Never put your money where your mouth is! At least, in the literal sense.
We have all know money is dirty. This shouldn’t be a surprise because it gets passed around from person to person fairly quickly. The dollar you have in your wallet has probably traveled a great distance and handled by a lot of people. But how dirty is money? And should we be worried?

Researchers from New York University’s Dirty Money Project answered these questions and found some surprising results. They analyzed the genetic materials on $1 bills and identified 3,000 different types of bacteria! The most common type is a strain of bacteria is the ones that cause acne. Other germs that topped the list include mouth and vaginal microbes, and those that cause skin infections, food-borne illnesses, gastric ulcers, pneumonia, and antibiotic-resistant infections. Anthrax was also found, although the dose is too insignificant to cause any harm.
Money here in the US is also dirtier than money in other countries. This is because US bills are made from cotton-based paper, which is absorbent and makes it easier for germs to grow. In contrast, other countries have polymer-based money, which is more ideal to prevent bacteria from growing.
Other studies on the subject also found some other interesting things on money. A 2002 report published in the Southern Medical Journal found fecal matter on 94% of bills, and concluded that paper money can carry more germs than a toilet! They also found that about 80% of bills carry germs that can make you sick, and 7% causes serious illnesses. And a 2009 study at the University of Massachusetts concluded that 90% of paper money has traces of cocaine.
So what does this mean? Jane Carlton, the lead researcher of the Dirty Money Project, suggests washing your hands after handling money. After all, if money has about as many germs as a toilet, washing your hands may be the best solution. Your credit and debit cards are also more sanitary options.
Justin Chu is the Information and Communication Program Assistant at UNC Student Wellness and a Master of Public Health graduate student with a focus in Health Behavior at UNC Gillings School of Global Public Health. He previously worked as a nutritionist in the clinical, community, and commercial settings after earning his bachelor’s in Clinical Nutrition at the University of California at Davis.