A few drops of iodine--not enough to stain--kills pritmuch EVERYthing without attacking fabric like bleach does.
I dunno where some get their FL data, but mine is 15yo, doesn't stink and never did. I don't use any heroic measures to keep it so, just towel the boot when done. Wash temp ~100F, just enough to liquefy sebum (skin oil/wax).