Alternative drinking-water disinfectants: bromine, iodine and silver

Overview

Disinfection of water has greatly contributed to reducing risks to public health from microbiologicallycontaminated drinking-water.

Elemental bromine (Br2), bromine monochloride (BrCl), hypobromous acid (HOBr- ) and bromodimethylhydantoin are used in swimming pools and marketed as a replacement for chlorine, with one advantage being that there are no asthma-related problems for individuals in contact with the disinfected water (e.g. swimmers and/or lifeguards).

In terms of the disinfection of drinking-water, iodine is commonly used in the form of tablets or solutions during emergencies and by travellers (Ongerth et al., 1989; Backer & Hollowell, 2000).

the increased use of nanosilver in a range of (as yet largely) experimental drinking-water treatment systems, its use in conjunction with ceramic filters, and its perceived potential to be a water disinfectant that does not result in disinfection by-products in the treated water, have raised the profile of this chemical. 

The emphasis of this literature review is to evaluate the available evidence on the biocidal efficacy and toxicity of bromine (Br2, and other forms),  iodine and silver as a water disinfectants.