Bromates

Bromates are salts or esters of bromic acid containing the bromate ion, BrO3−. The bromate ion has bromine in the +5 oxidation state and is a relatively strong oxidizing agent. Common bromates include potassium bromate (KBrO3), sodium bromate (NaBrO3), and calcium bromate (Ca(BrO3)2). In water and many chemical systems, bromates are formed when bromide-containing solutions are oxidized, such as during ozone or certain chlorine-based disinfection processes under alkaline conditions. They are regarded as disinfection byproducts and are typically present only in trace amounts unless conditions favor their formation.

In industry, bromates are used as oxidizing agents in various syntheses. Potassium bromate has historically been used as a flour improver, but its use is restricted or banned in many countries due to safety concerns. Bromates also appear in laboratory settings as reagents and in redox titrations. As solids, they are generally sparingly soluble in water, and in solution they dissociate to BrO3− ions.

Safety and regulation focus on their strong oxidizing properties and potential health effects. Bromate ion is considered a potential carcinogen by some health agencies, and regulatory limits are set for drinking water and, in some regions, for certain foods and manufacturing contexts. Detection and removal methods in water treatment include activated carbon, reverse osmosis, and ion-exchange processes to limit bromate levels in finished water.