The study comes from a rental car blog, which also found most people only clean their cars once per year. Guys, that just isn't often enough.
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A new survey has shed some light on how disgusting the average steering wheel is, suggesting it's four times dirtier than a public toilet seat.

With 629 colony-forming units (CFU) of bacteria per square centimetre, it's also six times filthier than an average smartphone screen, and twice as bad as public elevator buttons.

According to the research, 12 per cent of Americans never clean the inside of their cars, in spite of the potential for bacteria growth.

Some of those germs are unavoidable, but a few common dirty habits compound the filth. Eating behind the wheel, something 20 per cent of American drivers do weekly, creates a veritable army of bacteria.

"That french fry you dropped in between the seat and centre console or your child’s spilled milk on the backseat creates a breeding ground for bacteria," the study says.

"Keep the windows up and park in the hot sun, and these food spills begin to multiply and spread throughout the vehicle."

The filthiness continues when it comes time to refuel, with the research revealing a pump handle is (brace yourself, folks) a whopping 6428 times dirtier than elevator buttons and 11,835 times worse than a public toilet seat.

Buttons on American pumps – which tend to have one pump delivering different fuels, forcing drivers to instead choose their 'gas' before picking up the handle – returned 2.6 million CFU, or 600,000 more than even the pump handle.

So, how can you avoid the germs and nastiness? For one, clean your car. The study suggests sanitising the things you touch, changing your air conditioning filter, cleaning the keys, and vacuuming the upholstery.

It also advises drivers to wash their hands after refuelling.