• 대한환경공학회지
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• 제27권5호
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• pp.461-467
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• 2005

내분비계장애물질로 분류된 phthalate esters의 제거방법에 대해 연구하였다. 상수처리조건에서 회분식으로 제거실험을 한 결과 응집침전은 $26.6{\sim}33.8%$, 오존산화에서는 $10{\sim}15%$ 제거효율을 나타내었다. 상수처리조건에서 활성탄 흡착에 의해 효과적으로 제거되는 것으로 나타났고 연속공정에서 EBCT를 10분 운전했을 때 원수의 phthalate esters농도가 $100\;{\mu}g/L$일 경우 WHO 및 US EPA 먹는 물 기준 달성이 가능한 것으로 나타났다. Pilot plant 실험결과 응집침전공정에서 $32{\sim}44%$, 사여과 공정에서는 $6{\sim}10%$, 오존산화공정에서 $8{\sim}10%$의 제거효율을 보였으며 활성탄 흡착공정을 거친 후에는 4가지 물질(DEP, DBP, BBP 및 DEHP)모두 검출되지 않았다. 실제 고도처리 정수장에서의 공정별 phthalate esters 제거율은 응집침전 공정에서 $29{\sim}76%$ 정도 제거되었고 모래여과 공정에서 $3{\sim}29%$, 오존산화 공정에서 $17{\sim}22%$ 제거되었으며, 활성탄 처리 후에는 4가지 물질 모두 검출되지 않았다.

• Journal of Animal Science and Technology
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• 제47권3호
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• pp.481-490
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• 2005

Nitrate contamination in water system is a critical environmental problem caused by excessive application of chemical fertilizer and concentration of livestock. In order to prevent further contamination, therefore, it is necessary to understand the origin of nitrate in nitrogen loading sources and manage the very source of contamination. The objective of this study was to examine the nitrate contamination sources in different agricultural system by using nitrogen isotope ratios. Groundwater and runoff water samples were collected on a monthly basis from February 2003 to November 2003 and analyzed for nitrogen isotopes. The nitrate concentrations of groundwater in livestock fanning area were higher than those in conventional and organic fanning area and exceeded the national drinking water standard of 10mg N/ l. The ${\delta}^{15}N$ranges of chemical fertilizer and animal manure were - 3.7${\sim}$+2.3$\textperthousand$ and +12.5${\sim}$26.7$\textperthousand$, respectively. The higher ${\delta}^{15}N$ of animal manure than those of chemical fertilizer reflected isotope fractionation and volatilization of '''N. The different agricultural systems and corresponding average nitrate concentrations and ${\delta}^{15}N$ values were: conventional farming, 5.47mg/e, 8.3$\textperthousand$; organic fanning, 5.88mg/e, 10.1$\textperthousand$; crop-livestock farming, 12.5mg/e, 17.7%0. These data indicated that whether conventional or organic agriculture effected groundwater and runoff water quality. In conclusions, relationship between nitrate concentrations and ${\delta}^{15}N$ value could be used to make a distinction between nitrate derived from chemical fertilizer and from animal manure. Additional investigation is required to monitor long-term impact on water quality in accordance with agricultural systems.

• 한국수처리학회지
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• 제26권6호
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• pp.109-115
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• 2018

This study was conducted to solve the water shortage problem by reclaiming urine from homes or public places and using it as cleaning water for toilets. The process used in this experiment is a chemical oxidation process combining ozone, hydrogen peroxide, and UV. We set the key substance that is to be removed as chromaticity and conducted the experiment to remove it. If the quantity or concentration of injected ozone, UV, and hydrogen peroxide is insufficient, then the chromaticity will initially increase due to low oxidizing power, and will later decrease. In addition, the efficiency of removing chromaticity appeared to be higher, depending on the quantity of ozone injected, for medium concentrated urine than highly concentrated urine. However, the absolute quantity of removed chromaticity was about 68% higher for highly concentrated urine, when 16 g/hr of ozone was injected. The higher the pH level, the reaction time and efficiency of removing chromaticity were higher, and in normal conditions, in reference to a pH of 8.55, there was a 6% difference in efficiency between a pH level of 5.05 and a pH level of 10.12. Finally, when processing urine through an ozone-only process, COD decreased steadily over time, but DOC did not decrease. This is because ozone reacts selectively with organic matter.

