• Journal of Korean Society on Water Environment
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• v.22 no.1
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• pp.166-171
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• 2006

The objectives of the present paper were to investigate the concentration of total coliform in wastewater effluents and the effect of water chemical and physical characters in it. The most correlated parameter with total coliform was COD. It means that the wastewater treatment efficient effects on total coliform concentration. And we developed predictive model for the total coliform concentration. The estimated parameters for model were COD, temperature, nitrite, chloride, Mn and regression model equation was determined; log (Total Coli.) = 1.861+0.065[COD]+0.038[temperature]-0.0004[$Cl^-$]+3.697[Mn]-0.32 [$NO_2-N$] The developed model provided very strong correlation ($R^2:0.82$) between total coliform and regression equation. The parameters having high sensitivity were COD and temperature. So the study indicated that if the temperature and COD of wastewater effluent were known, we would estimate the concentration of total coliform and decide the most effective usage of chlorine.

• Journal of Environmental Health Sciences
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• v.32 no.3
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• pp.215-221
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• 2006

This study investigated the inactivation of the total coliform, an indicator organism in chlorine dioxide, in order to assess the optimal disinfection procedure for drinking water treatment and distribution systems. This research focus on a number of factors, including the dosage of disinfectant, contact time, pH, temperature and DOC. Water samples were taken from the outlet of a settling basin at a conventional surface water treatment system. As the pH increased in the range of pH 6-9, the bactericidal effects of disinfectants decreased. Changes in levels of pH did not significantly after the disinfection effect of chlorine dioxide for total coliform. With an increase in temperature, there was a subsequent increase in the bactericidal effects of disinfectants. Thus, it is evident that a decrease in temperature will higher the CT values required to inactivate coliform for during the winter. DOC addition can also reduce total coliform inactivation. DOC is the most significant variable in total coliform inactivation with chlorine dioxide.

• Journal of Korean Society on Water Environment
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• v.21 no.5
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• pp.516-519
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• 2005

An useful protocol coiled load duration curve methodology to estimate contaminant loading to a river on an exceedance probability scale was developed in this research. The technique was further applied to estimate total coliform loading to the Geum River, using the daily mean flow rate and total coliform concentration data during January, 1996 and July, 2004 for the Gongju where an automated monitoring station is located. Drought flow of the Gongju (=50.3 cms) was equivalent to 40% on an exceedance probability scale. Load duration curve for total coliform loading at the Gongju was constructed. Standard duration curve was constructed with the water quality criteria for the class 2 (total coliform concentration = 1000 MPN/100 mL). By plotting load duration curve with standard duration curve, it could be revealed that water quality do not meet the desired water quality for 47% on an exceedance probability scale. If linearity between flow rate and coliform concentration is assumed, it can be interpretated that water quality exceeds desired criteria when average mean flow rate is over 51 cms.

• Journal of Korean Society of Rural Planning
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• v.12 no.2 s.31
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• pp.57-64
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• 2006

The experiment was carried out to determine the distribution of total coliform the translocation of heavy metals and the salt accumulation in soils following the supply of ground water, the domestic wastewater and the ultraviolet treatment of domestic wastewater during the spinach and the chinese cabbage cultivation. There were not much changes in the Total-N, Total-P and cations in soils following the ultraviolet treatment of the domestic wastewater. However, the density of total coliform was dramatically reduced from 894MPN/100mL to 5MPN/100mL. The diagnosis of composition of soil after the harvest of chinese cabbages and spinach has shown that the concentration of Na$^+$ was 3-4 times higher in plot using domestic wastewater than in plot using ground water. When domestic wastewater and ground water were used in growing spinach md chinese cabbage at 50% each, the application of chemical fertilizers reduced about 25% to 50% compared to the criteria set down by the Rural Development Administration and there was not significant difference in terms of harvest. Using non-ultraviolet treatment of domestic wastewater directly on spinach and chinese cabbage has resulted in excessive density of total coliform at 25,000MPN/100mL. Even when ultraviolet treatment, the density was still high at 2,000MPN/100mL. The high density of total coliform even following ultraviolet treatment of domestic wastewater is considered to be caused by photo-reactivation of micro-organism. When reusing domestic wastewater, the application of sterilization such as ultraviolet, ultrasonic and electron-beam for public health and hygiene reasons may provide safe supply of agricultural water.

