Number Of Fecal Coliforms Research Articles

Seasonal changes in bacterial numbers and plant nutrients in point and non-point source ponds

The numbers of bacteria (total coliforms (TC), faecal coliforms (FC) and total aerobic bacteria (TAB) and nutrients (NH 4 +, NO 3 − and PO 4 −) in ponds receiving runoff from point and non-point sources were monitored at different seasons. Turbidity, BOD, pH and dissolved solids were measured. Neutral pH range (6·0–8·0) was observed in all the samples. In both ponds available nitrogen and phosphorus concentrations were significantly ( p<0·05) higher in sediment than in water. Lower temperatures in the winter correlated significantly ( p<0·05) with TAB, TC and FC bacteria. Nitrogen, especially NO 3, was also correlated ( p<0·05) with all bacterial (TAB, TC and FC) counts. However, PO 4 correlated negatively with the TC and FC in sediments and TC in surface water of both ponds. Faecal coliform numbers in the winter exceeded the recommended water quality standards.

Selective detection and enumeration of fecal coliforms in water by potentiometric measurement of lipoic acid reduction

Water samples of various origins were inoculated into a specific coliform-selective lactose broth provided with lipoic (thioctic) acid, and the time evolution of the redox potential of the cultures was monitored during incubation at 41 degrees C by use of gold versus reference electrodes. Positive potential-time responses, i.e., 100-mV potential shifts recorded within 20 h of inoculation, were related to the initial number of fecal coliforms in the broth determined by control enumeration techniques, and the organisms responsible were isolated and identified by conventional procedures. A total of 30 samples of wastewater, 38 of surface water, 553 of groundwater, and 110 of drinking water were tested successively. A total of 240 natural water samples, including 172 groundwater samples, and 1 drinking water sample were found to be positive in the potentiometric test. The majority (i.e., 92.5%) of the relevant potentiometric detection times were shorter than 15 h, and 96% of these could be attributed to Escherichia coli. Fifteen hours corresponded to the limit for detecting 1 E. coli cell per 100 ml of water. About 78% of the potentiometric responses occurring after 15 h were induced by fecal coliforms other than E. coli (Enterobacter cloacae, Klebsiella pneumoniae, and Citrobacter freundii). Calibration curves relating detection times shorter than 15 h to fecal coliform (i.e., E. coli) concentrations were constructed for the natural water samples tested. There were minor variations in the average growth rate of the organisms in the relation to the contamination level of the water tested. The number of false-positive samples in the potentiometric test was equivalent to that of false-negative samples (groundwater or drinking water).

Effects of Temperature and Storage Time on the Microflora, Sensory and Exudate Changes of Vacuum- or Nitrogen-Packed Beef

Beef chuck muscles from freshly slaughtered animals were vacuum- or nitrogen-packaged and stored at 0, 3 or 7°C in the dark. The effects of temperature, time, and atmosphere of storage on microflora, appearance, odor and exudate changes of vacuum and nitrogen package samples were examined at intervals during 49 days of storage. The microflora, sensory and exudate data at 0, 3 and 7°C showed highly significant differences due to the effect of temperature and storage time. Initially, the dominant flora of both package treatments consisted of Pseudomonas spp. (69.2%), but after 49 days the dominant flora became Lactobacillus spp. (51–55%). There was no significant change in numbers of total and fecal coli-forms at 3°C but coliforms constituted a significant part (max 103−105/g) of the microbial growth at 7°C, regardless of package types. Nitrogen gas packaging significantly improved the shelf-life of beef by retarding the development of discoloration and by minimizing the exudate losses.

