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PubMedDate not supplied

The dissipation of phosphorus in sewage and sewage effluents.

Of the 41 kt of phosphorus reaching the sewage works in England and Wales 15 kt is removed in sewage sludge and the remainder is disposed of to rivers. 60% of the sewage sludge is now used as fertilizer and this proportion will no doubt increase in the future. The total use of sewage sludge, however, represents only about 5% of the current annual usage of artificial phosphorus fertilizer. At present there is no general economic incentive to make better use of the phosphorus in effluents. Phosphorus removal is expensive--about 2--3 pence/m3. If all the sewage effluents in England and Wales were to be so treated the cost would be about 100--150 million pounds annually, that is about 50% of the present costs of sewage treatment. In certain cases, but rarely in the UK, phosphate is removed, not to conserve phosphorus but to minimize the problems it creates in the environment. The phosphorus removed has little value as fertilizer. Alternative methods of using the phosphorus in effluents by the production and harvesting of crops of algae or aquatic plants have so far proved uneconomic. However, these methods need to be reviewed periodically as they may in the future become economically more attractive, especially in warmer climates where plant growth can be maintained throughout the year.

Adult↗

PubMedDate not supplied

[Importance of the results of a virological examination of sewage. A quantitative evaluation of the finding of enteroviruses in sewage].

In order to evaluate quantitatively the effectiveness of virological examinations of sewage, a labeled virus in a dose of 7.5X10(9) PFU was introduced into the canalization system of a community. Such an amount of virus could be found in the canalization system if 5--10% of the residents would excrete it simultaneously. The labeled virus was selectively detected in the community sewage. This procedure has demonstrated that the routine methods for sewage collection, specimen treatment, and virus isolation permit virus detection when 5--10% of this virus excretors are available. The labeled virus entered the canalization system most actively within the first 2 hours after administration, then its amount declined, and within 24 hours ceased. The labeled virus was found on all swabs which were in the sewage flow since the time of administration to the 7th day. The maximum amount of virus was found on the swab which was in the sewage flow for the first 2 hours after virus administration. By 7 days the amount of labeled virus on swabs decreased 10-fold. Under experimental conditions, in sewage kept at 25 degrees C enteroviruses of the group of poliomyelitis, ECHO, and Coxsackie had approximately similar inactivation rate (0.16--0.22 Ig TCD50 per day) and the half-life period (1.3 days), that is, in 7 days the virus titer on a swab should decline by 1.0--1.5 Ig TCD50.

Enterovirus↗

PubMedDate not supplied

[Importance of the results of a virological examination of sewage. A comparison of the series of enteroviruses isolated from sewage and from the feces of virus excreters].

Simultaneous examinations for the presence of enteroviruses were carried out on sewage of the central aeration station, periferal collectors of the most populous institutions, preschool children's institutions as well as feces of children attending these institutions in a community of urban type. A high degree of coincidence of spectra of enteroviruses isolated from sewage of the central station, periferal collectors, sewage of children's institutions, and from the feces of most virus excretors was demonstrated. No enteroviruses found in occasional virus excretors were detected in sewage. Enteroviruses were regularly found in sewage of periferal collectors if approximately 10% of children excreted a certain virus type simultaneously.

Carrier State↗

PubMed1979

[Epidemiological studies on Salmonella in a particular area ('Walcheren Project'). IV. The incidence of Salmonella in the sewage system, in faeces of man and pets as well as in shops, kitchens and lavatories in the village of Aagtekerke (author's transl)].

As part of the epidemiological investigations on Salmonella on the island of Walcheren, the contamination of sewage water in the village of Aagtekerke was studied over a prolonged period. These studies showed that this sewage water was frequently contaminated by large numbers of Salmonella. In the present study, efforts were made to find an answer to the question of the origins of this contamination. For this purpose, the incidence of Salmonella in the sewage system, in faeces of man and pets as well as in shops, kitchens and lavatories in the village of Aagtekerke was studied for a period of three weeks in June 1977. In addition to the findings in the sewage system (including the inlet water and effluents of the sewage works) which were positive for Salmonella, this organism was only isolated from a few faecal samples of human and animal origin. Serotyping showed that the strains isolated from human faeces were similar to those found to be present in the sewage system. This fact, in conjunction with the results of the bacterial counts. suggests that the sewage system was only contaminated by the small number of carriers. The reduction of contamination observed in the sewage system during the period of investigation could be evidence of the fact that Salmonella organisms cannot survive by themselves in an environment of this type, at least not at the temperatures recorded on collecting samples from the sewage water. Growth of organisms under more favourable conditions cannot be ruled out. An inquiry on dietary habits and kitchen hygiene of the local population showed that contamination within households. Origination with the food, is a real possibility.

