AWWA WQTC64117

Currently, no standards exist for the holding time and temperature of Legionella water samples. The purpose of this study is to determine the optimal holding time and temperature for Legionella samples collected from water. Deionized water samples were spiked with known quantities of Legionella pneumophila to test the recovery rate at different times and temperatures using the filtration method. The spiked water samples were analyzed at 0 hours, 24 hours, 48 hours, 72 hours, and 120 hours. Results indicate Legionella colonies decrease significantly if samples are analyzed more than 24 hours after collection. One set of samples was held at room temperature and another set was preserved at 4º C in a refrigerator. Lower amounts of Legionella were observed in samples held at 4º C than in room temperature samples. Includes 8 references, table, figure.