A very long time ago, recorded in a book now known as the Smith Papyrus around 2600 to 2200 B.C, is reported to be the use of copper to sterilize chest wounds and drinking water. In another papyrus, the Ebers Papyrus, written around 1500 B.C., it’s reported that copper compounds were recommended for things like headaches, burn wounds, and ‘trembling of the limbs’.
Over the centuries, copper has continually been found to be extremely beneficial in the medical field, and in 1832 copper workers were found to be immune to cholera. Today this is known as contact killing, and while copper bracelets and copper-based medicines were once commonly ridiculed as hoaxes and ‘voodoo witch doctoring’, it “has recently been registered at the U.S. Environmental Protection Agency as the first solid antimicrobial surface material.”, according to the American Society of Microbiology. Don’t let that quote confuse you. Silver continues to be our favorite anti-just-about-everything but, as a surface material, copper plays an equal part.
While copper has clearly been used for everything from tinctures to drinking utensils, and it is actually one of the elements in our body, oftentimes copper alloys, just like the copper remedies and treatments themselves, are forgotten or dismissed. Say hello to copper’s alloy: brass.
Brass has some unique properties.
Like silver and copper, brass is antimicrobial. According to Professor Bill Keevil, head of the microbiology group at Southampton University, “Until relatively recently brass was a relatively commonly used surface. On stainless steel surfaces, these bacteria can survive for weeks, but on copper surfaces, they die within minutes. Part of the process DNA from bacteria is also destroyed just as rapidly on the copper, so you cannot get gene transfer on the surface.”
Metals that kill germs on the surface? Yes. We’ve all known for quite a while that silver is priceless in the medicine chest. So too is copper and its alloys. Steel and stainless steel can’t boast these properties. It’s called The Oligodynamic Effect, and it’s defined as a toxic effect of metal ions on living cells, algae, molds, spores, fungi, viruses, prokaryotic and eukaryotic microorganisms, even in relatively low concentrations. In laymen’s terms, copper, brass, and bronzes are germ assassins. In a study by the National College of Kathmandu in Nepal, silver, brass, and copper were tested against water that had small doses of E. coli and Salmonella in it. Within 12 hours both bacteria had been eliminated completely.
Enter the copper/brass doorknob. These types of doorknobs have been around for a very long time, but it’s only been comparatively recent since the investigative report that the metals do indeed have a contact kill. This makes copper utensils like bowls and cups, and brass doorknobs, more enticing in an ever-increasing antibiotic-resistant world. And in a post-apocalyptic environment.
But to retain those properties, you must keep your brass clean.
If the brass or copper has a lacquer finish though, its antimicrobial properties are nil, and unfortunately, we also know that copper and its alloys experience corrosion, primarily from salt. Even more recently has been the discovery that human sweat is usually the major culprit.
According to Dr. John Bond OBE, from the University of Leicester’s Department of Chemistry, the sweat from people can cause enough corrosion on these metals to adversely affect the ability to kill various microorganisms. The corrosion forms an oxide layer, which in turn is what inhibits the ability to kill bacteria, and this can only be fixed by proper cleaning of the metal.
You could use a commercial cleaner to clean copper and brass, but in reality, all you need are three base ingredients and some elbow grease. Vinegar, flour, and salt. Or lemon juice and baking soda. Or… ketchup..? All of these work because of the acid-base in the vinegar, lemon (or lime juice if you choose), and tomatoes found in ketchup. The acid strips the oxidation from the metal and the flour/baking soda serves as a soft scrub base. Polish your metal with your choice of homemade cleansers and a soft cloth, then rinse with warm water and dry, then buff it to a shine.
Before you do any cleaning of the metal though, check to see if it’s solid copper/brass, or plated. If it’s plated, you could inadvertently end up rubbing the thin plating off. It’s easy to check: Get a strong magnet. If it sticks to the item, it’s plated. If it doesn’t it’s solid.
Copper is being used more frequently for similar reasons.
Brass is used commonly in locks, ammunition casings, and doorknobs (usually because low friction is required), but it should not be used for cooking or eating utensils. This is because brass is a copper alloy; meaning it contains either nickel or zinc along with copper. We don’t want to ingest nickel or zinc in this way. But decorations, doorknobs, beautiful dresser drawer, and kitchen cabinet handles, faucet fixtures, jewelry clasps, light switch plates, even picture frames; these would all be beautiful and helpful in keeping bacteria at bay if we replaced them with brass ones instead.
Copper is being reintroduced as pots, pans, and skillets again, and they’re perfectly safe as long as they have an inner liner made of something like stainless steel. Imagine a pot that automatically kills the bacteria and germs on the outside long after you’ve washed it, jewelry, and even mugs, that resist bacteria and really can keep you from getting sick. And businesses are catching on as well.
In Chile, they have installed copper metal roofs in hospitals, added copper to clothing threads, and in January 2017 copper railings were placed in the entrance ramp of a popular roller coast and on the handlebars of the cars of that ride. In France “Bed rails, trolleys, taps, handrails, door handles, soap dispensers, light switches and push plates made of copper, or copper alloys like brass and bronze, were fitted throughout the hospital’s intensive care and pediatric units.”
As I finish this article I look around into the kitchen. I love my stainless steel knives, stainless steel kitchen sink, and some sort of BPA free hard plastic cutting boards… Plastic handles on the microwave, the stove, some weird plastic-type handle with a fake metal on my cabinets…Even the shelves in, and on, my fridge are plastic and glass… And I wonder how many germs and bacteria are on all that stuff just from the air itself. Then I look at the iron skillets and old brass doorknob on the kitchen door; a doorknob that smells of metal – you know the smell – the one you go straight to the sink to wash off? I think it’s amazing how far we’ve gone backward while moving forward.
“We live in this new world of stainless steel and plastic, but perhaps we should go back to using brass more instead.” Professor Bill Keevil, Head of Microbiology, Southampton University.
What do you think?
Do you own brass items? If so, do you clean them often? Please share your thoughts in the comments.
About Sandra
Sandra is a published artist, photographer, fellow prepper, and animal advocate.
Well… Nice to know that the brass spurs I wear daily (they were my grandfather’s) are free of “bugs”!
Definitely useful information. Don’t forget bronze. Wood is also antibacterial. Both beat out plastic, which has no antimicrobial value at all.
Swords, knives and axes were made of bronze till iron became more available. Iron was more durable if looked after but lacked copper’s advantages in ductility and corrosion resistance.
Bronze persisted in things like scalpels but was a valuable alloy in and of itself. We have perfect bronze artifacts from thousands of years ago with just a light patina of oxidation, but iron tends not to last.
Wood is good for cutting boards and splints, and many artisans still sell bronze weapons and other tools including swords.
You missed a wonderful example of the use of another copper alloy: tumbago, a mix of copper with gold or gold and silver. It was how Native peoples of the Americas typically processed gold prior to European contact. Gold reduces tarnishing and oxidation of copper, extending both the beauty and the anti-infectious quality of the copper. Ancient warriors with large flat gorgets around their necks probably had these available to reduce infections from injuries.
It’s nice that you talked about how brass is antimicrobial like silver and copper. I was checking out a book last night and it listed the various uses of brass nowadays. It seems it is easy to get brass metal supply nowadays due to the huge demand for the material.
I work in a hospital, and I have a solid brass pen I use in patient’s rooms. It’s the one item I use when my hands may be dirty, and the last thing I think of to clean. I wear it on a lanyard (it has a brass ring on top and is quick to disconnect) and that reminds me to clean it when I clean off my hospital phone.