Improving the assessment of risk from pathogens in biosolids: fecal coliform regrowth, survival, enumeration, and assessment

Reactivation or regrowth of fecal coliform bacteria in biosolids has recently become a concern due to knowledge that Class B materials may fail to meet this criterion after storage or even after land application. In this paper, data show the two types of fecal coliform increases that have been characterized: immediate reappearance of large concentrations directly after dewatering; and the rapid, but less immediate, increases that follow dewatering with some biosolids after dewatering. The latter phenomenon is shown to extend over a time period of days prior to gradual decrease in fecal coliform numbers. Modeling shows that anaerobic or fermentative growth cannot simulate the observed growth, but that a straightforward biokinetic model can duplicate the observed conditions if a doubling time of one hour is assumed, which is supported by literature. Thus regrowth cannot be ruled out as the underlying phenomenon

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Reactivation and/or growth of fecal coliform bacteria during centrifugal dewatering of anaerobically digested biosolids

Water Science & Technology ◽

10.2166/wst.2004.0549 ◽

2004 ◽

Vol 50 (9) ◽

pp. 115-120 ◽

Cited By ~ 8

Author(s):

Y.N. Qi ◽

S. Gillow ◽

D.S. Herson ◽

S.K. Dentel

Keyword(s):

Fecal Coliform ◽

Treatment Plant ◽

Land Application ◽

Fecal Coliforms ◽

Coliform Bacteria ◽

Human Pathogens ◽

Indicator Organisms ◽

Treatment Facility ◽

Fecal Coliform Bacteria ◽

Media Type

Fecal coliform bacteria are used as indicator organisms for the presence of pathogens. In sludges, it has often been assumed that the counts of fecal coliforms after digestion (where the sludges may also be called biosolids) are representative of the counts when the sludge is disposed or recycled, such as by land application. The possibility has been raised, however, that dewatering processes can lead to increased counts of fecal coliforms and, by inference, human pathogens. This paper presents data from previous studies of this possibility; the results were inconsistent but showed observable increases in fecal coliforms at one treatment plant. Additional studies were then performed at another treatment facility, which showed statistically significant increases in fecal coliform counts after dewatering and two days of aging. The increases exceeded two orders of magnitude and included two centrifuge types and two biosolids types. Artifacts of media type and enumeration method have been excluded, and shearing of the material by commercial blender did not produce the same effects.

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Analysis of Fecal Coliform Bacteria in Spring Creek above Sheridan Lake in the Black Hills of South Dakota

Impacts of Global Climate Change ◽

10.1061/40792(173)155 ◽

2005 ◽

Author(s):

Patrick Schwickerath ◽

Thomas Fontaine ◽

Scott Kenner

Keyword(s):

South Dakota ◽

Fecal Coliform ◽

Black Hills ◽

Coliform Bacteria ◽

Fecal Coliform Bacteria

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Analysis of Coliform and Colifecal Total Pollution Test on Various Types of Drinking Water Using the MPN (Most Probable Number) Method

Serambi Journal of Agricultural Technology ◽

10.32672/sjat.v2i2.2416 ◽

2020 ◽

Vol 2 (2) ◽

Author(s):

Wanda Aulya ◽

Fadhliani Fadhliani ◽

Vivi Mardina

Keyword(s):

Drinking Water ◽

Fecal Coliform ◽

Pathogenic Bacteria ◽

Microbiological Quality ◽

Coliform Bacteria ◽

Most Probable Number ◽

Inspection Method ◽

Sample Number ◽

Probable Number ◽

Fecal Coliform Bacteria

Water is the main source for life and also the most severe substance caused by pollution. The mandatory parameters for determining microbiological quality of drinking water are total non-fecal Coliform bacteria and Coliform fecal (Escherichia coli). Coliform bacteria are a group of microorganisms commonly used as indicators, where these bacteria can be a signal to determine whether a water source has been contaminated by bacteria or not, while fecal Coliform bacteria are indicator bacteria polluting pathogenic bacteria originating from human feces and warm-blooded animals (mammals) . The water inspection method in this study uses the MPN (Most Probable Number) method which consists of 3 tests, namely, the presumption test, the affirmation test, and the reinforcement test. The results showed that of 15 drinking water samples 8 samples were tested positive for Coliform bacteria with the highest total bacterial value of sample number 1, 15 (210/100 ml), while 7 other samples were negative. From 8 positive Coliform samples only 1 sample was stated to be negative fecal Coliform bacteria and 7 other samples were positive for Coliform fecal bacteria with the highest total bacterial value of sample number 1 (210/100 ml).

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