The US EPA Office of Ground Water and Drinking Water has approved the use of electrolytically generated hydroxide eluents and associated hydroxide-selective columns for methods 317.0 and 326.0
Both methods use addition of a post-column reagent and absorbance detection to determine trace levels of bromate.
Now reagent-free IC systems with eluent generation (RFIC-EG systems) can be used for drinking water compliance monitoring of bromate using these two methods.
Bromate, formed from the ozonation of drinking waters containing bromide, is a regulated disinfection by-product with well documented toxicological effects.
The US EPA has established a regulatory maximum contaminant level (MCL) of 10ug/L bromate in drinking waters.
Bromate can be difficult to determine in the high-ionic-strength matrices often found in drinking waters.
Post-column addition of o-dianisidine (method 317.0) allows detection of bromate using visible light.
Addition of acidified potassium iodide (method 326.0) allows UV detection of bromate ions.
Absorbance detection is specific to the chromophore produced by the reaction with bromate, allowing detection of trace amounts of the anion even in the presence of co-eluting species.
Dionex Application Note 168 describes the use of an RFIC-EG system for bromate determination by EPA Method 317.0, and is available on the Dionex website.
Dionex Application Note 171 describes the use of an RFIC-EG system for bromate determination by EPA Method 326.0, and is also available on the Dionex website.
