The new £5 notes are more hygienic than other notes, according to research undertaken in Shropshire in which cash was literally laundered.
Academics at Harper Adams University have spent the past two years researching how clean money is.
Using a series of different experiments, they tested how much bacteria was carried on notes from around the world, and how long it stayed there.
Professor Frank Vriesekoop, senior lecturer in food science at the university near Newport, looked at the amount of bacteria on bank notes in a whole range of countries.
He said: “We found two main things out of that, one was that the material the bank notes are made out of had a significant difference on the number of bacteria we could find and the other thing was that the more prosperous a country was the less bacteria you could find on them.”
They found plastic notes, like the new £5, had significantly less bacteria on them.
They also completed tests where they ‘washed’ money, to see how long bacteria could stay on different notes.
Professor Vriesekoop added: “We took bacteria from people’s hands and placed them on plastic bank notes and then compared them to the cotton bank notes and the other types of bank notes that are used around in the world to see how long do they stay alive.
“Actually we found out bacteria doesn’t stay alive for very long at all on the plastic bank notes.
“Another thing we looked at was how easy it was for the bacteria to be removed from the bank notes or, to turn that argument on its head, how well do they stick to the bank notes and we used a method where we washed bank notes and measured every single time how many bacteria were left after washing.
Professor Vriesekoop said they were inspired to conduct the research after students asked him whether the issue was something to be concerned about, and he couldn’t find any significant or relevant information on it.
He concluded that as a “rule of thumb” plastic money is more hygienic and carries less bacteria on it that older notes.
The new £5 notes have been surrounded by controversy because of the use of animal fat in their production.
Hindu temples have banned the new note after it was revealed they contain tallow, which comes from beef or mutton fat.
As well as upsetting vegetarians and vegans, the news also caused concern among members of the Hindu community, who view cows as sacred.
The Bank of England says it is working to find a solution to the problem.Subscribe to our Newsletter