Effect of Some Coal Gasification and Tar Sand Process Waters on the Viability of Indicator Bacteria of Fecal Contamination

AbstractThis research was undertaken to determine if a spill of either coal gasification or tar sand process waters could have detrimental effects on the numbers of indicator bacteria in receiving waters. The objectives were (i) to determine the effect of mixing process waters with “natural” waters on the numbers of fecal coliforms and fecal streptococci after storage of these mixtures at 4 and 20°C, (ii) to determine if the growth phase at the time of exposure was important to the survival of Escherichia coli, and (iii) to determine the importance of pH in the toxicity of a process water. Addition of 10% (vol/vol) of one coal gasification water to river water resulted in approximately 90% reduction in numbers of fecal coliforms within 5 h of storage at 4°C, whereas there was a 65% reduction during this time when storage was at 20°C. An additional coal gasification water and two tar sand process waters were not toxic to fecal coliforms. Survival of fecal streptococci was not adversely affected in any of the waters. Stationary phase cells of E. coli were killed within 5 h of exposure to a 10% concentration of Hanna IV B‐1 coal gasification water, whereas lag and exponential phase cells were unaffected during this exposure time. Further, after 24 h of exposure, 40% of the lag phase cells were viable, while live cells from the other two phases of growth were reduced by 99.9%. There was a 12% reduction in viable cells of E. coli after 120 h of exposure to a 10% concentration of Hanna IV B‐1 process water adjusted to pH 7.0. In contrast, during this same time period there was a 5 log reduction in viable cells that were exposed to the process water (pH 8.6), which had not been neutralized.

Effects of temperature and storage duration on the microflora, physicochemical and sensory changes of vacuum- or nitrogen-packed pork

A comparative study of vacuum packaging alone or vacuum followed by nitrogen back-flushing of fresh pork stored at −4, 0, 3 and 7°C for 49 days showed that pork stored at −4°C generally exhibited small changes in microbial numbers, pH, exudate, appearance and off-odour. Samples stored above 0°C could not be kept beyond 14–28 days without obvious changes, regardless of package atmospheres. Storage life was inversely related to temperature. The initial psychrotrophs consisted primarily of Pseudomonas spp. but these organisms diminished as Lactobacillus spp. multiplied in both atmospheres. Few significant differences in numbers of fecal coliforms were found between treatments, although the numbers tended to increase in samples stored at 7°C. Nitrogen packaging did not reduce exudate losses as compared with vacuum packaging.

Effects of a sewage lagoon effluent on the water quality of the receiving stream

The water quality of an activeky used small stream receiving the University of Ife sewage lagoon effluent was assessed down to 10 km below the pollution source. Faecal coliforms, total coliforms and heterotrophic bacteria were enumerated and the pH and dissolved oxygen values determined. Faecal coliform numbers in the region of the stream used to irrigate vegetables and farm crops in the dry season ranged from 10 5 to 10 6 100 ml −1 while populations as high as 10 2 to 10 4 100 ml −1 were obtained in the parts of the stream used for various domestic activities. Total coliform density ranged from 10 3 to 10 7 100 ml −1 in the actively used zone of the receiving stream. Furthermore, the total heterotrophic bacterial population of the receiving stream was raised from 10 4 to 10 8 ml −1 after mixing with the lagoon effluent, and was only reduced to about 10 5 ml −1 at 10 km downstream of the mixing point. The dissolved oxygen of the receiving stream dropped from 7·6 mg litre −1 to values less than 2 mg litre −1 on mixing with the effluent. The dissolved oxygen sag continued to 8 km downstream, after which detectable reaeration of the stream began. The various data strongly suggest that serious public health hazards could result from the use of this stream into which undisinfected sewage lagoon effluent is discharged.

