Article on The Internet Mini Encyclopædia
Spray the crap out of everything with Lysol (tm) or some UK equivalent (mould and mildew killer / deodorant)
Hold the opening of a brown paper grocer's bag (the brown bags we used to blow up and then pop loudly) into a small circle by crumpling it up, then blow up the bag like a balloon.
In this case though, resist the temptation and don't pop it, just crunch the opening more or less closed and pitch the bag into the car along with about 3 dozen more of them done the same way. This will dry things out semi-miraculously.
After enough time, the bags may become damp and mildewy. Just pitch them in the bin and install a new set.
I think that if you blow the bags up outdoors, using the colder air, the air inside of them will be even drier, even with the added moisture from your lungs.
The brown paper absorbs incredible amounts of moisture. Corrugated cardboard (pasteboard) boxes disassembled to lie flat are even better. The air inside a box storage facility gets so dry they have to use humidifiers and special breathing gear.
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