Capsules and air

Hello, if I put a coin in a capsule and close the capsule, can the air that is "permanently" sealed inside the capsule do anything bad to the coin? I ask because probably none of us live in a completely sterile environment, and most of us don't have an ultra-clean lab to put coins in a capsule (obviously if we use them :-) ). For example, I put coins in a capsule in my room where I eat, work, etc. I suppose by the very nature of capsules as an idea, the matter of capsules and the air inside had to be conceived of somehow. What is the truth?

I think, when you close the capsule properly, and do not open it again, the amount of air trapped inside
 is to small to do any harm to a coin.
Unless you did it in a very polluted envoirement, but that would also have affected the coin's owner…
If you want to be sure the capsules are 100% air-thight, you can use super-glue to glue the lid on the actual

 capsule.
But for me, personal, it seems to me that you are a little bit over-reacting, better relax and enjoy your

 coin-collection.
It is, ofcourse, a good thing to handle your coins with maximum care, but nothing last forever…unfortunately

yvon

I think, when you close the capsule properly, and do not open it again, the amount of air trapped inside
 is to small to do any harm to a coin.
Unless you did it in a very polluted envoirement, but that would also have affected the coin's owner…
If you want to be sure the capsules are 100% air-thight, you can use super-glue to glue the lid on the actual

 capsule.
But for me, personal, it seems to me that you are a little bit over-reacting, better relax and enjoy your

 coin-collection.
It is, ofcourse, a good thing to handle your coins with maximum care, but nothing last forever…unfortunately

Thanks!

If you removed all the air in the airtite before closing it, it would slowly come back in anyhow.  

The polymer is still permeable to nitrogen, oxygen and water vapor.

.900 silver 42 years in sealed plastic:

.900 silver 42 years in unsealed capsule (that's been opened several times for pictures):

Neither has any signs of developing a patina.

Nicely reinforcing the notion of “put it in a holder and fugeddaboudit.”