Microbiological, physical and chemical studies of Livestock-farm water in Taiwan

The properties of drinking water from 42 hog farms, including pH, color, turbidity, total soluble solids, concentrations of ammonium nitrogen, nitrate nitrogen, nitrite nitrogen, chlorine, fluorine, sulphate, calcium, copper, zinc, iron, manganese and chromium were investigated. The total number of coliforms, fecal coliforms, fecal streptococci and standard plate counts of both drinking water and waste water were also studied. It was found that all the waste water and some of the drinking water was polluted. The major pollutant was hog feces. The culture counts of aerobic Gram-negative bacilli of fresh feces and fecal polluted water on one hog farm were examined in detail by using selective media. There were 364 strains of pure cultures isolated from MacConkey agar. The biochemical characteristics of the isolates on the triple sugar iron agar, Simmon's citrate agar, Christensen's urea agar, sulfide-indole-motility medium, Voges-Proskauer broth, Moller's ornithine decarboxylase medium, etc., were investigated. Microbial identification was carried out according to a computer-coding system based on the characteristics shown in the above media. The identified species were Escherichia coli (71%), Enterobacter agglomerans (6%), Enterobacter cloacae, Citrobacter freundii, Citrobacter diversus, Citrobacter amalonaticus, Aeromonas hydrophila, Arizona hinshawii, Vibrio sp., Hafnia alvei (Enterobacter hafniae), Chromobacterium violaceum, Yersinia enterocolitica, Plesiomonas shigelloides, Serratia liquefaciens, Pectobacterium sp., Proteus mirabilis, Edwardsiella tarda, Vibrio vulnificus, Provindencia rettgeri, Provindencia alcalifaciens, Proteus vulgaris, Klebsiella ozaenae, Klebsiella sp., Shigella sp., Morganella morganii, Serratia marcescens and Vibrio (EF-6) group F. The significance of these isolates for public health is discussed.

Quantitative Estimation of Fecal Coliforms in Fresh and Frozen Fishery Products by APHA and Modified A-1 Procedures

Fresh, frozen and breaded fish were analyzed for fecal coliforms by the modified A-1 (A-1 M) and APHA procedures. The A-1M method produced significantly lower numbers of fecal coliforms. The lower values derived by the A-1M procedure were attributed to the inhibiting effect of sample sediment on gas formation in fermentation tubes. By altering the A-1M technique, estimates comparable to those produced by the presently used APHA method were obtained. Changes consisted of an increase in incubation time at 44.5°C and/or elevating gas vials in the culture tubes.

Recovery of Selected Pathogens from Naples Bay, Florida, and Associated Waterways

The waters of Naples Bay, Florida, and associated waterways were monitored for potentially pathogenic bacteria, specificallyVibrio cholerae, V. parahaemolyticus, Salmonella, andPseudomonas aeruginosa. Ten to twelve stations were sampled over a period of eleven months.Vibrio cholerae was recovered in 33.6% of the 116 total samples andSalmonella in 28.4% of the samples. The results show that these bacteria exist in these waters and can be recovered from areas with both high and low numbers of total and fecal coliforms.

Venezuelan White Cheese: Composition and Quality

A survey was made at the retail level in the Venezuelan market to study the basic compositional and microbial characteristics of queso blanco, the most typical cheese in Venezuela. The commercial type labeled as pasteurizado blando “soft” was characterized by a high moisture content (50.6%), 2.5% sodium chloride, 21.4% fat and 19.2% protein, and a pH of 5.7. A second commercial type labeled as duro “hard” was characterized by lower moisture content (39%), 5.0% sodium chloride, 27.4% fat, 24.5% protein, and a pH of 5.3. Significant variation was found in these major compositional factors indicating a general lack of quality and/or extreme diversity of the manufacturing conditions used. Microbiological analysis revealed the presence of: (a) Salmonella, (b) extremely high numbers of total fecal coliforms and Escherichia coli, (c) high numbers of Staphylococcus aureus and enterotoxigenic S. aureus, and (d) other microorganisms including Bacillus cereus, Clostridium perfringens, Lactobacillus and yeast and molds. A statistical relationship between growth and numbers, and the presence of other indicators, pathogens, and compositional factors was investigated.

Bacteriological analysis of water by potentiometric measurement of lipoic acid reduction: preliminary assays for selective detection of indicator organisms.

