Analysis of 500-ng/1 levels of bromate in drinking water by direct-injection suppressed ion chromatography coupled with a single, pneumatically delivered post-column reagent

In July 1997, the US Environmental Protection Agency (EPA) began sampling a nd analyzing drinking water matrices from US municipalities serving populat ions greater than 100 000 for low-level bromate (>0.20 mu g/l) in support o f the Information Collection Rule (ICR) using the selective anion concentra tion (SAC) method. In September 1997, EPA published Method 300.1 which lowe red the Method 300.0 bromate method detection limit (MDL) from 20.0 to 1.4 mu g/l This paper describes the research conducted at the EPA's Technical S upport Center laboratory investigating a single post-column reagent, o-dian isidine (ODA), which has been successfully coupled to EPA Method 300.1 to e xtend the MDL for bromate, Initial studies indicate that this method offers a MDL which approaches the EPA's SAC method with the added benefit of incr eased specificity, shortened analysis time and reduced sample preparation. The method provides excellent ruggedness and acceptable precision and accur acy with a bromate MDL in reagent water of 0.1 mu g/l, and a method reporti ng limit of 0.50 mu g/l. (C) 1999 Elsevier Science B.V. All rights reserved .