• Proceedings of the Korean Environmental Health Society Conference
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• 2003.06a
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• pp.140-143
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• 2003

This research was to determine and compare the inactivation of total coliform as the indicator organism with chlorine, chlorine dioxide and ozone for drinking water treatment. The inactivation of total coliform was experimentally analyzed for the dose of disinfectant, contact time, pH, Temperature and DOC. The experiments for the characterization of inactivation were performed in a series of batch processes with the total coliform as a general indicator organism based on chlorine, chlorine dioxide and ozone as disinfectants. The nearly 2.4, 3.0, 3.9 log inactivation of total coliform killed by injecting 1mg/L at 5 minutes for chlorine, chlorine dioxide and ozone. For the inactivation of 99.9%, Disinfectants required were 1.70, 1.00 and 0.60 mg/L for chlorine, chlorine dioxide and ozone, respectively. The bactericidal effects of disinfectants were decreased as the pH increased in the range of pH 6-9. The influence of pH change on the killing effect of chlorine dioxide was not strong, but that on ozone and free chlorine was sensitive. The bactericidal effects of the disinfectants were increased as the temperature increase. The activation energies were 36,053, 29,822, 24,906 J/mol of chlorine, chlorine dioxide, ozone for coliforms. The inactivation effects were shown in the lowest order of chlorine, chlorine dioxide and ozone.

• Journal of Environmental Health Sciences
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• v.12 no.2
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• pp.39-48
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• 1986

This study was carried out to investigate the bacterial contamination of Ice Tea sold on the l street in Seoul area. For this, study 81 samples were collected on the street from July to September, 1985 and were examined on the following items. 1. Degree of bacterial contamination. 2. The relation of the occurrence of fecal coliform and salmonella. 3. The change of bacterial contamination in Ice Tea against temperature. As the results of this study, the following conclusion were obtained. 1. The mean count of total viable bacteria by standard plate count was $6.5{\times}10^3$/ml, the mean count of total coliform and fecal coliform by MPN method were $3.4{\times}10^2$/100ml, 5.5/100ml and those of fecal streptococci was $3.2{\times}10^2$/100ml. 2. The mean count of Staphylococcus aureus was 10.5/ml, the isolated rate of salmonella was 7.41%. 3. In relation to the occurrence of fecal colfform and salmonella, salmonella isolated that for values above $10^2$ fecal coliform 100ml. 4. In the change of bacterial contamination in Ice Tea against temperature, the number of total coliform and fecal coliform increased at $25{\circ}$C, decreased at $4{\circ}$C, but fecal streptococci increased at $25{\circ}$C and $4{\circ}$C.

• Journal of Food Hygiene and Safety
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• v.31 no.3
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• pp.222-225
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• 2016

In this study, the performance of five selective media for coliform bacteria was evaluated. In total, 83 coliform isolates from ready-to-eat food and 21 reference strains were inoculated in five agar media : Chromocult coliform agar (Merck Millipore), HiCrome coliform agar (Sigma), CHROMagar ECC chromogenic media, Brilliance E. coli/coliform selective agar (OXOID), and endo agar (Merck Millipore). Coliform isolates and reference strains were inoculated on the selective media to test media sensitivity and specificity. The tested media showed the following sensitivities for the isolated strains: Chromocult coliforms agar and HiCrome coliform agar, 94%; Brilliance E. coli/coliform selective agar, 93%; CHROMagar ECC chromogenic media, 92%; and endo agar, 74%. In addition, all media showed 100% specificity, except for endo agar (71%). Moreover Chromocult coliform agar and HICrome coliform agar showed high levels recovery. Taken together, these results identified Chromocult coliform agar and HICrome coliform agar as an effective selective medium for coliforms with higher sensitivity and specificity compared to other media tested in this study.

