• 한국환경보건학회지
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• 제45권6호
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• pp.561-568
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• 2019

Objectives: The most commonly detected heavy metals in rocks and soils, including Pb, Cd, Cu, Fe, Mn and As, are representative pollutants discharged from abandoned mines and have been listed as potential sources of contamination in drinking water. This study focused on increasing the removal efficiency of heavy metals from drinking water resources by surface modification of natural adsorbents to reduce potential health risks. Methods: Iron oxide coating and graft polymerization with zeolites and talc was conducted for bipolar surface modification to increase the combining capacity of heavy metals for their removal from water. The removal efficiency of heavy metals was measured before and after the surface modification. Results: The removal efficiency of Pb, Cu, and Cd by surface modified zeolite showed 100, 92, and 61.5%, respectively, increases compared to 64, 64, and 38% for non-modified zeolite. This implies that bipolar surface modified natural adsorbents have a good potential use in heavy metal removal. The more interesting finding is the removal increase for As, which has both cation and anion characteristics showing 27% removal efficiency where as non-modified zeolite showed only 2% removal. Conclusions: Zeolite is one of the most widely used adsorptive materials in water treatment processes and bipolar surface modification of zeolite increases its applicability in the removal of heavy metals, especially As.

• 과학교육연구지
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• 제32권1호
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• pp.73-84
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• 2008

이 연구의 목적은 구미 지역 주부들의 먹는 물과 물 환경에 대한 인식을 조사하여, 주부들의 먹는 물로서의 수돗물과 수돗물 오염에 대한 생각들을 알아보고자 하였다. 연구 대상은 구미 지역 주부 20명을 대상으로 먹는 물과 물 환경에 대한 질문지를 작성하게 하여 그 결과를 분석하였다. 연구 결과로 첫째, 대상자들은 구미 지역에 영향을 미치는 자연 자원으로서의 먹는 물과 물 환경에 대한 관심이 높았다. 또한 대상자의 35%는 정수기로 정수된 물을 마시고, 30%는 수돗물을 끓여서 마시고 있는 것으로 조사되었다. 수돗물의 안전성에 대해서는 75%였으나, 먹는 물의 안전성은 상대적으로 낮게 인식하고 있었다. 둘째, 주부들은 먹는 물 보전 캠페인과 능동적인 참여가 지역 사회와 연계할 때 더욱 효과적이라고 주장하였다. 더욱이 먹는 물과 물 환경에 대한 지속적인 교육을 통해 먹는 물로서의 수돗물에 대한 인식이 촉진될 수 있다고 하였다.

• 한국환경교육학회지:환경교육
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• 제24권4호
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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.

• 상하수도학회지
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• 제21권1호
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• pp.37-46
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• 2007

A feasibility test was conducted to evaluate the addition of turbidity substance in a coagulation process to remove natural organic matters (NOM), the precursor of disinfection by-products (DBPs). The experimental water sources were synthetic water containing 5 mg/L of humic acid and 50 mg/L of NaHCO3 and drinking water resource of Ulsan city (S Dam water, D Dam water and Nak-Dong raw water). The examined turbidity substances were kaolin, acid clay, and modified clay (0.38 meq $NH_4{^+}-N/g$ clay). In Jar tests at different concentrations of the turbidity substances (5, 10, 15, 20, 30 mg/L) using the synthetic water, the turbidity substances improved the removal of turbidity, UV-254 absorbance and dissolved organic carbon (DOC) by 23.8-38.1%, 17.0-24.5% and 2.5-44.5%, respectively. The modified clay showed higher removal efficiencies than other substances. In Jar tests using the drinking water, 10 and 20 mg/L of modified clay enhanced the removal efficiencies of turbidity, UV-254 absorbance, DOC, trihalomethane formation potential (THMFP), and haloacetic acid formation potential (HAAFP) by 3.0~4.3%, 19.1~29.0%, 12~34.9%, 4.9~36.7%, and 1.6~30.2%, respectively.

• 한국지하수토양환경학회지:지하수토양환경
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• 제23권6호
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• pp.9-27
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• 2018

In recent years, the sales of bottled spring water (BSW) have been drastically increasing in Korea and other countries, which accompanied great interests in conservation and reclamation of natural mineral water (NMW). In this study, management and research activities on NMW in Europe, USA, and Codex Alimentarius were reviewed. In each region, NMW is regulated with its own quality standards that differ from ordinary drinking water, and management actions are strictly implemented to protect water resources and to secure quality of NMW. Many studies on NMW were carried out for monitoring inorganic constituents including major and trace elements in national levels for bottled NMW, groundwater, and tap water in other countries. In Korea, NMW became commercialized in 1995 when BSW was legally approved as a drinking water. To further promote utilization of various types of NMW in Korea, regulations and policies for NMW need to be revised in accordance with international NMW management trends. Further, studies of NMW that compile a comprehensive set of physical and chemical parameters of NMW are also needed to properly understand occurrences, hydrogeological and geochemical processes of NMW, as well as to evaluate its potential use as a natural resource.

