You might have already heard what one can find on paper money when looking at it under the microscope and its gross (cocaine for example) but it is not only what is sticking to it, sometimes the feel is nasty and the smell even worse. So if you want to neutralize some of the nasty, choose your favourite essential oil or two, put one or two drops on a strip of paper that you put between your paper money so that it can take up the scent and the next time you hand some money to the cashier they will be really surprised about your aromatic money! 
Be well and see you soon