The practical task of adapting an original potentiometric technique to the bacteriological analysis of water is discussed. Various laboratory strains of organisms belonging to the usual aquatic flora were inoculated one by one in a minimal lactose broth supplied with lipoic (thioctic) acid. The time evolution of the redox potential of the cultures was followed during incubation by combined gold versus reference electrodes. When the incubation temperature was regulated at 36 degrees C, most organisms were able to grow and to reduce the coenzyme, generating changes in the redox potential of the culture. However, very few organisms developed significant reductive activity when the temperature was increased to 41 degrees C and when the broth was provided with sodium deoxycholate. Among the fecal coliform organisms, only Escherichia coli and Klebsiella pneumoniae exhibited early but reproducible potential-time responses. Positive potentiometric responses were also recorded with Acinetobacter calcoaceticus. E. coli showed rapid potentiometric signals as compared with K. pneumoniae. The time required for 100-mV shift of potential to be detected was related to the logarithm of the initial concentration of E. coli or K. pneumoniae in the culture broth. Experiments on natural surface water samples showed the the potentiometric method, associated with the selective incubation conditions, mainly detected E. coli among the bacterial flora of the tested environmental water. The calibration curve relating the time required for a 100-mV shift of potential to be detected to the number of fecal coliforms, as determined by control fecal coliform-selective plate counts, was consistent with the composite standard curve of detection times obtained with six different laboratory strains of E. coli.(ABSTRACT TRUNCATED AT 250 WORDS)

Aerobic Mesophilic and Thermophilic Treatment of Piggery Wastes at Short Retention Times

ABSTRACT Aseries of intermittently fed 1.5 L digesters were used in this laboratory study to compare the effectiveness of aerobic treatment at temperatures of approximately 54 C, 46 C and 38 C. A positive level of dissolved oxygen was maintained during waste treatment while the retention time averaged about 1 day. The pH of un-treated effluents (total solids approximate 22 g/L) ranged from 7.4 to 7.8 while the pH in the treated ef-fluents averaged 7.0 at 54 C and 8.1 at 38 C. The mean 5 day biological oxygen demand (BOD5) of the un-treated wastes ranged from 7.8 to 9.8 g/L. Reductions in BOD5 were of the order 52 percent, 12 percent and 20 percent at 54 C, 46 C and 38 C respectively. Approx-imately 36 percent, 21 percent and 9 percent of volatile solids were oxidised during treatment, increasing with increasing temperature. The ABOD5/AVS ratios were 1.3, 0.3 and 0.8 for treatments at 38 C, 46 C and 54 C respectively. The numbers of faecal coliforms and faecal streptococci declined markedly during ther-mophilic treatment (T90 = 1.5 h) but were unaffected by treatment at either of the other lower temperatures.

Some effects of shoreline cottage development on lake bacteriological water quality

Eighteen cottaged lakes and one uncottaged lake in Southern Ontario, and their inflowing streams were surveyed for bacterial indicators of pollution by membrane filter techniques. Water samples were taken on 5 consecutive days in the spring, summer, and fall of the year. Inputs of fecal indicator bacteria were determined through an analysis of variance. Fecal coliform and fecal streptococcus levels in lakewater varied in a seemingly erratic manner. When the bacterial densities at different points on the lake were examined by an analysis of variance, the locations with significantly higher densities of fecal coliforms and fecal streptococci were most often found along the cottaged shoreline. Total coliform densities did not show this relationship with the cottaged shoreline. In addition, after rainfall, a large increase in numbers of fecal coliforms were found in the cottaged lakes but not in the uncottaged lake. These findings indicated that the cottaged shoreline was a greater source of fecal indicator bacteria than the uncottaged shoreline. However, the highest concentrations of fecal indicator bacteria in these lakes were found in the inflowing streams. The bacteria in these streams arose from stormwater from undeveloped forested watersheds and were probably, therefore, of soil or animal origin.

