February 4 of this year was a momentous day for numismatists as the Canadian Mint officially stopped distribution of the one-cent coin, the penny. The staple of change purses had been retired and would soon head the path of the $1 and $2 bills. While the reaction from Canadians was mixed, there was a general consensus that the loss, while timely and cost-effective, was still a sad end to a 105-year era.
The moment was also a sombre day for those striving to improve public health.
While the penny's only contribution to an individual's health is presumed to be good luck, there is another rarely known property of the lowly coin. It is a rather effective antimicrobial and can help to keep those fingertips clean.
The active component of pennies is copper, which has the ability to kill certain bacteria, fungi and viruses through contact. The mechanism is relatively simple: copper is a toxic heavy metal and slowly degrades when put into contact with anything that is wet. When the metal is released into an unsuspecting microbe, the consequences can be dire. The ions cause significant stress on the makeup of the cell and over time, cause it to either break apart or simply give up the will to live. It won't make a surface -- or your skin -- sterile, but it can definitely help to keep the burden of bacteria low.
The effects were first discovered by the agricultural industry back in the 1940s and were soon implemented to help prevent microbial spoiling of plants and fruits. The use of a particular mix of copper and sulphur, better known as copper sulphate, is a regular part of the winemaking process and may also help prevent lameness in livestock caused by a condition known as footrot. But it wasn't until the turn of the millennium when the true antimicrobial value of copper -- and the penny -- became apparent.
Ten years ago, there was a concerted effort to identify novel ways to prevent the spread of infections in the hospital environment. Regular cleaning and disinfection was the norm but a group of researchers were more interested in looking at alternate, passive means to kill these sometimes deadly pathogens. By taking surfaces made primarily of copper, they tested whether they could kill bacteria such as the number one foodborne illness, Campylobacter, the always troublesome methicillin resistant Staphylococcus aureus (MRSA), the sometimes deadly Clostridium difficile and even the new antibiotic resistance bacteria known as Carbapenem-Resistant Enterobacteriaceae, more easily called CRE.
The results were promising in almost all cases and soon there was a push towards the use of copper surfaces in hospitals to help prevent against the transmission of infectious disease. The copper industry even sought and gained the approval from the U.S. Environmental Protection Agency to officially call such surfaces antimicrobial. The influence of copper has become so popular that there is now interest in using copper-impregnated fabrics and textiles to help reduce the potential for infection during daily life.
But alas, while the microbicidal wonders of cooper continue to flourish, there is little that can be done for the penny. While the potential to help prevent infections is now a given, there is simply no way to convince the Mint to bring back the penny on the grounds of improved health. Besides, despite all the news promoting copper, there is one unfortunate drawback that may kill the penny's chances altogether.
In all of the studies where copper surfaces demonstrate an ability to kill germs, the surface was always clean and pristine. In fact, the only way that copper has any significant effect is when the surface is cleaned regularly. For something as ubiquitous as the common penny, this realization is all but a death knell to any chances of making a comeback. While hospitals and other institutions have cleaning and disinfection staff to keep their copper active, there is no such mechanism to help the coin -- its time is therefore certainly over.
Yet there is a chance to hold onto not just the memory but also the benefits of the forsaken denomination. Rather than store the coins in piggy banks and cardboard rollers, one can take them and sew them into the pockets of your pants, coats, and other clothing item. When there is a moment of concern -- and a lack of proper handwashing facilities and/or hand sanitizer -- rub those fingers on the penny and know that at least in the short term, the level of germs on your skin may be lessened. When you wash them in the laundry later on, you'll know that your penny will get that cleaning needed to keep it effective.
Just remember to sew it in face up to keep with the superstition of good luck. After all, when dealing with germs, you can never have too much of that.