Topic
Coliform index
About: Coliform index is a research topic. Over the lifetime, 120 publications have been published within this topic receiving 3735 citations.
Papers published on a yearly basis
1 / 2
Papers
TL;DR: Comparison with other practical candidate fecal indicators shows that E. coli is far superior overall, and under most circumstances it is possible to design a monitoring program that permits public health protection at a modest cost.
Abstract: Public health protection requires an indicator of fecal pollution. It is not necessary to analyse drinking water for all pathogens. Escherichia coli is found in all mammal faeces at concentrations of 10 log 9(-1), but it does not multiply appreciably in the environment. In the 1890s, it was chosen as the biological indicator of water treatment safety. Because of method deficiencies, E. coli surrogates such as the 'fecal coliform' and total coliforms tests were developed and became part of drinking water regulations. With the advent of the Defined Substrate Technology in the late 1980s, it became possible to analyse drinking water directly for E. coli (and, simultaneously, total coliforms) inexpensively and simply. Accordingly, E. coli was re-inserted in the drinking water regulations. E. coli survives in drinking water for between 4 and 12 weeks, depending on environmental conditions (temperature, microflora, etc.). Bacteria and viruses are approximately equally oxidant-sensitive, but parasites are less so. Under the conditions in distribution systems, E. coli will be much more long-lived. Therefore, under most circumstances it is possible to design a monitoring program that permits public health protection at a modest cost. Drinking water regulations currently require infrequent monitoring which may not adequately detect intermittent contamination events; however, it is cost-effective to markedly increase testing with E. coli to better protect the public's health. Comparison with other practical candidate fecal indicators shows that E. coli is far superior overall.
990 citations
TL;DR: The role that coliforms play in raw and finished dairy products, their sources and the future of this diverse group of bacteria as indicator organisms in dairy products are addressed.
Abstract: Testing for coliforms has a long history in the dairy industry and has helped to identify raw milk and dairy products that may have been exposed to unsanitary conditions. Coliform standards are included in a number of regulatory documents (e.g., the U. S. Food and Drug Administration’s Grade “A” Pasteurized Milk Ordinance). As a consequence, detection above a threshold of members of this method-defined, but diverse, group of bacteria can result in a wide range of regulatory outcomes. Coliforms are defined as aerobic or facultatively anaerobic, Gram negative, non-sporeforming rods capable of fermenting lactose to produce gas and acid within 48 hours at 32-35°C; 19 genera currently include at least some strains that represent coliforms. Most bacterial genera that comprise the coliform group (e.g., Escherichia, Klebsiella and Serratia) are within the family Enterobacteriaceae, while at least one genus with strains recognized as coliforms, Aeromonas, is in the family Aeromonadaceae. The presence of coliforms has long been thought to indicate fecal contamination, however, recent discoveries regarding this diverse group of bacteria indicates that only a fraction are fecal in origin, while the majority are environmental contaminants. In the US dairy industry in particular, testing for coliforms as indicators of unsanitary conditions and post-processing contamination is widespread. While coliforms are easily and rapidly detected, and are not found in pasteurized dairy products that have not been exposed to post-processing contamination, advances in knowledge of bacterial populations most commonly associated with post-processing contamination in dairy foods has led to questions regarding the utility of coliforms as indicators of unsanitary conditions for dairy products. For example, Pseudomonas spp. frequently contaminate dairy products after pasteurization, yet they are not detected by coliform tests. This review will address the role that coliforms play in raw and finished dairy products, their sources and the future of this diverse group as indicator organisms in dairy products.
189 citations
TL;DR: The use of Escherichia coli as an indicator of fecal pollution and the significance of its presence in surface waters was reviewed and a minidefinition which identifies this organism at least 95 percent of the time was proposed.
Abstract: The use of Escherichia coli as an indicator of fecal pollution and the significance of its presence in surface waters was reviewed. A minidefinition which identifies this organism at least 95 percent of the time was proposed. Membrane filtration and most probable number methods for the enumeration of E. coli were discussed.
180 citations
TL;DR: In this study, the in-mill water and external effluent treatment systems of seven typical Canadian pulp and paper mills were all shown to support the growth of numerous coliforms, especially Klebsiella Spp.
102 citations
Book•
5 Dec 1996
TL;DR: The significance of emerging pathogens on water quality assessment and the use of gene probes and PCR to detect coliforms in water are illustrated.
Abstract: Preface. Microbial water quality: Introduction. The evolution of sanitary science. Waterborne outbreaks. Public health significance. Sources of waterborne disease. Risk assemssment. Legislation governing microbial water quality. Conclusions. Indicator organisms and the 'coliform concept': The origins of indicator organisms. The development of coliform as indicator organisms. Coliforms as indicators of water quality. The relevance of coliforms and faecal coliforms as faecal indicators in tropical conditions. The use of faecal coliforms as opposed to total coliforms. Conclusions. Evaluation of standard methods for the enumeration of coliforms from drinking waters: The multiple tube method (most probable number method). The membrane filtration method. Conclusions. Alternative techniques for the isolation and enumeration of coliforms and E. coli from drinking water: The presence-absence technique. Defined substrate technology (enzyme detection methods). Rapid methods. Immunodiagnostic techniques. The use of gene probes and PCR to detect coliforms in water. Conclusions. Alernative indicator systems for water quality analysis: Faecal streptococci. The faecal coliform/faecal streptococci (FC/FS) ratio. Clostridia perfringens. Bacteriophage. Bifidobacteria. Rhodococcus spp. Heterotrophic plate count bacteria. Other indicator organisms. Alternative indicators for tropical environments. Chemical indicators. Conclusions. The significance of emerging pathogens on water quality assessment: Giardia lamblia. Cryptosporidium spp. Viruses. Bacteria. Conclusions. The future of the coliform index: Introduction. The Coliform Index today. Future action. Final analysis. References. Index.
99 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2020 | 1 |
| 2017 | 2 |
| 2016 | 6 |
| 2015 | 4 |
| 2014 | 8 |
| 2013 | 2 |