The specific aims of this project are to test the antimicrobial activity of certain organic N-halamines and to involve undergraduate students in research. The compounds to be tested are 1,3-dichloro-4,4,5,5-tetramethyl-2-imidazolidinone (agent A), 1,3-dibromo-4,4,5,5-tetramethyl-2-imidazolidinone (agent AB), and 1-bromo-3-chloro-4,4,5,5-tetramethyl-2-imidazolidinone (agent ABC). This series of compounds will be utilized at 25 degrees and 37 degrees C and pH 4.5, 7.0, and 9.5 to cover conditions anticipated in natural, buffered, and softener treated waters. The compounds will be tested at 1, 2.5, 5 and 10 mg/l Cl+ or the molar equivalent of Br+ to include concentrations frequently used in disinfection testing. Based on preliminary screening, the compounds should be effective disinfectants. Once the efficacy is determined, the long-term objectives are to test the carcinogenicity and toxicity of the compounds. Legionella pneumophila was chosen as the test organism for several reasons. This organism, present in water and soil, is the causative agent for Legionnaire's disease. It is found in cooling water for air conditioning systems and circulating hot water systems such as those found in hospitals. Legionella creates a health risk for compromised patients through nosocomial pneumonias.
