Water testing for bromate has become important because even very low levels of bromate,found in drinking water,are potentially carcinogenic when ingested. It is because of the health hazards of bromate that it is now mandatory to carry out bromate testing in water.
Not many people know that bromate is actually a by-product formed when water is disinfected. When environmental pollutants make their way into water then it becomes necessary to disinfect the water. Ozone gas is used for disinfection because it is considered an antimicrobial agent that can successfully remove bacteria and other microorganisms in drinking water. However, if bromide or bromine is present in water, ozone gas reacts with them to form bromate and water testing can determine the level of bromate.
Water testing for bromate is not just confined to tap or potable water but packaged drinking water is equally susceptible to bromate contamination. To reduce heavy metal and pesticide residues to Bureau of Indian Standards (BIS) standards for drinking water, a number of packaged drinking water companies follow the same method of disinfection with ozone. After studies found the presence of bromate in a number of packaged water samples, BIS has made it mandatory to test packaged drinking water for presence of bromate.
BIS has also fixed the maximum permissible limit of bromate in water at 0.01microgram per litre. Chemical testing laboratories carry out water testing for all kinds of contaminants so water is safe to drink, whether tap/ potable water or packaged drinking water. Companies that produce packaged drinking water must get their packaged water samples tested for the absence of bromate at regular intervals. This will help them to comply with the requirements of licensing from BIS.
Small amounts of bromate ions can also be formed by a process of photo activation. When water is exposed to sunlight it causes liquid or gaseous bromine to react with oxygen and this also leads to the formation of bromate in water.Chemical testing laboratories can determine the level of bromate concentration in water and help to ensure that it is within recommended levels so it does not affect consumer health. Since bromate testing requires sophisticated instrumentation and complex testing methods, only recognised testing laboratories, that have the equipment and the know-how can successfully test the levels of bromate concentration in water.
It is a challenge for testing labs to determine bromate content or its absence in water as the methods for testing water for bromate need careful handling and accurate analysis of the result. BIS 8th Amendment for packaged drinking water not only lays down the standards for bromate content in water but prescribes the use of ion exchange liquid chromatographic method as the best method for testing for bromate. Though there are a number of other methods for analysing bromate ions in water, but since recommended levels of bromate are very low, only the services of chemical testing laboratories that use ion chromatographic method must be used for bromate testing in water.