• Parasites, Hosts and Diseases
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• v.43 no.2 s.134
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• pp.47-50
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• 2005

A survey was carried out from August to December 2004 in Pusan, Korea to document the presence of free-living amoeba (FLA), including the genus Acanthamoeba, in both contact lens storage cases and domestic tap water. Acanthamoeba was isolated from $5(4.2\%)$ in 120 contact lens storage cases. Four house tap water samples from residents, whose contact lens storage cases had been contaminated by Acanthamoeba, were also found to be contaminated with Acanthamoeba. Therefore, the contamination rate of FLA and Acanthamoeba in domestic tap water was investigated in order to examine the role of domestic tap water in Acanthamoeba contamination of contact lens storage cases. FLA and Acanthamoeba were identified in $97(46.8\%)\;and\;16(7.7\%)$ of the 207 domestic tap water samples, respectively. There were no significant differences between the contamination rates of FLA in tap water according to the filtration plant of origin. No FLA was detected in the tap water directly supplied by the water purification plants. Water storage tanks appear to promote FLA colonization, including Acanthamoeba, in domestic tap water. This increases the risk of Acanthamoeba contamination in contact lens storage cases as well as increasing the risk of Acanthamoeba keratitis.

• Journal of Korean Society of Water and Wastewater
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• v.23 no.6
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• pp.753-761
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• 2009

Bottled water market is growing at a rate of 10% per year in Korea. However, bottled water exhausts ground water. Korean government proposed to provide 'bottled tap water' at a low price in 2008. This study is the estimation of 'bottled tap water' market scale using binary logit model. we calculate that 'bottled tap water' market scale is from at least 92 billion won to 154 billion won by 150, 250 won per a bottled water, respectively. This paper indicates that scale of 'bottled tap water' market is a half of 'bottled water' market in 2007. This result provides that policy-makers with available and responsible information regarding the scale of 'bottled tap water' market.

• Journal of Korean Society of Water and Wastewater
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• v.28 no.4
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• pp.461-472
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• 2014

The tap water plays a critical role in our daily life by providing clean water for drinking as well as for residential use. Its importance, however, is often hidden and criticized in mass media because drinking the unprocessed tap water as a primary source of drinking water is very low comparing to other countries. This is because survey tool in Korea is often different from those in other countries so their results on the tap water cannot be directly compared without analysis on survey questionnaire. Therefore, we examplified cases showing the difference of questions of each country and discussed the reason why results of tap water intake should not be compared without analysis on the questions. Also, distrust on Arisu without rational reason is known as the first reason of distrust on the tap water. However, it was not the ultimate reason of distrust on the tap water. To verify, we designed survey questions in a tricky way that the same question was asked twice with different choices in the survey questionnaire. Most of the people who distrust Arisu without rational reason at the first question were selected different choices and significantly reduced in the second question. This proved that the ratio of distrust on the tap water is not actually the right reason and that by providing more choices, people's distrust on the tap water without rational reason can turn into more specific reasons.

• Hwankyungkyoyuk
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• v.24 no.4
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• pp.78-93
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• 2011

Clean and safe water is the fundamental element for the good life of people. However, expanding the distrust on the tap water increased the anxiety on drinking water and accelerated the growth of the natural and purified water market. In this respect, this study was made to find an opportunity to invigorate the use of the Seoul tap water for drinking by means of assessing the awareness of the citizen and the current condition on the tap water in Seoul. The findings were that the direct use of the tap water for drinking was very low and 'use after boiling' was also lower relative to 'use of purified water'. Also, the education on the environment should include the importance of the use of the tap water to improve the awareness of the citizen on the tap water and the administrative role, typically for educational institutes and schools, might be required to increase the use of the tab water for drinking.

• Environmental Analysis Health and Toxicology
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• v.17 no.2
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• pp.125-133
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• 2002

Volatile disinfection by-products (DBPs) contained in chlorinated tap water are released into household air during indoor activities (showering, cooking, dish -washing, etc.) associated with tap water uses and may cause adverse health effects on humans. Twenty seven subjects were recruited and their homes were visited during the winter of 2002. Tap water, household air, and exhaled breath samples were collected and analyzed for five volatile DBPs (chloroform, bromodichloromethane, dichloroacetonitrile, 1,1 -dichloropropanone and 1,1,1 trichloropropanone). Chloroform was a major DBP found in most samples. Tap water chloroform concentrations were not statistically correlated with its household air concentrations, probably due to individual variability in indoor activities such as showering, cooking, and dish - washing as well as household ventilation. Correlation of breath chloroform concentration with household air chloroform concentration showed its possible use as a biomarker of exposure to household air chloroform. Exposure estimates suggested that inhalation during household stay be a major route of exposure to volatile DBPs and that ingestion of tap water be a trivial contributor to the total exposure in Koreans.