Adult↗

PubMed2025

Novel Bacteroides bacteriophage-like quantitative real-time PCR assays for human sewage pollution measurement.

A recent study reports the genome sequence of ΦB124-14, a bacteriophage capable of infecting a narrow subset of Bacteroides spp. closely associated with the human gut. To investigate the use of ΦB124-14 for fecal source identification applications, the genome was interrogated for human-associated genetic regions using bioinformatic and laboratory approaches. Fifty-three primer sets were tested using 100 fecal samples from ten animal sources, primary influent sewage from 36 geographical locations across the United States, and environmental surface waters with known human sewage impact. Based on candidate primer set end-point PCR analyses and next generation amplicon sequencing, two novel quantitative real-time PCR assays (qPCR), PS28 and PS30, were designed and evaluated. Both qPCR assays exhibited a sensitivity of 86.1 %, a specificity of 100 %, and successfully detected ΦB124-14-like genetic markers in sewage impacted environmental water samples. PS28 and PS30 performance was then compared to established DNA-based viral (CPQ_056 and CPQ_064) and bacterial (HF183/BacR287 and HumM2) human-associated qPCR assays. Findings indicated ΦB124-14 bacteriophage-like qPCR assays exhibited superior specificity, but markers consistently occurred at lower concentrations in United States primary influent sewage. Reduced sensitivity may be insufficient for application in U.S. environmental waters, especially when trace levels of sewage are present. Furthermore, paired measurements of ΦB124-14 and crAssphage bacteriophage-like sequences in high volume (10 L) primary influent sewage samples (n = 38) indicated significant correlations ranging from r = 0.593 (p < 0.0001; PS30 versus CPQ_056) to r = 0.938 (p < 0.0001; PS28 versus PS30). A comparison of bacteriophage-like marker concentrations with cultured GB-124 in sewage samples showed no significant correlations (r ≤ 0.215, p ≥ 0.183).

Sewage↗

PubMed1977

Comparison of poliovirus detection in sewage and stool samples; a study in a crèche in the third week after vaccination.

In a model experiment conducted in a Prague crèche, the detection rate for polioviruses in partially purified, non-concentrated sewage as sampled by means of gauze pads (Moore's method) was compared with that for individual stool samples. In the third week after the vaccination of children with live attenuated type 1 poliovirus (March 1975) and at an equal interval after their vaccination with a combination of types 2 and 3 (May 1975), corresponding poliovirus types were detected both in individual stool samples and sewage. The mean amount of sewage virus recovered during one week was directly proportional to the percentage of positive stool samples. After combined type 2 and 3 poliovirus administration, however, both types were only detected in one sewage sample, while in two samples type 3 only, and in one sample type 2 only, were identified. The results of the study indicate that poliovirus is detectable in sewage by the method employed if it is excreted by approximately one per cent of persons in the sewer catchment area of a small community. If a number of antigenic types are simultaneously present, their identification requires systematic examination of the sewage.

Adult↗

PubMed1976

Virus movement in soil columns flooded with secondary sewage effluent.

