This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Edberg, S C Articles by Smith, D B Search for Related Content PubMed PubMed Citation Articles by Edberg, S C Articles by Smith, D B Agricola Articles by Edberg, S C Articles by Smith, D B

 Previous Article  |  Next Article 

Appl Environ Microbiol. 1989 April; 55(4): 1003-1008

National field evaluation of a defined substrate method for the simultaneous detection of total coliforms and Escherichia coli from drinking water: comparison with presence-absence techniques.

Department of Laboratory Medicine, Yale University School of Medicine, New Haven, Connecticut 06510.

ABSTRACT

A defined substrate method was applied to drinking water to simultaneously enumerate total coliforms and total Escherichia coli directly from samples. After incubation at 35 degrees C for 24 h, the development of yellow in an initially colorless solution was specific for total coliforms; fluorescence at 366 nm in the same tube(s) or vessel demonstrated the presence of E. coli. No confirmatory or completed steps were necessary. Known as autoanalysis colilert (AC), this method was constituted as a presence-absence test and compared with the methods described in Standard Methods (SM) in the P-A format. Seven water utilities representing a wide geological and hydrological spectrum participated in the evaluation. A total of 702 split drinking water samples were analyzed. Of these, 358 were negative in both tests (SM- and AC-); 302 were positive (SM+ and AC+); and 42 were mixed (SM+ and AC-, 20; AC+ and SM-, 22). The overall agreement rate was 94%. Comparison of the SM and AC results by nonparametric statistics demonstrated no differences. Heterotrophic plate count bacteria exerted no discernible effect on the AC test. By subculture, each time the AC test was yellow, a total coliform was present; when the test was fluorescent, E. coli was isolated.

This article has been cited by other articles:

• Pisciotta, J. M., Rath, D. F., Stanek, P. A., Flanery, D. M., Harwood, V. J. (2002). Marine Bacteria Cause False-Positive Results in the Colilert-18 Rapid Identification Test for Escherichia coli in Florida Waters. Appl. Environ. Microbiol. 68: 539-544 [Abstract] [Full Text]  
• Eckner, K. F. (1998). Comparison of Membrane Filtration and Multiple-Tube Fermentation by the Colilert and Enterolert Methods for Detection of Waterborne Coliform Bacteria, Escherichia coli, and Enterococci Used in Drinking and Bathing Water Quality Monitoring in Southern Sweden. Appl. Environ. Microbiol. 64: 3079-3083 [Abstract] [Full Text]