The utility of the AC/TC ratio for watershed management: a case study

2004 ◽  
Vol 50 (1) ◽  
pp. 199-203 ◽  
Author(s):  
J. Booth ◽  
G.M. Brion
Keyword(s):  
Watershed Management ◽  
Membrane Filter ◽  
Total Coliform ◽  
Faecal Coliforms ◽  
Faecal Material ◽  
Total Coliforms ◽  
Filter Assay ◽  
The Impact ◽  
Faecal Streptococci

A human-impacted watershed was monitored during the dry summer seasons in 2002 and 2003 to investigate the impact of providing access to sewer mains to local village residences. Faecal coliform concentrations were monitored at select sites along the 30-mile stretch of creek, together with faecal streptococci, enterococci and total coliforms. Analysis of the results found that levels of faecal coliforms were inadequate at identifying significant known influxes of human and animal sewage established by sanitary survey. However, the bacterial ratio of atypical colonies to total coliform colonies (AC/TC), obtained from the total coliform membrane filter assay on m-Endo media, correctly indexed human faecal impact of inadequately sewered villages located along the creek. In addition, the AC/TC ratio correctly classified the predominant source of faecal runoff in the creek headwaters as agricultural, and indicated when aged agricultural faecal material was introduced by tributaries. An approach for watershed management that uses the AC/TC ratio in addition to levels of bacteria is proposed.

The influence of increasing numbers of nonindicator organisms upon the detection of indicator organisms by the membrane filter and presence–absence tests

1980 ◽  
Vol 26 (7) ◽  
pp. 827-832 ◽  
Author(s):  
James A. Clark
Keyword(s):  
Membrane Filter ◽  
Total Coliform ◽  
Plate Count ◽  
Indicator Organisms ◽  
Isolation Technique ◽  
Total Coliforms ◽  
Inhibition Effect ◽  
Counting Range ◽  
Plate Counts ◽  
Better Than

Municipal water samples were analyzed by membrane filter (MF) procedures for total coliforms, "background" counts, and 24-and 48-h, 35 °C plate counts. Presence–absence (P–A) tests were done on the samples for total coliforms and other indicator bacteria. The frequency of detection of indicator organisms by P–A tests was better than twice that recovered by MF analyses. When the 24-h plate count data were grouped into counting ranges of 0, 1–100, 101–1000, and > 1000, a marked inhibition effect was observed with total coliform MF recoveries on samples producing plate counts > 1000/mL. When the "background" and 48-h plate count results were placed in the corresponding counting ranges, inhibition of indicator organisms in the total coliform MF analyses was not observed. No inhibition effect was observed in the recovery of indicator organisms by P–A tests at any of the counting range levels. The presence of an apparent inhibition effect by high numbers of bacteria in a sample was shown to be influenced by the incubation period and type of count parameter, as well as the isolation technique for detection of indicator organisms.

Removal of indicator bacteria from municipal wastewater in an experimental two-stage vertical flow constructed wetland system

2003 ◽  
Vol 48 (5) ◽  
pp. 35-41 ◽  
Author(s):  
C.A. Arias ◽  
A. Cabello ◽  
H. Brix ◽  
N.-H. Johansen
Keyword(s):  
Constructed Wetland ◽  
Rate Constants ◽  
Indicator Bacteria ◽  
Vertical Flow ◽  
Faecal Coliforms ◽  
Total Coliforms ◽  
Sedimentation Tank ◽  
Vertical Flow Constructed Wetland ◽  
Wetland System ◽  
Faecal Streptococci

The removal of sanitary indicator bacteria (total coliforms, faecal coliforms, and faecal streptococci) was studied in an experimental constructed wetland system consisting of (1) a 2-m3 three-chamber sedimentation tank, (2) a 5 m2 vertical flow constructed wetland, (3) a filter-unit with calcite aimed at removing phosphorus, and (4) a 10 m2 vertical flow constructed wetland. The indicator bacteria were enumerated before and after each unit of the wetland system during four monitoring episodes with different loading conditions. At a hydraulic loading rate of 520-1,370 mm/d, the first-stage vertical flow beds removed about 1.5 log-units of total coliforms, 1.7 log-units of faecal coliforms and 0.8 log-units of faecal streptococci. In the second stage bed receiving lower loadings both in term of concentration and quantity (260-690 mm/day), the eliminations were lower. It was not possible in the present study to identify any seasonal effects, but no measurements were done during summer. Recycling of treated effluent back to the sedimentation tank did not affect elimination. Area-based rate constants for the vertical flow wetland receiving effluent from the sedimentation tank averaged 3.2 m/d for total coliforms, 3.3 m/d for faecal coliforms and 2.1 m/d for faecal streptococci. The rate constants depended on loading rates. It is suggested that filtration is a major removal mechanism for bacterial indicator organisms in vertical flow constructed wetland systems.

