Mold and Old Currency

[Mike1961]

I had some old currency in a metal gun cabinet stored in my Mom’s garage and recently her roof started leaking. Well, some of the stuff in the cabinet did get damaged from moisture. The old currency is not bad but it does have a strong moldy smell and I suspect that mold has started growing on it, even though none is visible. I’m afraid that mold could damage the bills and was wondering if anyone knows anything I could do about it. I actually considered ironing the bills in hope that it would kill the mold. Any thoughts or suggestions?

[007tallguy]

maybe spend some of your money so it doesn't get so moldy!

ok, seriously... i'm not sure about the "after the fact" mold, but maybe a couple of those silica gel packets that are packed in with electronics to keep moisture from being a problem.
i wouldn't recommend using any kind of cleaners on those bills, other then just wiping them down with a dry cloth to wipe away any mold. you may not actually see any mold on them, but if you can smell it, it's likely microscopic and present on the bills. clean them individually and then pack them up with the gel packs.

Pete

edit: you can probably pick up several of those silca packets for free from any camera or electronics shop.

[Mike1961]

1935 Silver certificate, some old $2 dollars bills, so don't want to spend these. The smell is not my biggest concern, I'm worried that the mold is still growing. The silica packs are a good idea for anything else I put in storage and they might help with any remaining moisture. Thanks

[007tallguy]

Originally Posted by Mike1961

1935 Silver certificate, some old $2 dollars bills, so don't want to spend these. The smell is not my biggest concern, I'm worried that the mold is still growing. The silica packs are a good idea for anything else I put in storage and they might help with any remaining moisture. Thanks

i was just kiddin' about spending it.
have you tried googling "mold"? the heat from the iron may very well kill it and the gel packets should keep it at bay afterwards.

[Jax]

Not sure if it will help with Mold, but will suck the moisture out

Seal them in a bag or box with uncooked white rice. When I got my cell phone and watch wet, this worked perfect.

[Mike1961]

Originally Posted by 007tallguy

i was just kiddin' about spending it.
have you tried googling "mold"? the heat from the iron may very well kill it and the gel packets should keep it at bay afterwards.

I know that 007.

I was thinking that the iron might kill the mold but I was also concerned it could damage the currency. The gel packs, or uncooked rice as Jax suggested, would keep the moisture down which should reduce the risk of mold. Still, I am concerned about introducing heat to the bills.

[WTR25]

Before putting them somewhere with silica packs, try microwaving each bill individually for about 10-20 seconds to get any moisture out. Its worked for me in the past with dropping my wallet in water.

[Mike1961]

Originally Posted by WTR25

Before putting them somewhere with silica packs, try microwaving each bill individually for about 10-20 seconds to get any moisture out. Its worked for me in the past with dropping my wallet in water.

That's a thought. Wonder if it would kill any mold that is growing on them but not yet visible?

[007tallguy]

Originally Posted by Mike1961

That's a thought. Wonder if it would kill any mold that is growing on them but not yet visible?

i read a little bit of stuff on it and the first step is to give the bills a wipe-down with a dry cloth first. if you use a damp cloth, you can actually force some of the mold/spores into the bills. that can in turn, stain them and it increases the chances of the mold growing again.
and one of the most common things i see mentioned is to place the item (in this case, your bills) in direct sunlight for about an hour and that will supposedly kill the mold.
to prevent it from re-growing, store them in a cool, dry place. this is where the silica packs will come in handy.
that's just a very brief rundown on some of what i found through google, but there's LOTS of info out there. personally, i would avoid using any kind of cleaners since those can destroy your money, fade it or stain it and you don't want that to happen.
i don't see why the iron wouldn't work after you wipe them down, just don't use a steam setting. mold thrives on moisture.
hope this helps,

Pete

[Mike1961]

I won't use any cleaners. Have considered freezing them for a short time. I’ve heard that museums sometimes do that with old books to killing parasites that might damage them but not certain if that is true.

[007tallguy]

Originally Posted by Mike1961

I won't use any cleaners. Have considered freezing them for a short time. I’ve heard that museums sometimes do that with old books to killing parasites that might damage them but not certain if that is true.

actually yes. i remember reading something about dry ice being one thing that helps kill off the mold.
this write-up is referring to mold removal from a house, but it explains how the process works:

"Dry ice blasting accomplishes mold remediation faster and more completely than mechanical abrasion. Dry ice blasting does not require toxic chemicals and does not create a toxic dust hazard from remediation operations."

and a little bit more about what the dry ice does:

"Dry ice blasting for mold remediation uses four physical properties of air-propelled dry ice pellets: velocity, abrasion, thermal shock, and evaporation. Dry ice is solid (frozen) carbon dioxide. For blasting uses, dry ice is manufactured in pellets of various sizes appropriate to the substrate to be cleaned. The pellets are hurled from a blasting gun by air pressure, which provides the velocity. When the pellets strike the surface to be cleaned, three things happen. First the velocity of the pellet strikes the substance to be removed. Because dry ice is at a temperature of -109 degrees F., the thermal shock helps loosen and lift the substance to be removed. Finally, the dry ice pellet flashes into carbon dioxide gas, providing more lift to the substance to be removed. The carbon dioxide gas is harmless, leaving no cleaning material such as sand or solvents to be cleaned up after the cleanup."

again, that for ridding it from a house, so your bills would be a much smaller scale cleaning process, lol.

[Mike1961]

Originally Posted by 007tallguy

actually yes. i remember reading something about dry ice being one thing that helps kill off the mold.
this write-up is referring to mold removal from a house, but it explains how the process works:

"Dry ice blasting accomplishes mold remediation faster and more completely than mechanical abrasion. Dry ice blasting does not require toxic chemicals and does not create a toxic dust hazard from remediation operations."

and a little bit more about what the dry ice does:

"Dry ice blasting for mold remediation uses four physical properties of air-propelled dry ice pellets: velocity, abrasion, thermal shock, and evaporation. Dry ice is solid (frozen) carbon dioxide. For blasting uses, dry ice is manufactured in pellets of various sizes appropriate to the substrate to be cleaned. The pellets are hurled from a blasting gun by air pressure, which provides the velocity. When the pellets strike the surface to be cleaned, three things happen. First the velocity of the pellet strikes the substance to be removed. Because dry ice is at a temperature of -109 degrees F., the thermal shock helps loosen and lift the substance to be removed. Finally, the dry ice pellet flashes into carbon dioxide gas, providing more lift to the substance to be removed. The carbon dioxide gas is harmless, leaving no cleaning material such as sand or solvents to be cleaned up after the cleanup."

again, that for ridding it from a house, so your bills would be a much smaller scale cleaning process, lol.

Thanks. I wonder if simply freezing them would kill the mold, though it seems possible that in the freezin and thawing process they might pick up more moisture, which would make dry ice perfect for this.