Money
These days it would be better to use a debit or credit card for most purchases, however, sometimes you just need to handle cash. When you do, be sure to wash your hands as soon as possible. Researchers tested $1 bills from a New York City bank and found hundreds of microorganisms, including oral and vaginal bacteria, and DNA from pets and viruses.
Similar research has shown that in some cases, cash and coins contain pathogens like E. coli and salmonella. It doesn’t help that money circulates for a while—$100 bills can circulate for as long as 15 years, according to the Federal Reserve. This also makes your wallet filled with germs.