Secondary sewage effluent containing about 3 X 10(4) plaque-forming units of polio virus type 1 (LSc) per ml was passed through columns 250 cm in length packed with calcareous sand from an area in the Salt River bed used for ground-water recharge of secondary sewage effluent. Viruses were not detected in 1-ml samples extracted from the columns below the 160-cm level. However, viruses were detected in 5 of 43 100-ml samples of the column drainage water. Most of the viruses were adsorbed in the top 5 cm of soil. Virus removal was not affected by the infiltration rate, which varied between 15 and 55 cm/day. Flooding a column continuosly for 27 days with the sewage water virus mixture did not saturate the top few centimeters of soil with viruses and did not seem to affect virus movement. Flooding with deionized water caused virus desorption from the soil and increased their movement through the columns. Adding CaCl2 to the deionized water prevented most of the virus desorption. Adding a pulse of deionized water followed by sewage water started a virus front moving through the columns, but the viruses were readsorbed and none was detected in outflow samples. Drying the soil for 1 day between applying the virus and flooding with deionized water greatly reduced desorption, and drying for 5 days prevented desorption. Large reductions (99.99% or more) of virus would be expected after passage of secondary sewage effluent through 250 cm of the calcareous sand similar to that used in our laboratory columns unless heavy rains fell within 1 day after the application of sewage stopped. Such virus movement could be minimized by the proper management of flooding and drying cycles.

Adsorption↗

PubMed1975

Survival of human enteric and other sewage microorganisms under simulated deep-sea conditions.

The survival of pure cultures of Escherichia coli, Streptococcus faecalis, Clostridium perfringens, and Vibrio parahaemolyticus under simulated deep-sea conditions of low temperature (4 C), seawater, and hydrostatic pressures ranging from 1 to 1,000 atm was determined over a period exceeding 300 h. The viability of E. coli and total aerobic bacteria in seawater-diluted raw sewage subjected to these deep-sea conditions was also measured. There was a greater survival of both E. coli and S. faecalis at 250 and 500 atm than at 1 atm at 4 C. S. faecalis was quite insensitive to 1,000 atm, whereas with E. coli there was a 10-fold die-off per 50-h exposure to 1,000 atm. In contrast, V. parahaemolyticus and C. perfringens were quite sensitive to pressures exceeding 250 atm, and with both of these species there was a total loss of viability of approximately 10(8) cells per ml within 100 h at 1,000 arm and within 200 h at 500 atm. The viability of the naturally occurring fecal coliforms in sewage exposed to moderate pressures at 4 C was found to be similar to the survival patterns demonstrated with pure cultures of E. coli. The total numbers of aerobic bacteria in these sewage samples, however, stabilized at 500 and 1,000 atm after 100 h, and at 1 and 250 atm there was significant growth of sewage-associated bacteria, which apparently utilized the organic compounds in the seawater-diluted sewage samples. A preliminary classification of some of these bacteria indicated that approximately 90% (160 isolates) of the organisms that survived over a 400-h exposure to 500 and 1,000 atm were Arthrobacter/Corynebacterium species, and the representative organisms capable of growing at 1 and 250 atm in seawater at 4 C were gram-positive cellulose digesters and an unidentified gram-negative coccus. The significance of these results with respect to the contamination of the deep ocean with human pathogens and the possibility of sewage-associated microorganisms growing and competing with indigenous marine microbial flora in situ is discussed.

Arthrobacter↗

PubMed1975

Prevention of sewage pollution by stabilization ponds.

Water is polluted when it constitutes a health hazard or when its usefulness is impaired. The major sources of water pollution are municipal, manufacturing, mining, steam, electric power, cooling and agricultural. Municipal or sewage pollution forms a greater part of the man's activity and it is the immediate need of even smaller communities of today to combat sewage pollution. It is needless to stress that if an economic balance of the many varied services which a stream or a body of water is called upon to render is balanced and taken into consideration one could think of ending up in a wise management programme. In order to eliminate the existing water pollutional levels of the natural water one has to think of preventive and treatment methods. Of the various conventional and non-conventional methods of sewage treatment known today, in India, where the economic problems are complex, the waste stabilization ponds have become popular over the last two decades to let Public Health Engineers use them with confidence as a simple and reliable means of treatment of sewage and certain industrial wastes, at a fraction of the cost of conventional waste treatment plants used hitherto. A waste stabilization pond makes use of natural purification processes involved in an ecosystem through the regulating of such processes. The term "waste stabilization pond" in its simplest form is applied to a body of water, artificial or natural, employed with the intention of retaining sewage or organic waste waters until the wastes are rendered stable and inoffensive for discharge into receiving waters or on land, through physical, chemical and biological processes commonly referred to as "self-purification" and involving the symbiotic action of algae and bacteria under the influence of sunlight and air. Organic matter contained in the waste is stabilized and converted in the pond into more stable matter in the form of algal cells which find their way into the effluent and hence the term "stabilization pond".