• Journal of Preventive Medicine and Public Health
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• 제6권1호
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• pp.133-160
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• 1973

1. Introduction Community medicine with the concept of comprehensive medical care and an ideal medical care delivery system not only for an individual or family but for the whole community has emerged. In April 1970, the Presbyterian Medical Center started a hospital based community health service project in order to improve the health of the people in rural areas. Prior to commencing a comprehensive medical care system, a family survey was needed. The major objective of this survey was to obtain information concerning the people and their environment so as to be able to plan and implement a comprehensive medical care program in Soyang-Myun. 2. Survey Method An interview using a family record form was carried out for each household. This family record form was designed to get information about demography, family planning, environmental sanitation and vital statistics. Prior to beginning, the members of the survey team were trained in interviewing techniques for three days. The team consisted of a public health nurse, four nurse-aides, a sanitarian and four health extension workers who are working in our project, The survey was carried out during the period November 1971 to March 1972. 3. Project area 1) Population of Soyang-Myun was 11,668; male, 5,962 and female, 5,706. Sex ratio: 104.5. 2) Households : 1,858 3) Family size: The average household consisted of 6.3 persons. 4) Educational level of householder a. Illiterate 13% b. No schooling but able to read 10% c. Preschool children 19% d. Primary school 47% e. Middle school 7% f. High school 3% g. College or University 1% 5) Occupational distribution of householders a. Farmer 67% b. Laborer 13% c. Office worker 4% d. Merchant 4% e. Industrial worker 2% f. Unemployed 8% g. Miscellaneous 2% 6) Religious affiliation a. No religion 74% b. Buddhist 12% c. Protestant 10% d. Catholic 4% 4. Survey results Living Environment : a. Home ownership 95% b. Kinds of roofing Straw-thatched house 84% Tile-roofed house 10% Slate-roofed house 5% Other 1% c. Floor space Less than 6 pyong 10% 6-10 pyong 53% 11-15 pyong 24% 16-20 pyong 9% More than 20 pyong 4% d. Radio ownership 80% Environmental Sanitation : a. the source of drinking water public well 49% private well 30% drainage water 9% steam water 8% well pump 3% water distribution system 1% b. Distance between well and toilet more than 16meters 38% 6-10 meter 31% 11-15 meters 14% Less than 6 meters 17% c. The status of well management Bad 72% Fair 26% Good 2% d. General sanitary state of house Bad 37% Fair 51% Good 12% e. House drainage system had no house drainage. 77% Family Planning : a. 24% of the people have used contraceptives, but 12% ceased to use them. 76% have never used contraceptives. b. used methods 1oop 68% oral pill 16% vasectomy 4% condom 1% tubal ligation 1% two or more methods 10% Maternal Health : a. The number of conceptions of housewives under 50 years of age. 11 times 26% 6 times 11% 5 times 11% 4 times 9% b. The place of delivery own house 88% hospital 1% others 11% Treatment of general sickness : a. The place of treatment Soyang Health Center 31% Hospital (private or otherwise) 26% Pharmacy 14% Herb medicine 5% Private care 5% No treatment 12% Miscellaneous 7% b. Usual causes of diseases Unknown 46% Tuberculosis 29% Neuralgia 8% CVA 3% Bronchitis 3% Others 11%

• 미생물학회지
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• 제38권3호
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• pp.198-204
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• 2002

폴리오 바이러스는 전형적인 장관계 바이러스로 마비, 무균성 수막염, 뇌염 등을 유발한다. 폴리오 바이러스는 분변-구강 경로를 통해 전파되며, 오염된 물을 음용수로 사용할 시 공중 보건에 문제가 될 수 있으므로 먹는 물에서 폴리오 바이러스를 검출하는 것은 중요하다. 감염성이 있는 바이 러스와 불활성화(열처리와 자외선 처리)시킨 바이러스를 세포배양법, 역전사 중합효소 연쇄반응법(reverse transcription-polymerase chain reaction: RT-PCR)그리고 세포배양-중합효소 연쇄반응 통합법(integrated cell culture-PCR: ICC-PCR)으로 검출 실험을 했다. 감염성이 있는 폴리오 바이러스는 세 가지 방법으로 모두 검출이 되었으며, 이 중에서 바이러스를 검출하는데 ICC-PCR 방법이 가장 민감했다. 세포배양법은 적은 수의 바이러스를 검출하는데 약 2주의 긴 시간이 걸렸다. 열처리나 자외선 처리로 불활성화된 바이 러스는 세포배양과 ICC-PCR방법으로는 검출이 되지 않았다. 자외선 처리한 바이러스는 RT-PCR 방법으로 검출되지 않았으나 열처리한 바이러스는 검출되었다. RT-PCR 방법은 감염성 바이러스뿐 아니라 불활성화된 바이러스도 검출할 수 있으므로 감염성이 있는지 없는지를 구분할 수 없는 단점이 있다. 이와 같은 결과는 감염성 있는 바이러스를 가장 민감하고 효과적으로 검출하는 방법이 ICC-PCR 방법이라는 것을 제시하여 준다.

