people transport their groceries.

The full findings are discussed in the attached video Dr Jonathan Cox, a senior lecturer in microbiology at Acton Uni who led the research.

For each vehicle, samples were taken in the six key locations of a car’s interior, using a sterile cotton bud swab, hydrated with phosphate buffered saline. Each swab was then spread onto inoculated agar plates and incubated at 37 degrees Celcius for 24 hours in order to identify any bacterial growth.

The areas with most bacteria are the boot (1425 bacteria identified), the driver’s seat (649 bacteria identified), the gearstick (407), the back seat (323), the dashboard (317) and the steering wheel bacteria (146).

The boot count significantly exceeded the bacterial contamination levels of an average toilet, researchers say.

Said Dr Cox: “The boot is often where we put our groceries when we go to the supermarket – and with a reduction in the use of carrier bags, there’s a much greater potential of throwing loose items into the boot of a car to travel home.

“With this in mind, we should be mindful of reducing the risk of this food by making sure to sufficiently clean any fruit, vegetables or other produce before eating it.”

The steering wheel showing a very low level of bacterial contamination was attributed to people taking care to sanitise because of coronavirus. 

“Due to increased sanitizer use since the COVID-19 pandemic, the driver contact surfaces generally didn’t have the level of bacteria that we were expecting, meaning that areas such as the steering wheel were not as contaminated as they might have been a few years back.” 

The results also showed that in general, bacterial contamination correlated with the age of the vehicle.

The older cars sampled for the study exhibited higher bacteria loads than those that had been on the road for a shorter amount of time.

As grubby as vehicle interiors can be, Dr Cox makes this point: “…people don’t get sick every time they get in the car. We don’t need to be overly concerned; we just should be mindful that not all dirt is visible for us to see. 

“This study has shown that people could definitely make more of an effort to keep their car clean. Ultimately, it’s about mitigating the risk of getting sick.

 “We are unlikely to eat food in the boot of our car, but often consume food in the driver’s seat. Cleaning our hands before we eat in that environment is a good idea, and knowing where microorganisms may be residing can help us to think more about our habits when we drive – I would certainly think twice before picking up a dropped wine gum and eating it assuming it’s fine!”

For the full research see: https://www.scrapcarcomparison.co.uk/blog/the-dirtiest-areas-of-cars/