Your mother was right: Steer clear of dirty money
"Don't put that money in your mouth! You never know where it's been!"
While your mother was likely more concerned about germs on coins, she might have been on to something.
A study published by Swiss researchers a couple of years ago suggested that an infectious virus can survive for three days on bank notes. Sounds like a great argument for using debit cards, particularly when you consider that dingy dollars might affect your behaviour as well.
In fact, handling dollar bills that aren’t crisp and clean could actually tilt you towards the dark side, explains Kevin Lewis in the Boston Globe.