A NEW MEMBRANE FILTRATION MEDIUM FOR SIMULTANEOUS DETECTION AND ENUMERATION OF ESCHERICHIA-COLI AND TOTAL COLIFORMS

Recovery of total coliforms and Escherichia coli on a new membrane fil tration (MF) medium was evaluated with 25 water samples from seven sta tes. Testing of the new medium, m-ColiBlue24 broth, was conducted acco rding to a U.S. Environmental Protection Agency protocol. For comparis on, this same protocol was used to measure recovery of total coliforms and E. coli with two standard MF media, m-Endo broth and mTEC broth. E. coli recovery on the new medium was also compared to recovery on nu trient agar supplemented with 4-methylumbelliferyl- beta-D-glucuronide , Comparison of specificity, sensitivity, false positive error, undete cted target error, and overall agreement indicated E. coli recovery on m-ColiBlue24 was superior to recovery on mTEC for all five parameters . Recovery of total coliforms on the new medium was comparable to reco very on m-Endo.