40 CFR 180.519: Bromide ion and residual bromine; tolerances for residues.

(a) General. The food additives, bromide ion and residual bromine, may be present in water, potable in accordance with the following conditions:

(1) The food additives are present as a result of treating water aboard ships with a polybrominated ion-exchange resin (as a source of bromine) under the supervision of trained personnel.

(2) Residual bromine levels are controlled to not exceed 1.0 part per million (ppm) in the final treated water. Control is effected using calibrated recirculating or proportioning bromine feeder equipment and periodic checks of residual bromine using a bromine test kit. To assure safe use of the additives, the label and labeling of the disinfectant formulation containing the food additives shall conform to the label and labeling registered by the U.S. Environmental Protection Agency.

(3) No tolerance is established for bromide ion levels.

(b) Section 18 emergency exemptions. [Reserved]

(c) Tolerances with regional registrations. [Reserved]

(d) Indirect or inadvertent residues. [Reserved]