• Journal of Environmental Health Sciences
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• v.19 no.2
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• pp.34-39
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• 1993

One hundred and eighty-seven water samples were collected from 23 of spring water, 2 of ground water, 1 of tap water in Pusan area and 3 of natural mineral waters. Total coliform group, fecal coliform, viable cell count and microflora were investigated to evaluate water quality of drinking water. The results were as follows: range and geometric mean value of total coliform and fecal coliform MPN's of spring water were 0~1,500/100 ml, 85/100 ml and 0~460/100 ml, 24/100 ml but coliform group was not detected in the samples of tap water and natural mineral water. Viable cell count of spring water, ground water and tap water were lower as 100 cell than the criteria for drinking water but that of natural mineral water was higher as 6.5X 10$^2$~7.4X 10$^3$ /ml. Predominant speces among the 219 strains isolated from the samples were 19.6% Aeromonas spp., 19.2% Enterobacteriaceae, 16% Acinetobacter spp. Especially, spring water and vessels were contaminated by Hafnia spp. and Providencia Spp, inhabitant of the oral cavity.

• Journal of Environmental Health Sciences
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• v.9 no.2
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• pp.1-10
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• 1983

The purpose of this study was to analyze general ingredient of bean cured on the market and to examine its exposure to bacterial contamination. For this study, 17 samples (each 9 samples for general bean curd, soft bean curd, and uncurdled bean curd) were randomly collected from nine areas in Seoul from the beginning of April, 1983 to the beginning of June, 1983. The result of ingredient analysis of moisture, ash, and protein of bean curd was compared with the standard set by the Ministry of Health & Social Affairs. In order to find out exposure of bean curd on the market to bacterial contamination, total biological bacteria and coliform group were examined. Experimental results were shown as follows 1) Results of ingredient analysis of moisture, ash, and protein of general bean curd showed that total samples in both moisture and protein met the standard set by the Ministry of Health & Social Affairs but 44.4% of the samples in ash was below the above standard, indicating average 82.0%, 0.9% and 9.6% in moisture, ash, and protein order. 2) Experimental results of moisture, ash, and protein of soft bean curd demonstrated 90.2%, 0.5% and 4.3% respectively total samples in both moisture and protein satisfied the self-criteria set by the Soft Food Co-operative Association of Seoul City but 11.1% of the samples in ash didn't meet the self-criteria. 3) Total samples of uncurdled bean curd satisfied the self-criteria set by the above association, indicating average 92.0%, 0.4%, and 3.5% in moisture, ash, and protein order. 4) Total biological bacteria and coliform group detected in general bean curd showed that more than 10$^5$/g in total biological bacteria accounted for 88.8% of the samples and that 10$^4$/g or more in coliform group accounted for 77.7% of the samples. The result proves that general bean curd has been exposured to a severe bacterial contamination. 5) Result of total biological bacteria and coliform group detected in such packed bean curd as uncurdled bean curd and soft bean curd showed that 61.6% of the samples exceeded 10$^6$/g in total biological bacteria and 27.7% of the samples exceeded 10$^3$/g in coliform group. 6) According to the change with time and temperatures in total biological bacteria and coliform group of general bean curd, general bean curd began to decay around 72 hours at 4$\circ$C and around 48 hours at 23$\circ$C and around 24 hours at 37$\circ$C and, at that time, total biological bacteria approached 10$^6$/g while coliform group did 10$^6$/g. The result indicates that temperature has a great effect on bacteria counts and decay.

• Journal of The Korean Society of Agricultural Engineers
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• v.55 no.3
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• pp.105-111
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• 2013

Probability distribution of microbes in wastewater is a crucial factor to be determined for microbial risk assessment associated with its reuse. The objective of this study was to investigate probability distribution of an indicator microorganism in wastewater. Daily total coliform counts measured from nationwide wastewater treatment plants in 2010 by the Ministry of Environment were used for statistical analysis. Basic statistics and probability distributions were estimated in the three different spatial scales using the MS Excel software and FARD2006 model. Overall, wastewater from manure and livestock treatment plants demonstrated greater median coliform counts than from sewage and village treatment plants. Generalized logistic (GLO) and 2-parameter Weibull (WBU2) appeared to be the two probability distributions that fitted best for total coliform numbers in wastewater. The study results of microbial statistics and probability distributions would provide useful data for quantitative assessment of microbial risk from agricultural wastewater reuse.