Silver has been suggested by some for water treatment.Its use is currently out of favor due to the EPA’s establishment of a 50 ppb MCL (Maximum Contaminate Level) limit on silver in drinking water.This limit is set to avoid argyrosis, a cosmetic blue/gray staining of the skin, eyes,
and mucous membranes.

As the disease requires a net accumulation of 1 g of silver in the body, one expert calculated that you could drink water treated at 50 ppb for 27 years before accumulating 1 g. Silver has only be proven to be effective against bacteria and protozoan cysts, though it is quite likely also effective
against viruses.

Silver can be used in the form of a silver salt,commonly silver nitrate, a colloidal suspension,or a bed of metallic silver. Electrolysis can also be used to add metallic silver to a solution.

TIPS: Silver deposited on carbon block filters can kill pathogens without adding as much silver to the water.