India↗

PubMed1977

Persistence of poliovirus 1 in soil and on vegetables grown in soil previously flooded with inoculated sewage sludge or effluent.

Land disposal of sewage sludge and effluent is becoming a common practice in the United States. The fertilizer content and humus value of such wastes are useful for agricultural purposes, and the recycling of sewage onto the land eliminates many of our stream pollution problems. The potential exists for crops grown in such irrigated soil to be contaminated by viruses that may be present in the sewage. Studies were initiated to determine viral persistence in soil and on crops grown under natural conditions in field plots that had been flooded to a depth of 1 inch (2.54 cm) with poliovirus 1-inoculated sewage wastes. Lettuce and radishes were planted in sludge- or effluent-flooded soil. In one study, the vegetables were planted 1 day before flooding, and in another they were planted 3 days after the plots were flooded. Survival of poliovirus 1 in soil irrigated with inoculated sewage sludge and effluent was determined during two summer growing seasons and one winter period. The longest period of survival was during the winter, when virus was detected after 96 days. During the summer, the longest survival period was 11 days. Poliovirus 1 was recovered from the mature vegetables 23 days after flooding of the plots had ceased. Lettuce and radishes are usually harvested 3 to 4 weeks after planting.

Poliovirus↗

PubMed1977

Persistence of enteroviruses in sewage sludge.

Sewage from residential areas often contains viruses pathogenic for man and significant amounts are probably associated with solids in sewage sludge. Information on the survival of viruses in sewage sludge is necessary in order to develop guidelines for recycling programmes that involve spreading the sludge on land. In the present study, a number of enteroviruses were added to sewage sludge and the artificially contaminated sludges were tested for viruses at intervals over a 12-week period. Most of the viruses survived for many weeks at room temperature. It is clear that sewage sludge destined for land application should be adequately treated for virus inactivation. In interpreting these results, it should be borne in mind that the survival of hepatitis A virus might be similar. Recent reports about the reappearance of poliomyelitis in regions with immunization programmes should also be taken into consideration.

Enterovirus↗

PubMed1978

[Network for the epidemiological survey of the enteroviruses in sewage (author's transl)].

Poliomyelitis still occurs each year in France: 27 cases in 1973, 21 cases in each of 1974 and 1975, 8 cases in 1976. Because of the risk, a survey of the spread of poliovirus in healthy populations and in sewage was organized by the Ministry of Health according to the departmental note DGS/HP/1st/250, 9-2-73. The Laboratoire d'Epidémiologie Virale of the Laboratoire National de la Santé was in charge of the technical aspects of the survey. A preliminary questionnaire was sent to each D.D.A.S.S. (Direction Départementale de l'Action Sanitaire et Sociale) in order to find out the local possibilities for sampling and preliminary treatment of the sewage samples. In 1974, all the samples were sent to the Laboratoire d'Epidémiologie Virale. Since 1975, samples have been sent to a local virology laboratory when available. The sewage samples were concentrated according to SHUVAL's or LUND's methods depending on the local conditions. Both methods tested in our laboratory were found equally efficient. In order to improve their technical laboratory methods, the virologists collaborating in this survey joined together in a working group "Virus et Eaux". For isolating the enteroviruses, we recommend the inoculation of each concentrated sample into primary monkey kidney cells grown in vials; an overlay of agar is added after inoculation. This plaque method allowed us to isolate several strains from one sample. It was possible to demonstrate that polioviruses differing in serotypes and thermosensitivity might be detectable in the same sample. Few of the isolated polioviruses (11/272) showed the same thermoresistance as did the wild strains. Certain enterovirus serotypes are known to be responsible for epidemics of meningitis and neurological disorders. It was of interest to identify non-poliomyelitic enteroviruses isolated from sewage. The study of enterovirus spread in sewage in comparison with that in healthy children is in progress.

