[Calvin Locke]

Eh, just add a drop or two of [tincture of] iodine into the your glass/bottle of water.

My father said one of his sisters had to do that for a brief time around WWII, and I think she just turned 90 a couple of weeks ago.

Disclaimer: Check with your MD...

[Sacajaweau]

I’m not too far from a nuclear plant. They distribute iodine on a regular basis.