• Journal of environmental and Sanitary engineering
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• v.9 no.1
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• pp.17-28
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• 1994

There are many possibilities that may lead to low quality of drinking water Recently, some unknown deposits in tap water raised a lot of public concern regarding the safety of drinking water in Seoul. We analyzed the quality of tap water from several areas of Seoul, including the area where public complaints about tap water were high. The results shows that the quality of tap water in Seoul was good, well below the environmental standards. Only the tap water from the area with high public complaints showed turbidity higher than that of other area. Also, result shows that component of deposit in tap water was Al, Fe, Mn, and Zn. Based on the research result we propose several measures that might help to reduce the amount of deposit in tap water as follows : 1 Using coagulant aid when coagulating or adjusting pH when filtering. 2. Replacing old water pipeline with new corrosive- resistant one. 3. Increasing water treatment efficiency by enhancing water treatment system such as automation of water treatment system adjusting production capacity, and improving operational condition of filler basin. 4. Chlorine disinfection at the distribution reservoir would help maintaining the same pH level and chlorine concentration throughout the water pipeline and reduce corrosion of pipe.

• Proceedings of the Microbiological Society of Korea Conference
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• 2000.05a
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• pp.94-101
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• 2000

We investigated the viral contamination of water environment including tap water in Korea. River water used for source water was analyzed about monthly between 1997 and 1999 over a period 26 months. A total of 22 tap water samples were collected in 10 sites in 2 urban areas between 1997 and 1998 over a 11 months. All samples were examined for infectious enteroviruses and adenoviruses by a cell culture technique followed by PCR amplification. To identify the recovered viruses from tap water, sequence analysis of PCR products was performed. Infectious viral particles were detected in river water all year round, ranging from 0.93 to 17.3 Most Probable Number of Infectious Unit (MPNIU) /100L. Tap water samples also contained infectious viral particles. The frequency of enteroviruses and adenoviruses in tap water were $50.0\%$ (11/22) and $36.7\%$ (8/22), respectively. Both enteroviruses and adenoviruses were detected in five tap water samples $(22.7\%)$. The level of viral contamination in tap water was quite high, ranging from 0.2 to 2.9 MPNIU/100L, far above the recommended virus level in drinking water set by the U.S. EPA. Poliovirus type 1 derived from vaccine was frequently detected and the remainder comprised coxsackievirus B type or echovirus type 6, which were causative agents of aseptic meningitis in Korea in 1997 and 1998, respectively. Several types of adenovirus were detected in tap water samples and some water samples were found to contain adenoviruses which were closely related to enteric adenovirus type 40 and 41. This stusy shows that surface water and tap water in Korea may be exposed to the risk of viral contamination, especially from recently recognized viruses and this constitutes a potential public health hazard.

• Corrosion Science and Technology
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• v.11 no.6
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• pp.232-241
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• 2012

This work focused on corrosion of carbon steel bolted GECM/Al parts in tap water and NaCl solutions. In tap water and NaCl solutions, open circuit potential of GECM and its potentials in a series of carbon steel bolt>Ti>Al became active. Regardless of test materials, open circuit potentials in tap water were noble, and increasing NaCl concentration, its potentials became active. Immersion test of single specimen showed that no corrosion occur in Ti and GECM. In tap water, carbon steel bolt didn't show red corrosion product and in chloride solutions, corrosion rate in 1% NaCl solution was greater than its rate in 3.5% NaCl solution and red corrosion product in 1% NaCl solution was earlier observed than that in 3.5% NaCl solution. It seems that this behavior would be related to zinc-coatings on the surface of carbon stee l bolt. On the other hand, aluminium was corroded in tap water and chloride solutions. Corrosion of aluminium in tap water was due to the presence of chloride ion in tap water by sterilizing process.

• Journal of Korean Society of Water and Wastewater
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• v.29 no.2
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• pp.155-163
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• 2015

Many advanced treatment processes have been introduced to WTPs, however, the consumer confidence on tap water is still low and the percentage of drinking water directly from the tap is less than 2 %. One of the methods to improve the credibility of tap water is to introduce a drinking water certification system. By introducing the system, water treatment processes can be optimized, which in turn, can significantly improve drinking water quality. In this paper, 6 water quality parameters(i.e., turbidity, CT, residual chlorine, geosmin, 2-MIB, Mn) which have significant influences on tap water quality and consumer confidence were identified, and their recommended guidelines were proposed. 3-Star or 5-Star certification can be awarded to the WTPs which have met the certification criteria. The drinking water certification system can be carried out as a voluntary program among drinking water suppliers.

• Journal of Korean Society of Water and Wastewater
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• v.25 no.5
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• pp.731-739
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• 2011

To investigate corrosivity characteristics of tap water in Korea, Langelier index (LI) of 30 multi-regional water treatment plants (WTPs) were evaluated. Weekly LI values of 30 WTPs were all negative, which means tap water in Korea might be very corrosive. Maximum LI decrease through water treatment processes was 0.95 under no additional corrosion control process. Based on the correlation results between LI and tap water qualities, pH and calcium concentration were confirmed as major parameters for LI control. Addition of calcium hydroxide with $CO_{2}$ or calcium hydroxide or sodium hydroxide can be chosen based on water quality. Continuous monitoring of LI and related parameters is recommended in water distribution system.