Talk about dirty money—a lot of unsavory things come with our money when it changes hands.
A new study shows us how money keeps a kind of record of our activities. Now, we know that the world we live in is dirty, in a sense. We share our space with a lot of microbes, and perhaps it's best if we don't really think about that. After all, thinking about all those microbes and where they are can be a little freaky. However, it's interesting to see what kind of mark we make on our money.
Our money takes a bit of whatever it passes through—pockets, parking meters, vending machines. The researchers call this “molecular echoes”. These molecular echoes reveal interesting things about ourselves, other people, what we put our money through, and what we might potentially get when we get money from the ATM, or change from the cleaners.
Researchers found different bacteria and traces of different substances on dollar bills making the rounds in New York City. They found that these bills carry bacteria that reside in our mouths and bacteria that cause acne. They also found DNA from household pets and traces of specific kinds of foods. Surprisingly, the researchers also found that about 80% of the bills they tested had traces of cocaine on them. Traces of other drugs like heroin, methamphetamine, morphine, and amphetamine also make an appearance, though at a lesser frequency.
These findings are of course interesting, but what other purpose do they serve? Studies such as these can help researchers discern patterns in how diseases spread. Before anyone panics, it's important to note that most of the microbes that the researchers identified on the bills do not cause disease. It's also important to note that studies have found that the spread of disease through money is rare.
This doesn't mean, however, that we can be careless with how we handle both our money and food. Studies have found that Salmonella and E.coli bacteria can live on coins as well as on ATMs. The researchers say that these kinds of exposures to microbes are harmless, but it's still prudent to be hygienic when handling money. After all, researchers aren't sure about the extent to which money can spread disease.
Can dirty money become clean again? Fortunately, yes. Scientists are already hard at work on figuring out ways to clean money as it changes hands. Carbon dioxide at a certain temperature can also strip oils, dirt, and microbes off of these bills.
Of course, we still don't know how clean the money we're currently handling is. There may also be no way to know whether or not the money we receive has already undergone some cleaning process. Thus, old wisdom will probably still prevail. It may be best to consider any money as dirty money. Though researchers say that money probably won't spread disease, it's better to be safe than sorry. Make sure to remember your mother's sage advice: always wash your hands after touching money.
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