Bromate

Ivanhoe Reservoir looking northeast from west side 2015-10-11

Bromide ion

Hypobromite ion Space Fill

Bromite-ion-from-xtal-1989-Mercury-3D-sf

Bromate-3D-vdW

Bromate is an anion with the chemical formula BrO3−. It is formed when bromine is at a high oxidation state (+5). Bromates are powerful oxidizing agents and are found in many chemical reactions and industrial processes. The most common form of bromate in industrial and environmental contexts is potassium bromate, which is used in both the food and water treatment industries, among others.

Formation and Occurrence

Bromates are typically formed through the oxidation of bromide ions (Br−) in aqueous solutions, especially during water disinfection processes that use ozone (O3) or chlorine dioxide (ClO2) as oxidants. This formation can occur naturally in water bodies receiving high levels of ozone or artificially in water treatment facilities. The presence of bromate in drinking water is a significant concern due to its potential health risks, leading to strict regulation of its levels in many jurisdictions.

Uses

In Food Industry

Historically, potassium bromate has been used as a dough conditioner in the baking industry. It strengthens the dough and allows for higher rise and uniform texture in baked goods. However, due to health concerns, its use has been banned or restricted in many countries.

In Water Treatment

Bromates are used in the water treatment industry as part of the ozonation process. While effective in disinfecting water, careful control is necessary to minimize the formation of bromate byproducts.

Health Effects

Bromate is considered a potential carcinogen by several health and environmental agencies. Exposure to high levels of bromate can lead to adverse health effects, including an increased risk of cancer. The International Agency for Research on Cancer (IARC) has classified potassium bromate as a possible human carcinogen (Group 2B). As a result, there are guidelines and regulations to limit bromate concentrations in drinking water and food products to protect public health.

Regulation

Due to its health risks, the presence of bromate in food and water is regulated by various international and national agencies. The World Health Organization (WHO), the U.S. Environmental Protection Agency (EPA), and the European Union have set maximum allowable concentrations of bromate in drinking water. These regulations aim to minimize exposure to bromate and mitigate its potential health impacts.

Environmental Impact

Bromate can also pose risks to the environment. Its strong oxidizing properties can affect aquatic ecosystems, potentially harming aquatic organisms. The release of bromate into the environment, primarily through industrial effluents and water treatment byproducts, necessitates careful monitoring and management to prevent ecological damage.