Showing 7 results for Coliform
M.h Dehghani, M Ghaderpoori, M Fazlzadeh, S Golmohamadi,
Volume 2, Issue 2 (9-2009)
Abstract
Backgrounds and Objectives:Safe drinking water providing is one of the main purposes in the community. Development and improvement of community is related to the public health. In this study !we studied the bacteriological quality of 116 villages under coverage of the water and wastewater companies in rural areas of Saqqez in.1386
Material and Methods:Drinking water of these rural areas have provided of deep, semi-depth- wells and spring water sources. Because in numerous rural areas both sources of drinking water and in some of them different sources of drinking water were used (old and new storage water source), in general, 359 samples were collected and transferred to the laboratory for testing to evaluate its quality. We also used linear Regression statistical analysis for collected data.
Results:results show that residual chlorine in drinking water in 33.88 percent of rural areas population were in range 0.2-1 mg/l. For 98.3 percent of the seqqez rural population, the turbidity was lower than the maximum permissible levels of drinking water standards of Iran (5 NTU). There was no any E.coli contamination in 88 percent of drinking water in saqqez rural areas.
Conclusion:Based on WHO guidelines concerning the microbial quality of water published in 2006! the average indicator for lack of E.coli in water of rural areas of seqqez was 88 percent and water is safe or good for drinking.
P Atabakhsh, M.m Amin, H Mortazavi, M Yaran, A Akhavan Sepahi, A Nouhi, M Jalali,
Volume 3, Issue 3 (10-2010)
Abstract
Backgrounds and Objectives:Total and Fecal coliforms (TC and FC), heterotrophic plate count (HPC), were counted by microbiological method and E.coli O157:H7 were detected through immunological and Real time PCRmethods inwater intake and all of units of Isfahanwater treatment plant (IWTP).
Materials and Methods: The microbial profile including TC, FC, and HPC, were monitored and turbidity and total organic carbon were analyzed in 8 locations of water intake, and unit operation and processes of IWTP, including, inlet, sedimentation, ozonation, and filtration and finished water. Immunological method through anti-serum kits and molecular method of RT-PCR were used to detect E.coli O157:H7 in the 8 locations and also the sludge of the sedimentation basin and filters backwash water of IWTP.
Results: Survival of E.coli O157:H7 in sludge sample of sedimentation basin was indicated by formation of agglutination particles in immunological method and through indicator probes in the RT-PCR method. However, E.coli O157:H7 was not detected in water samples of other units of IWTP. The removal percent of TC, FC, and HPC were: 59.5, 49, and 54.8 % in sedimentation basin 66, 45.8, and 57 % in ozonation: 98.8, 98, and 78.8 in the filtration and 96, 100, 91% in disinfection, respectively.
Conclusion: This study approved the existence of the pathogenic coliform, E.coli O157:H7 in the
sludge of sedimentation basin. Absent of E.coli O157:H7 in the finished water indicates that the existing units of IWTP could eliminate these pathogenic bacteria, before reaching the final units of the plant, including the filters and disinfection.
A Mirzaei, A Takdastan, N Alavi Bakhtiarvand,
Volume 4, Issue 3 (10-2011)
Abstract
Backgrounds and Objectives: Selection of proper coagulants for turbidity removal and determination of effective methods to reduce coagulants dose and related costs in water treatment plants is of critical importance. The present study investigates the effect of returned sludge on improving the performance of poly-aluminum chloride (PAC) in turbidity, coliform bacteria, heterotrophic bacteria removal from drinking water during rapid mixing phase.
Materials and Methods: In order to determine the optimal returned sludge volume injected during rapid mixing with PAC for turbidity, total coliform and hetrophic bacteria, experiments were conducted based on variables such as injected silt volume (from 0 - 125 ml), and varying turbidities from 58 - 112 NTU. At the end of each JAR experiments, remaining turbidity , microbial parameters of samples were measured . Coagulant efficiency in turbidity removal and microbial parameters were determined by Covariance, Duncan analyses and graphs were drawn by MS Excel . The results statistically showed significant among variables (P<0.05).
Results: The results showed that the maximum turbidity removal efficiency of 98.92 at 30 ppm was 10 ml while the maximum turbidity removal efficiency of 98.31 at 10 ppm was 4 ml. The maximum total coliform removal efficiency of 95.68 obtained for 10 ppm in 10 cc injected sludge volume.
Conclusion: This study shows that addition of returned sludge to flash mixing can reduce the turbidity of samples.
Afsaneh Alinezhadian, Ahmad Karimi, Jahangard Mohammadi, Farzaneh Nikookhah, Mathias Niuman. Anderson,
Volume 6, Issue 3 (12-2013)
Abstract
Background and Objectives: In arid and semi-arid regions, wastewater reuse has become an important element in agriculture. However, irrigation with this resource can be either beneficial or harmful, depending on the wastewater characteristics. The aim of this research was to investigate the soil bacterial and crops quality irrigated with treated wastewater.
Material and Methods: This research was conducted on a maize field near the wastewater treatment plant in Shahr-e-kord in summer,2011. Plots were arranged in a randomized complete block design in 3 replications and 2 treatments, well water (W1) with fertilizer and effluent (W2).