Relationship Between Land‐Use Practices and Fecal Bacteria in Soils

AbstractFecal and other bacteria populations in soils from pasture, cornfield, and forest sites were assessed at the Rhode River watershed. Total coliform (TC), fecal coliform (FC), total streptococci (TS), fecal streptococci (FS), and aerobic heterotrophic bacteria (TVC) numbers were determined seasonally. They were also determined with depth to 25 cm in soils from the pasture. Bacterial numbers per gram of pasture soil from the surface 1 cm were: 252‐1,603 TC, 10‐3% FC, 317‐2,270 TS, 163‐1,330 FS, and 1.6‐65.1 × 106 TVC. The numbers declined markedly with depth, except that TS and TVC numbers remained near the surface values. Fecal coliform numbers varied seasonally, from 22 to 396 MPN/g soil in fall and spring when cattle were grazing, and from 10 to 50 MPN/g soil in winter and summer when cattle were absent from the pasture. The cornfield and forest surface soils contained equally low FC numbers ranging from 3 to 27 MPN/g soil. Aerobic heterotrophic bacteria were similar in magnitude at all three land‐use sites. No readily discernable seasonal pattern was noted. The proportion of coliform bacteria differed with land use. In pasture soils 67% of isolates were confirmed as Escherichia coli, 22% were Enterobacter aerogenes, and 11% belonged to other species. In cornfield soils only 8% were E. Coli, 77% E. aerogenes, and 15% other species. In forest soils only E. coli were the dominant species. Thus, the pro‐ portion of E. coli was directly related to the degree of fecal pollution of the soils, and the proportion of E. aerogenes increased with remoteness of the soil from potential polluting agents.

Sand‐Filter Trenches for Purification of Septic Tank Effluent: III. The Microflora

AbstractThe microbial flora of sand filters play an important role in purification and clogging processes in sand. The organisms were studied by plate counts, microscopic counts, and biomass calculations. Fecal coliforms were estimated by MPN techniques.In sand‐filter trenches A, B, and C, operated at different temperatures and loading rates for further treatment of septic tank effluent, the number of viable bacteria in the infiltrative surface generally increased from 106 to 107–108/g sand, and was about 107 in the sandfill below. The total number of bacteria was a 100–1,000 times the viable count, and decreased with depth. This was most profound in a heavily clogged filter (A) which was kept at the highest temperature (12–15°C). Fecal coliform numbers followed the same pattern with depth.Rods (ca. 0.3 µm3) and cocci (ca. 0.06 and 0.5 µm3) dominated the bacterial flora of the sand‐filter trenches. Cocci (ca. 0.5 µm3) and small rods penetrated the whole profile in the least clogged unit, but were retained to a certain degree in unit A.In the crust layer of a heavily clogged sand filter, 44 mg C and 13 mg N/100 g sand were bound in bacteria. The bottom sand layers contained about 0.2 mg C and 0.006 mg N/100 g sand bound in the biomass. In a slightly clogged filter these values were about 40–50 times as high. In the most clogged unit the biomass was strongly correlated with the amount of total C. This was not the case in a slightly clogged unit.Concentrations of fecal coliforms in sand and outlet water from filters with low clogging intensities operated at ambient temperature were considerably higher than concentrations from a filter operated at a higher temperature and thus a higher clogging intensity.

Methaemoglobin levels in young children consuming high nitrate well water in the United States.

The EPA limit for nitrate (10 mg/l No3-N) in drinking water was established to prevent infantile methaemoglobinemia, an acute condition confined almost exclusively to infants less than three months. This condition is clinically detectable at methaemoglobin levels of approximately 10%. Several studies in the Soviet Union have suggested that elevated methaemoglobin levels from ingested nitrate may not be confined to the young infant and have reported an association between increased methaemoglobin levels of up to 7% in schoolchildren and drinking water with a nitrate concentration of 23-204 mg/l NO3-N. an epidemiologic study of 102 children aged 1-8 conducted in Washington County, Illinois, did not show that ingestion of water with a nitrate concentration of 22-111 mg/l NO3-N was related to increasing methaemoglobin levels nor that the children had high or above normal methaemoglobin levels. The potential for transmission of infections waterborne disease in this area was demonstrated, however, as a large percentage of the wells used for drinking water contained high numbers of total and faecal coliforms.

Relationships between environmental factors, bacterial indicators, and the occurrence of enteric viruses in estuarine sediments.

