While the term "filthy rich" has always had a positive connotation, a recent study conducted by NYU researchers casts an altogether different light on those words.
In what is being called the first comprehensive study of the DNA on dollar bills, researchers at New York University's Dirty Money Project have discovered our currency is a hotbed for the exchange of hundreds of different kinds of bacteria as we pass these bills from person to person.
As part of the project, NYU researchers analyzed the genetic material on $1 bills and identified 3,000 types of bacteria in all. The high number of bacteria discovered was many times higher than ever discovered in the past, when samples were typically studied under a microscope. Despite the large number of bacteria discovered, the NYU team of researchers could only identify about 20 percent of the nonhuman DNA they found on the currency because so many of the microorganisms haven't yet been cataloged in genetic data banks.
Among the more abundant species researchers discovered was one that causes common skin problems in people, specifically acne. Several others were linked to health issues such as food poisoning, gastric ulcers, pneumonia and staph infections. Some also carried genes responsible for antibiotic resistance.
"It was quite amazing to us," said Jane Carlton, director of genome sequencing at NYU's Center for Genomics and Systems Biology where the research was performed. "We actually found that microbes grow on money."
The research has confirmed what many hygienists have felt all along - the passing around of all paper currency all over the world could be a major source of contagion.
While the fear of counterfeiting will always be high on the list of concerns for currency experts such as central banks and state treasuries, many are now beginning to put microbiology on the list of concerns as well. Often likening a body-temperature wallet to a petri dish, governments around the world are looking into ways to combat this problem.
Additional research on this subject was recently conducted in the medical microbiology lab of Canisius Wilhelmina Ziekenhuis which also confirmed that the type of banknote paper might be an additional variable to consider in efforts to deal with this issue.
In this study the research sought to ascertain the survival status of bacteria including Staphylococcus aureus, Escherichia coli, and Vancomycin-Resistant Enterococci on banknotes from different countries and the transmission of bacteria to people who come in contact with these specific banknotes. Among the conclusions discovered was the survival rate for the aforementioned bacteria was highest on the Romanian Leu currency after both three and six hours of drying.
