253 Title: Bromide and Bromate Concentrations in Bottle Waters and Selected Tap Waters in Houston, Texas Area

Thursday, November 5, 2009: 1:40 PM
Kohlberg (Camino Real Hotel)
Wasiu A. Lawal, Mr , Department of Chemistry, University of Houston-Clear Lake, Houston, TX
Jayesh Gandhi, Dr , Metrohm USA, Riverview, FL
Chunlong Zhang , Department of Chemistry, University of Houston-Clear Lake, Houston, TX
Bromide is ubiquitously found in drinking water. It is introduced into source water primarily by contact with bromide-containing soils or seawater having high bromide content. Bromide is converted into carcinogenic bromate during ozonation processes employed in some drinking water and wastewater treatment plants.  Therefore, monitoring of bromate in drinking water and its precursor bromide in source water is required. The purpose of this study was to survey bromide and bromate concentrations in randomly selected bottle waters of various brands and several tap water samples in the coastal Houston area, using a direct-injection ion chromatography (IC) and suppressed conductivity system (Metrohm USA). The method employs a simple isocratic IC with loop injection with detection limit of 0.009 µg/L for bromate and 0.028 µg/L for bromide. Allowing the detection of both species at the µg/L level in drinking water, this method does not require specialized instrumentation such as two-dimensional ion chromatography, expensive sample preparation or post-column reactions. Our results show that tap water near the coastal zone has higher concentration for bromide due to salt water intrusion; whereas bottle water samples that underwent ozonation contained high levels of bromate. This presentation will demonstrate detection rate and average concentration of 20 ozonated bottle water samples. Also, reference from previous work done at the University of Houston – Clearlake will be provided.