There's a new reason for laundering money. Dollar bills support a rich flora of bacteria, some of them infectious, say research physicians Theodore W. Pope and Peter T. Ender of the Medical Center of Wright-Patterson Air Force Base in Ohio.
They worked with Michael A. Koroscil at Beavercreek (Ohio) High School, who originated the idea for a science-fair project. The group counted the bacteria living on 68 dollar bills collected from people in line at a high school sporting event and a grocery store.
The researchers incubated each bill in nutrient broth for up to a day and then grew any bacteria in culture dishes to identify them. More than half the bills hosted bacteria that commonly infect people in hospitals or those who have depressed immune systems, the team reported. Five of the bills contained a bacterium that can sicken healthy people, either Klebsiella pneumonia or Staphylococcus aureus. The researchers identified a total of 93 different types