16 May 2013, 01.53 AM
silver facts & history
Usually when we talk about the health effects of silver, we’re talking about its antibacterial properties, not its potential toxicity, but like anything else, eat too much silver and it will make you sick. There’s even a name for the disease: argyria. But, most sicknesses don’t have quite such entertaining symptoms:
Mime Artist by Michael Drummond
Ok, that’s a mime, not a disease, but thanks to Science Codex, we discover How silver turns people blue:
To find out, the researchers mixed a series chemical treatments that could simulate what might happen to silver inside the body. One treatment simulated the acidic environment in the gastrointestinal tract; one mimicked the protein content of the bloodstream; and a collagen gel replicated the base membranes of the skin.
They found that nanosilver corrodes in stomach acid in much the same way it does in other acidic environments. Corrosion strips silver atoms of electrons, forming positively charged silver salt ions. Those ions can easily be taken into the bloodstream through channels that absorb other types of salt. That’s a crucial step, Hurt says. Silver metal particles themselves aren’t terribly likely to make it from the GI tract to the blood, but when some of them are transformed into a salt, they’re ushered right through.
From there, Hurt and his team showed that silver ions bind easily with sulfur present in blood proteins, which would give them a free ride through the bloodstream. Some of those ions would eventually end up in the skin, where they’d be exposed to light.
To re-create this end stage, the researchers shined ultraviolet light on collagen gel containing silver ions. The light caused electrons from the surrounding materials to jump onto the unstable ions, returning them to their original state — silver metal. This final reaction is ultimately what turns patients’ skin blue. The photoreaction is similar to the way silver is used in black and white photography. When exposed to light, silver salts on a photographic film reduce to silver metal and darken, creating an image.
Who knew you could turn people into photographic film? Spend a day on the beach in the sunshine, take a bath in acetic acid, and shower yourself off with photo fixer and you could become a human photograph. Of course, the developing fluids might end up being more toxic than the silver itself, but nobody ever said you didn’t have to make sacrifices for art.
Of course, you’d have to ingest an abnormally large amount of silver to develop this condition — the disease shows up mainly in people who drink antimicrobial health tonics containing silver nanoparticles and in people who have had alternative medical treatments involving silver. I guess this means you can’t have the antibacterial properties of silver without the photosensitive ones.
Since turning blue appears to be the only observable symptom of the disease, we can’t help wondering how long it will be before some troubled teenager accidentally starts the next craze in body modification. You could become a Na’vi from Avatar, or take the Zombie Walk to a whole new level.
The only downside is, like tattoos, argyria is permanent. And, unlike tattoos, there is no known cure.