Comprehensive review of bromate ion control in water intended for human consumption

The formation of bromate ions in drinking water poses a major public health concern due to their proven carcinogenicity. It is primarily linked to oxidation processes, particularly ozonation, in the presence of bromide ions and naturally occurring organic matter. Compliance with the 10 µg/L limit recommended by the World Health Organization (WHO) thus represents a significant challenge for water treatment systems. The formation of bromate depends heavily on the water’s physicochemical characteristics, notably bromide concentration and pH, while ozone dosage and temperature play a secondary role. This review offers a structured analysis linking bromide sources, formation mechanisms, health risks, and control strategies. The technologies studied include activated carbon adsorption, biofiltration, ion exchange resins, electrochemical processes, and membrane technologies. Their performance varies significantly depending on the water matrix and operating conditions, with notable discrepancies between results obtained at the laboratory scale and those observed at the industrial scale. The results show that effective bromate control relies on an integrated approach combining the prevention of its formation with its removal downstream. They also emphasize that bromate reduction must not lead to an increase in other brominated byproducts, which may be more toxic, requiring comprehensive process optimization based on both technological and health criteria.