The average car has more than 500 colonies of germs and moulds according to new research.

In the study of five stereotypical motorists vehicles by microbiologists at car care company, Comma, dog owners accounted for at least 766 germ colonies giving them the title of the most bacteria ridden cars in the country.

Twenty-something ‘boy racers’ came in second with more than 541 colonies, followed by female motorists with 468. Despite the everyday presence of children and dribbling babies, the family car (264) came fourth with the more mature motorist propping up the table with 226 colonies found.

Comma found that the driver’s seat of the twenty-something male driver contained 192 colonies of germs. Comparatively, that was more than five times as many as were discovered on the seat of a female’s car, and 20 times more than a mature motorist.

Comma found that dog-owners boots were so infested with germs that scientists could no longer accurately count the number of colonies present.

The case was the same for the driving footwell, which was the most condensely-populated area of all the cars tested. Comma’s microbiologist gave up counting on three of the five cars tested (dog owner, boy racer and twenty-something girl).

Staphylococcus, a species most commonly associated with nose-picking, was found in abundance on the steering wheel and driver’s seat. The Bacillus germ, normally found in soil and stagnant water, was found in plentiful numbers in samples taken from the boot and footwell.

"Although the microbes found came from the skin of the driver and passengers, and are relatively harmless, you may not want to spend your journey with all those germs," says Comma microbiologist, Suzanne Stubbs.

"Some of us neglect cleaning our cars in a way we never would with our homes, so the high results were not so surprising."