Enumeration of Total Coliforms, Fecal Coliforms, and Escherichia coli in Foods by Hydrophobic Grid Membrane Filter: Supplementary Report

1984 ◽  
Vol 67 (4) ◽  
pp. 811-812
Author(s):  
Phyllis Entis
Keyword(s):  
Escherichia Coli ◽  
Membrane Filter ◽  
Total Coliform ◽  
Fecal Coliforms ◽  
Poultry Meat ◽  
Filter Method ◽  
Total Coliforms ◽  
The Media ◽  
Aoac Method ◽  
Membrane Filter Method

Abstract Raw, comminuted poultry meat was used to determine the specificity of the media and incubation conditions used in the hydrophobic grid membrane filter method. Confirmation rates for target colonies were 100% for total coliforms, 98% for fecal coliforms, and 97-99% for Escherichia coli. The results of total coliform enumeration in 30 pasteurized milk samples by both the hydrophobic grid membrane filter method and AOAC method 46.013-46.016 are also reported.

Wastewater quality improvement through storage: a case study in Sicily

2003 ◽  
Vol 47 (7-8) ◽  
pp. 169-176 ◽  
Author(s):  
S. Barbagallo ◽  
G. Luigi Cirelli ◽  
S. Consoli ◽  
F. Somma
Keyword(s):  
Removal Efficiency ◽  
Secondary Treatment ◽  
Faecal Coliforms ◽  
Reservoir Design ◽  
Wastewater Quality ◽  
Operation Parameters ◽  
Design Characteristics ◽  
Faecal Streptococci ◽  
Influent Wastewater

This paper presents the results of a research aiming at evaluating the effects of storage on wastewater characteristics. Wastewater discharged from the Caltagirone (Eastern Sicily) plant after secondary treatment was stored in an earth reservoir with a capacity of about 25,000 m3 and a depth of 5 m. Wastewater inflow in the reservoir was continuos throughout the experimental activities, while discharge was discontinuous, depending on irrigation demand. Removal efficiency resulted highly influenced by the operation regime of the reservoir and by influent wastewater characteristics. BOD5 and COD removal efficiency was above 50%. Removal efficiency of faecal coliforms, faecal streptococci and Escherichia coli was between 2 and 5 log units. Single and multiple regressions were tested to determine the reservoir design characteristics and operation parameters that most significantly affected water quality changes.

scholarly journals ESTUDIO DE ALGUNOS ASPECTOS ECOLOGICOS Y DE LA CONTAMINACION BACTERIANA EN LA BAHIA DE SANTA MARTA, CARIBE COLOMBIANO

2016 ◽  
Vol 18 ◽  
Author(s):  
Alfonso Escobar Nieves
Keyword(s):  
Rainy Season ◽  
Abiotic Factors ◽  
Faecal Coliforms ◽  
Recreational Waters ◽  
Sewage Discharge ◽  
Total Coliforms ◽  
Biochemical Identification ◽  
Identification Of Bacteria ◽  
Lower Limits ◽  
Faecal Streptococci

The fecal contamination of the Bay of Santa Marta was investigated between July 1979 and March 1980. The organisms used were total coliforms, faecal coliforms and faecal streptococci. Abiotic factors such as temperature, salinity and water transparency were also measured. The presence of Sdmonella in recreational waters was investigated sporadically. The results of this study have indicated severe contamination in the port zone (station 5), the mouth of Manzanares river (station 11), and around the Boquerón sector (station 22), where the raw sewage is discharged . Significant values of total coliforms above the international standard lower limits were detected at themunicipal beach (station 10) during the rainy season months. The levels of total coliforms fluctuated betwwn 0 and 1.4x10t colonies/ml. The biochemical identification of bacteria of the genus Salmonella gives evidence for the potencial danger that exists,at the bathing sectors near the sewage discharge sites.

scholarly journals EnterotoxigenicEscherichia coliin the domestic environment of a Malaysian village

1989 ◽  
Vol 103 (3) ◽  
pp. 497-511 ◽  
Author(s):  
J. Vadivelu ◽  
R. G. Feachem ◽  
B. S. Drasar ◽  
T. J. Harrison ◽  
N. Parasakthi ◽  
...  
Keyword(s):  
Dna Hybridization ◽  
Membrane Filter ◽  
Food Samples ◽  
Food Preparation ◽  
Hybridization Assay ◽  
Faecal Coliforms ◽  
Weaning Food ◽  
Stool Samples ◽  
Filter Assay ◽  
Children Under 5

SUMMARYThe membrane-filter assay, GM1-ELISA, and DNA-DNA hybridization assay, were used to detect enterotoxigenicEscherichia coli(ETEC) in samples of water, weaning food, food preparation surface swabs, fingerprints of mothers, and the fingerprints and stools of children under 5 years of age, in 20 households in a Malaysian village. Weaning food and environmental samples were frequently contaminated by faecal coliforms, including ETEC. The membrane-filter assay detected and enumerated faecal coliforms and LT-ETEC in all types of water and weaning food samples. Highest concentrations of faecal coliforms and LT-ETEC were found in weaning food, followed by well-water, stored water and stored drinking water. The GM1-ELISA detected LT-ETEC in weaning food, food preparation surfaces, fingerprints and stool samples. The DNA-DNA hybridization assay detected a larger proportion of STa2-ETEC than the other toxotypes, either singly or in combination. All the assays in combination detected the presence of ETEC in all types of samples on at least one occasion in each household. It was not possible to classify households as consistently more or less contaminated with ETEC. On individual occasions it was possible to show a significant association of the presence of LT-ETEC between the fingerprints of children and their stools, fingerprints of mothers and children, and weaning food and the stools of the child consuming the food.

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