K-D
He should keep the bleach for other hygenic uses. If there is a true disaster and you are either in large groups and or without ultilities it is very easy for a lot of people to get gastro-intestinal illnesses, the flu etc. A light bleach solution is a great way for people to rinse their hands and even eating utensils. Remember the "dunk bag" in the Boy Scouts or summer camp?

Also now that there are chlorine-dioxide productson the market; iodine is obsolete.
Iodine is not effective on Cryptosporidia (sp?) but products like MP1, Potabale aqua chlorine-dioxide, and Aqua Mira are. They leave no taste, color or aroma.
The instuctions require a longer waiting period but that is for the most extreme cases and the manufacturer's lawyers.