• 한국광물학회지
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• 제27권4호
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• pp.235-242
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• 2014

우라늄은 자연적 원인과 인위적 원인에 의해 오염이 가능하지만 국내 지하수 토양환경에서는 자연적 원인에 의한 오염 가능성이 높다. 우라늄은 방사성 독성과 화학적 독성을 동시에 갖고 있어 먹는 물에 포함될 경우 그 위해성이 매우 높다. 본 연구에서는 경북지역의 마을상수도 및 소규모 급수시설, 지하수, 샘물 및 먹는 샘물, 먹는 물 공동시설, 지하수 측정망, 민방위비상급수 등의 시료를 대상으로 우라늄 농도를 측정하였으며 국내외 수질 기준과 비교하여 오염 정도를 평가하였다. 총 803개의 시료 중 미국의 먹는 물 권고기준 또는 우리나라의 권고기준인 $30{\mu}g/{\ell}$를 초과하는 시료의 수는 6개이며 전체시료에서 차지하는 비율은 0.7%이다. 모암의 특성에 따른 우라늄의 농도는 흑운모화강섬록암, 흑운모화강암, 편마상화강암 등과 같은 화강암질 암석이 분포한 지역에서 비교적 높게 나타났다.

• Environmental Analysis Health and Toxicology
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• 제26권
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• pp.2.1-2.7
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• 2011

Objectives: N-Nitrosodimethylamine (NDMA) is classified as a probable human carcinogen by the United States Environmental Protection Agency (US EPA) and is formed during the chlorination of municipal drinking water. In this study, selected nitrosamines were measured in chlorinated drinking water collected from Chuncheon, Kangwon-do, Republic of Korea, and a risk assessment for NDMA was conducted. Methods: Twelve water samples were collected from 2 treatment plants and 10 household taps. Samples were analyzed for 6 nitrosamines via solid-phase extraction cleanup followed by conversion to dansyl derivatives and high-performance liquid chromatography-fluorescence detection (HPLC-FLD). Considering the dietary patterns of Korean people and the concentration change of NDMA by boiling, a carcinogenic risk assessment from ingestion exposure was conducted following the US EPA guidelines. Results: NDMA concentrations ranged between 26.1 and 112.0 ng/L. NDMA in water was found to be thermally stable, and thus its concentration at the end of boiling was greater than before thermal treatment owing to the decrease in water volume. The estimated excess lifetime carcinogenic risk exceeded the regulatory baseline risk of $10^{-5}$. Conclusions: This result suggests that more extensive studies need to be conducted on nitrosamine concentration distributions over the country and the source of relatively high nitrosamine concentrations.

• 수도
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• 통권67호
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• pp.51-67
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• 1994

• Korean Membrane Journal
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• 제11권1호
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• pp.21-28
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• 2009

We investigated the effect of organic materials on membrane fouling in advanced drinking water treatment by a hybrid module packed with granular activated carbon (GAC) outside multi-channel ceramic microfiltration membrane. Synthetic water was prepared with humic acid and kaolin to simulate natural water resouces consisting of natural organic matter and inorganic particles. Kaolin concentration was fixed at 30 mg/L and humic acid was changed as 2~10 mg/L to inspect the effect of organic matters. Periodic back-flushing using permeate water was performed for 10 sec per filtration of 10 min. As a result, both resistance of membrane fouling (Rf) and permeate flux (J) were influenced highly by concentration of humic acid. It proved that NOM like humic acid could be an important factor on membrane fouling in drinking water treatment. Turbidity and UV254 absorbance were removed up to above 97.4% and 59.2% respectively.

• Journal of Microbiology and Biotechnology
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• 제16권7호
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• pp.1060-1067
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• 2006

This study was undertaken to determine the effect of reservoirs on water quality and the distribution of pathogenic and indicator bacteria in a drinking water distribution system (total length 14km). Raw water, disinfected water, and water samples from the distribution system were subjected to physicochemical and microbiological analyses. Most factors encountered at each season included residual chloride, nitrate, turbidity, and phosphorus for heterotrophic bacterial distribution, and hardness, heterotrophic bacteria, sampling site, and DOC (dissolved organic carbon) for bacteria on selective media. No Salmonella or Shigella spp. were detected, but many colonies of opportunistic pathogens were found. Comparing tap water samples taken at similar distances from the water treatment plant, samples that had passed through a reservoir had a higher concentration of heterotrophic bacteria, and a higher rate of colony formation with 10 times as many bacteria on selective media. Based on the results with m-Endo agar, the water in reservoirs appeared safe; however, coliforms and opportunistic pathogenic bacteria such as Pseudomonas aeruginosa were identified on other selective media. This study illustrates that storage reservoirs in the drinking water distribution system have low microbiological water quality by opportunistic pathogens, and therefore, water quality must be controlled.