[mixologic]

Have you checked for Radon?

[ajross]

Radon is a noble gas and chemically inert. It's radioactive, which is why it's a toxicity worry. But there was enough radiation in that basement to mechanically damage plastic in three years, OP would be long since dead.

[lima]

Radon and its progenitors won't produce nearly enough radiation to damage plastics like that at naturally occurring levels.