The aqueous solution of hydriodic acid and elemental iodine, including one or both of the surfactants (a) polyoxypropylene-polyoxyethylene glycol nomionic block polymers (minimum average molecular weight 1,900) and (b) α-(p- nonylphenyl)-omega- hydroxypoly (oxyethylene) having a maximum average molecular weight of 748 and in which the nonyl group is a propylene trimer isomer, is exempted from the requirement of a tolerance for residues in egg, and poultry, fat; poultry, meat; poultry, meat byproducts when used as a sanitizer in poultry drinking water.