Animals↗

PubMed2026

Microfiltration (MF) and Ultrafiltration (UF) for Sewage and Surface Water Concentration for SARS-CoV-2 and Other Enveloped Viruses' Detection in Wastewater-Based Epidemiology (WBE).

This study objective was to evaluate hollow fiber membranes for concentration of enveloped enteric viruses in sewage and surface water samples. Microfiltration (MF, 0.2 µm nominal pore size) and ultrafiltration (UF, 100 kDa molecular weight cut-off) hollow fiber membranes were compared for the concentration of the bovine respiratory syncytial virus, and the influence of initial sample volumes (1, 1.5, and 2 L), permeate recovery rates (60%, 70% and 80% of the initial volume collected as permeate, equivalent to volumetric concentration factors of 2.5, 3.3 and 5), and backwashing was assessed. Polyethylene glycol precipitation followed by centrifugation (PEG-C) was evaluated both as a stand-alone method and as a secondary step applied to the membrane concentrate. MF and UF membranes had a similar capacity to retain pollutants and to concentrate organic matter in most parameters and conditions (p > 0.05). In sewage, increasing the initial volume from 1 to 2 L raised recovery from 20.7 ± 0.1% to 30.0 ± 0.1% with MF and from 20.8 ± 0.1% to 25.3 ± 0.1% with UF (p < 0.05), whereas changes in the permeate recovery rate produced no significant differences (p > 0.05). In surface water recovery did not exceed 5.5%, and every increment in the permeate recovery rate produced a significant increase (p < 0.05). Backwashing had a stronger effect on RNA recovery than pore size or the remaining operational parameters, reaching 29.3 ± 9.3% with MF and 33.8 ± 13.7% with UF in sewage and nearly doubling recovery in surface water. In sewage, PEG-C alone (14.1%) was statistically similar to membrane filtration alone (12.1% to 12.3%, p > 0.05), while combining both techniques raised recovery to 23.0% to 25.5%. In surface water, membranes alone recovered 0.8% against 2.4% for PEG-C (p < 0.05), and the combination of UF with PEG-C reached 5.7%, making it a valid alternative, albeit more time consuming and requiring additional equipment. Recoveries are expressed as the ratio between the genome copy concentration in the concentrate and in the spiked sample; on a total genome copy basis they correspond to 4% to 9% in sewage and to about 1% in surface water.

tangential filtration↗

PubMed1979

Sewage sludge as a source of cadmium in soil-plant-animal systems.

The objective of this presentation is to relate the abundance and mobility of Cd in components of terrestrial ecosystems with implications for land utilization of sewage sludge. The uptake of Cd by crop plants is a function of the quantity of the element in the soil plus other soil factors affecting the Cd ion activity or electrochemical potential at the plant root surface. The natural abundance of Cd in soils has been reported as 0.5 mug/g which is higher than the background level of 0.2 mug/g found in soils studied in Pennsylvania. Experimental results indicate that the plant availability of Cd increases with each soil addition. While the plant availability of Cd is decreased by liming to increase soil pH, it has not been possible to add Cd salts or sewage sludge Cd without significantly increasing plant uptake. Field studies have shown that land application of sewage sludge can be expected to increase the Cd concentration of corn leaves from a range of 0.05-0.1 mug/g to 1-3 mug/g. Two years after the last application of sludge which added up to 10 ppm Cd to the surface soil, corn grain, sorghum grain, wheat grain, and potatoes showed a 10- to 15-fold increase in Cd over background levels. Studies were conducted with chicks, laying hens, and meadow voles (Microtus Pennsylvanias) to assess the impact of this increase in plant Cd upon the food chain. Corn and sorghum plants were grown on soils with either inorganic or sludge fertilizer for the purpose of producing herbage for use in feeding trials with meadow voles. Eight diets and a synthetic control diet were formulated to study the effect of source (plant vs. inorganic) of Cd on tissue accumulation. Significant accumulation of Cd occurred in kidney and liver, but not muscle, of voles fed diets containing sludge fertilized corn (1.09 mug/g) or sludge fertilized sorghum (2.76 mug/g). The source of Cd had little influence on tissue accumulation. In studies with broiler chicks and laying hens, natural diets containing 0.2 ppm Cd were supplemented with 3 ppm of this element. As with the meadow voles, Cd readily accumulated in liver and kidney. Although the results were not statistically significant, 3 ppm dietary Cd doubled muscle Cd content. There was no transfer of Cd to egg in a long term (12 month) experiment with laying hens. Soil management programs have been developed to maintain animal dietary levels of Cd at less than 1.0 mug/g from the use of sewage sludge on land in Pennsylvania. However, it is concluded that this level over time may cause a significant accumulation of Cd in animal tissues. Interpretation of these results in relation to those for human intake of Cd and the long range health effects of Cd is required for the proper monitoring of sewage sludge applications on land used for production of crops which enter the food chain.

