Does anyone know the efficacy of chlorine dioxide tablets once they are removed from the foil wrapper?

I have some Katadyn Micropur MP1 tablets that I have removed from the foil wrappers and placed into a metal capsule that has an o-ring and I carry it around my neck. The capsule will hold 8 tablets. The o-ring is pretty soft and weak. I'm not so sure that they will stay airtight, but we'll see.

Have any of you tested something like this? If not, I'll wear them around my neck and then try to figure out some kind of test at Christmas time. I'm wearing the necklace now, and I don't plan on taking it off even in showers. Not sure how I could set up an experiment in my house though. I'm not exactly set up for biological experiments, lol. Any suggestions for creating a test environment would be welcome. Doesn't a Miox filter come with test strips? Maybe that would work?

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