WHAT'S IN YOUT WALLET?

A cash-stuffed wallet may as well be a petri dish. A new genetic analysis reveals that a U.S. $1 bill can be home to more than 3,000 types of bacteria. “We actually found that microbes grew on money,” Jane Carlton, director of genome sequencing at New York University tells The Wall Street Journal. “It was quite amazing to us.” The bacteria—including some found in fecal matter—are picked up from the dirty hands of people, with microbes feeding on the waxy residue of skin and oils that collects on bills in circulation. It’s still unclear if money’s material—a cotton-linen blend—further encourages bacterial growth. Researchers examined 80 dollar bills from a Manhattan bank, finding a total of 1.2 billion DNA segments. About half of the DNA was human, and only about 20 percent of the nonhuman material could be identified. The most common microbes were those that cause acne, but bacteria linked to gastric ulcers, pneumonia, food poisoning, and staph infections were also found, as well as some responsible for antibiotic resistance. Though money’s role in actually causing disease is unknown, the findings may help health scientists identify potential disease outbreaks before they spread too far.