Current standards for evaluation of the public health safety of recreational and shellfish-harvesting waters are based upon bacteriological analysis, but do not include an evaluation of the number of viruses. The objective of this study was to determine the occurrence of enteric viruses in estuarine sediments and to find a relationship, if any, between the presence of viruses in seawater or sediment or both and various biological and physicochemical characteristics of the environment. Viruses were found in greater numbers in sediment than in overlying seawater on a volume basis. Several types of enteroviruses were isolated: coxsackievirus types A16, B1, and B5, echovirus type 1, and poliovirus type 2. On several occasions, viruses were isolated from sediments when overlying seawaters met bacteriological water quality standards for recreational use. Statistical analysis of the relationship between viruses in seawater or in sediment and other variables measured yielded only one significant association: the number of viruses in sediment was found to be positively correlated with the number of fecal coliforms in sediment. No other physical, chemical, or biological characteristic of seawater or sediment that was measured showed statistically significant association with viral numbers. No correlation was found between bacterial indicators and virus in the overlying waters. The data indicated that evaluation of the presence of bacteria and viruses in sediment may provide additional insight into long-term water quality conditions and that indicator bacteria in water are not reflective of the concentration of enteric viruses in marine waters.

The Effect of Cadmium on Indicator Bacteria in Sewage

The effect of cadmium (Cd) on the number of different faecal indicator bacteria in sewage, and on species composition of different indicator bacteria, was studied. Different amounts of Cd were added to aliquots of a sewage sample, and after 0, 4% and 24 h of Cd exposure at 20°C conforms, faecal coliforms, faecal streptococci and Clostridium perfringens were enumerated by the membrane filter method. The Cd-induced reduction in the number of coliforms and faecal coliforms during exposure was found to be greater than the decrease in the number of faecal streptococci. In the case of C. perfringens the Cd concentrations used produced no observable effect on the cell number. The addition of Cd changed the faecal coliforms and faecal streptococci density relationship. Escherichia coli seems to be more resistant to Cd than other coliforms and Streptococcus faecalis var. liquefaciens and Streptococcus durans more resistant to Cd than other faecal streptococci. No influence of Cd on gas production by faecal coliforms was observed. Faecal streptococci and C. perfringens seem to be better indicator bacteria than coliforms and faecal coliforms in evaluating the hygienic quality of Cd polluted sewage.

Natural Enterovirus and Fecal Coliform Contamination of Gulf Coast Oysters

The numbers of fecal coliforms and enteroviruses present in oysters and/or their growing waters of two Mississippi reefs were determined over a 12-month period. Bacterial and viral levels reflected the classification of the waters at each location as set by the Mississippi State Board of Health in compliance with the National Shellfish Sanitation Program, but statistically significant correlations between these levels were not observed. Twelve viral isolates were found at an approved oyster harvesting location, eight of which were identified as poliovirus type 1. At the prohibited site, 146 viruses were isolated including poliovirus types 1 and 2, echovirus type 24 and several isolates which remain to be identified. The number of virus isolates from samples from each location represented approximately 35% of the number of plaques observed; however, no consistent ratio of plaque to confirmed virus was demonstrated. The results suggest that the fecal coliform levels in oyster growing waters do not reflect the level of virus contaminaton in either approved or prohibited waters.

Destruction by Anaerobic Mesophilic and Thermophilic Digestion of Viruses and Indicator Bacteria Indigenous to Domestic Sludges

In raw sludges and in mesophilically and thermophilically digested anaerobic sludges, large variations in numbers of viruses occurred over narrow ranges of numbers of fecal coliforms, total coliforms, and fecal streptococci, demonstrating that the bacteria were poor quantitative reflectors of the numbers of the viruses detected. Mesophilic and thermophilic digestion of anaerobic sludges destroyed all three indicator bacteria more rapidly than such digestion destroyed the viruses. The relative rates for the destruction of viruses, fecal coliforms, and fecal streptococci in the digested sludges were consistent over the 17-month study. Fecal coliforms were 7 to 8 times more sensitive than the viruses to mesophilic digestion and 9 to 10 times more sensitive to thermophilic digestion. Total coliforms were even more sensitive. The rates at which fecal streptococci were destroyed by mesophilic and thermophilic digestion of anaerobic sludges approached those at which the viruses were destroyed by those processes; this suggested that the rates at which fecal streptococci in sludges are destroyed by those processes may serve as useful indicators for the rates at which viruses in sludges are destroyed by those processes.