Animals↗

PubMed1976

[Long-term survival of E1 Tor cholera vibrios in naturally contaminated sewage].

El Tor cholera vibrios of Ogava serological type were revealed in the sewage of the locomotive shed for 15 months. In experiment with an oil catcher in naturally infected sewage El Tor vibrios survived 36 days, in storage of this sewage at the laboratory--39 days, in the artificially infected sewage of a settlement and of a milk plant--2 and 11 days, respectively, in the oil and disel fuel--14 months. Consequently, El Tor vibrio can survive in the sewage with a high oil product content for a long time.

Time Factors↗

PubMed1976

Mycoflora of activated sewage sludge.

Thirty-eight species of fungi were identified in pure culture after isolation from activated sewage sludge by serial dilution. Nine species and genera were identified that had not been previously reported. In 1963, Cooke (1) published an excellent laboratory guide on the identification of fungi from polluted water, sewage, and sewage treatment systems; of approximately 30 papers cited only one (2) dealt with fungi from activated sewage sludge. Later (1970), Cooke & Pipes (3) enumerated 47 fungi consisting of 4 genera of yeasts and 33 genera of filamentous fungi that had been isolated from activated sludge. This paper reports the mycoflora of anaerobically digested sludge from a residential area in Auburn, Alabama.

Alabama↗

PubMed1975

Absence of hepatitis B antigens from feces and sewage as a result of enzymatic destruction.

Hepatitis B surface antigen (HBs Ag) was not detected in sewage by means of a sensitive affinity chromatography method combined with radioimmunoassay. The antigen was also absent from the feces and urine of 23 patients with HBs Ag antigenemia; this observation indicates that HBs Ag is rarely discharged into sewage. The absence of HBs Ag from feces is ascribed to antagonists of an enzymatic nature or to carboxypeptidase A, which destroys the antigen. Antagonists with similar effects were produced by three species of Pseudomonas but were not produced by various other bacteria. HBs Ag was also destroyed by two subtilisin enzymes. When hepatitis B sera were incubated with these enzymes or with the antagonists, small spherical particles, tubules, and the coats of Dane particles disappeared first, and Dane cores disappeared later. Although sewage or activated sludge did not affect the stability of HBs Ag, the results indicate that even Dane cores are not excreted in feces and that sewage plays a negligible role in the spread of HBs Ag, Dane cores, and viral hepatitis type B.

Bacteriological Techniques↗

PubMed1977

Destruction of coliforms in water and sewage water by dye-sensitized photooxidation.

A new approach to disinfection of water and sewage water, by oxidative destruction of microorganisms by photosensitization, is described. Samples of water and sewage water, to which an inoculum of fecal Escherichia coli had been added, were exposed to solar radiation in the presence of a dye sensitizer, under continuous aeration. The effects of the sensitizer methylene blue at concentrations of 0 to 10 mg/liter, different radiation times from 0 to 2 h, and sunlight intensities of 0, 68, and 2,030 muE/m2 per s were investigated. In laboratory-scale experiments, 1.3 X 10(9) coliforms in 100 ml of oxidation pond municipal sewage water containing 0.5 mg of methylene blue were destroyed in about 30 min. Similar results were obtained with nonchlorinated potable water. These results demonstrate the possibilities available for the disinfection of water and sewage water by this method.

Air↗