Results: At the end of growth season, soil samples were collected from depth of 0-5 and 5-15 cm and plant samples consisting of old and new leaves and seeds were collected for bacteriological analysis. According to bacteriological analysis, total number of positive lactose bacteria, total and fecal coliforms in depth of 0-5 cm was 42% more than depth of 5-15 cm. In the case of old leaves, total number of coliform and fecal coliform was 88 and 40 MPN/100 mL respectively. Moreover, for new leaves, it was 38 and 2 MPN/100 ml respectively.
Conclusion: According the results, number of indicator bacteria in soil is decreased (about 35%) by passing time.
B Ghoreishi, M Shaker Khatibi, H Aslani, A Dolatkhah, A Abdoli Seilabi, M Mosaferi,
Volume 9, Issue 1 (6-2016)
Abstract
Background and Objectives: Qualitative evaluation of sewage sludge before any kind of application is essential. The present study was aimed to investigate Total coliform, Fecal coliform and Salmonella in sewage sludge produced at wastewater treatment plants in Azerbaijan Province, Iran.
Materials and Methods: Nine wastewater treatment plants were chosen in East Azerbaijan Province, and their sludge from drying bed was studied. Total coliforms, thermo-tolerant coliforms, and Salmonella spp., were surveyed during winter time, 2015. Total and thermos-tolerant coliforms were enumerated by EPA method 1680 and salmonella was counted using EPA method 1682.
Results: In the case of total coliform, sludge sample from Jolfa with 1.82×106 MPN/g showed the highest contamination, while Sarab showed lowest fecal coliform count with 2.02×103 MPN/g. As in the case for fecal coliform, the bacteria count for thermo-tolerant coliforms was higher in Jolfa than other cities; on the other hand, Ahar with no fecal coliform count or less than 2.2 showed the minimum contamination rate to fecal coliforms. In case of Salmonella spp., sludge samples from Ahar and Bostan Abad did not show any salmonella. While sludge sample from Tabriz wastewater treatment plant was determined as the most contaminant sludge with bacteria count equal to 84 per g. Moreover, sludge sample from Sarab wastewater treatment plant showed the least contamination rate, and bacteria count was 6 per g.
Conclusion: From the stand point of microbial quality, all sludge samples met class B standards set by USEPA, while none of them could provide class A standards. Thus, special precautions must be taken in case of soil amendments by the sludge produced from wastewater treatment plants.
A Beiki, M Yunesian, R Nabizadeh, R Saeedi, L Sori, M Abtahi,
Volume 9, Issue 1 (6-2016)
Abstract
Background and objectives: Swimming is one of the most popular sport fields and entertainments that has considerable benefits for human health, but on the other hand microbial water contamination in swimming pools through transmission and spread of infectious diseases is a significant threat against public health. In this study, microbial water quality of all public swimming pools in Tehran were assessed and effective factors on microbial water quality were analyzed.
Materials and Methods: This cross-sectional study with the analytical approach was performed in 2013. The whole public swimming pools in Tehran were inspected and water samples were taken for measurement of microbial indicators including thermotolerant coliforms, heterotrophic plate count (HPC), and physicochemical parameters affecting the microbial water quality including turbidity, free residual chlorine and pH and an integrated swimming pool microbial water quality index were used to describe the overall situation. Operational parameters with probable effects on microbial water quality were checked through inspection using a checklist.
Results: The assessment of the swimming pool microbial water quality indicated that the compliance rates of thermotolerant coliforms and HPC were 91.4 and 84.5%, respectively. Compliance rates of free residual chlorine, turbidity, Ph, and temperature were also obtained to be 82.7, 45.5, 85.6, and 65.4% respectively. Based on the integrated swimming pool microbial water quality index, the proportions of swimming pools with excellent and good microbial water quality were 39.6 and 50.4% respectively and the others had not proper microbial water quality. The parameters of water free residual chlorine and turbidity, swimmer density, water recirculation period, dilution amount, cleaning, usage rates of shower and disinfection basin and operation of water treatment systems had significant effects on the microbial indicators (P<0.05).
Conclusion: The study showed that the overall microbial water quality status of public swimming pools in Tehran was acceptable and analysis of the results determined the most efficient interventions for improvement of the microbial water quality of the pools.
Reza Kheiri Soltan Ahmadi, Habib Nazarnejad, Farrokh Asadzadeh,
Volume 14, Issue 4 (3-2022)
Abstract
Background and Objective: With the industrialization of communities, population increase and use of surface water, river pollution has been increased by agricultural, industrial pollutants and urban wastewater. Therefore, investigation of river pollution for regional and environmental planning is of great importance. To evaluate surface water pollution, a number of surface water quality indices have been investigated.
Materials and Methods: Iran water quality index for surface water resources (IRWQISC) approach was used to evaluate the water quality of the Mahabadchai river, Iran. Sampling was carried out along the Mahabadchai river based on some criteria such as approximately to drainage areas for landfills/domestic and agricultural effluents.
Results: Pearson correlation coefficient between physical, chemical and microbial parameters of water showed that fecal coliform, BOD, COD, nitrate, ammonium, phosphate, turbidity and total hardness had a significant positive relationship with each other at 99% confidence. According to this index, upstream samples of the river are classified as good, mid-stations relatively good to moderate category, and downstream samples of the river are classified as relatively bad.
Conclusion: Based on the relationship between each variable, fecal coliform, BOD, COD, ammonium, and turbidity were more effective in determining the IRWQISC. Most of the examined variables showed low concentrations in upstream areas of the river while their concentration gradually increased along the river to downstream areas, especially close to urban and industrial districts.