• 농촌의학ㆍ지역보건
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• 제43권4호
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• pp.258-269
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• 2018

2018년 6월 12일 충청북도 옥천군 소재 A고등학교에서 노로바이러스의 유행을 지연신고하는 사례가 발생하였고, 이에 대한 원인과 전파양식 등을 규명하고 예방 및 관리대책을 마련 하기 위하여 역학조사를 수행하였다. A고등학교 학생 183명을 대상으로 설문조사, 환례자 60명, 조리종사자 10명을 대상으로 세균 10종 및 바이러스 5종에 대한 검체검사를 실시하였다. 설문조사는 최초환자 발생일 6월 5일을 기준으로 3일 전인 6월 2일부터 12일까지의 식단을 이용하여 환자-대조군 조사를 시행하였다. 학생, 교직원, 조리종사자 785명 중 환례는 61명으로 노로바이러스의 발병률은 7.8% 이었다. 위험요인 분석에서 정수기 음용수가 유의한 변수이었다. 검체검사에서 학생 2명, 정수기 음용수, 환경검체에서 동일 유형의Norovirus GI-8이 검출되었다. 이번 유행의 원인으로 본관, 기숙사, 급식실 정수기 음용수가 오염되고 그로 인해 원인병원체 노로바이러스의 전파가 이루어졌다고 판단하였다. 이번 연구는 6월 5일 첫 환례자가 발생했음에도 신고가 7일이 경과한 6월 12일 지연신고 되어 장관감염증 확산 조기차단이 이루어지지 않아 환례자가 더 많이 발생한 것으로 추정된다. 향후 학교급식 시 발생하는 수인성 및 식품매개성질병으로부터 학생을 보호하고 집단발생을 예방하기 위하여 학생의 증상을 가장 우선적으로 파악이 가능한 담임선생님과 보건교사의 공조체제 개선, 보건교사 부재 시 대응방안, 보건교사의 학교 감염병 집단발생에 대한 인식제고를 위한 시스템 보완이 이루어져야 할 것이다. 또한 질병관리본부의 기본 역학조사서 서식에 지연신고에 대한 사유를 기록하는 항목을 추가하여 지연신고에 대한 원인에 대한 규명과 그에 따른 대책을 마련해야 할 것이다.

• Journal of Preventive Medicine and Public Health
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• 제38권2호
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• pp.189-196
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• 2005

Objectives: An outbreak of shigellosis occurred among students and staff of S primary and middle school, Seongju-gun, in 2003. This investigation was carried out to institute an effective counterplan, and study the infection source and transmission of the shigellosis. Methods: The authors conducted a questionnaire survey among 235 students and staff from S preschool, primary and middle school relating to the ingestion of school lunch and the manifestation of symptoms. Also, the author investigated the drinking water, feeding facility and reconstructed cooking process of the food presumed to be the cause of the shigellosis. The diarrhea cases were defined as confirmed cases and those cases who had had diarrhea more than one time, accompanied with symptoms such as fever, vomiting and tenesmus. Results: From rectal swabs 20 people, between June 28 and July 4, 2003, were confirmed with shigellosis. The diarrhea attack rate was 40.0%. Those who had ingested tomatoes and cubed radish kimchi had significantly higher diarrhea attack rates (p<0.05), with the relative risk of tomatoes being 2.69 (95% CI: 0.98-7.42). The major cause of shigellosis was presumed to be from contaminated tomatoes due to cooking with rubber gloves containing holes. Conclusion: The cooks in charge of school lunches must make doubly sure to not only attend to their sanitation, but also to manage the table wear and items used in providing school lunches. The health care authority should introduce higher-leveled criteria for health care among cooks, so that they cannot cook when the have a case of any infectious disease.

• Journal of Preventive Medicine and Public Health
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• 제44권4호
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• pp.185-189
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• 2011

Objectives: In 1995, an outbreak survey in Gozan-dong concluded that an association between fiberglass exposure in drinking water and cancer outbreak cannot be established. This study follows the subjects from a study in 1995 using a data linkage method to examine whether an association existed. The authors will address the potential benefits and methodological issues following outbreak surveys using data linkage, particularly when informed consent is absent. Methods: This is a follow-up study of 697 (30 exposed) individuals out of the original 888 (31 exposed) participants (78.5%) from 1995 to 2007 assessing the cancer outcomes and deaths of these individuals. The National Cancer Registry (KNCR) and death certificate data were linked using the ID numbers of the participants. The standardized incidence ratio (SIR) and standardized mortality ratio (SMR) from cancers were calculated by the KNCR. Results: The SIR values for all cancer or gastrointestinal cancer (GI) occurrences were the lowest in the exposed group (SIR, 0.73; 95% CI, 0.10 to 5.21; 0.00 for GI), while the two control groups (control 1: external, control 2: internal) showed slight increases in their SIR values (SIR, 1.18 and 1.27 for all cancers; 1.62 and 1.46 for GI). All lacked statistical significance. All-cause mortality levels for the three groups showed the same pattern (SMR 0.37, 1.29, and 1.11). Conclusions: This study did not refute a finding of non-association with a 13-year follow-up. Considering that many outbreak surveys are associated with a small sample size and a cross-sectional design, follow-up studies that utilize data linkage should become standard procedure.

• 한국환경보건학회지
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• 제47권1호
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• pp.87-100
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• 2021

Objectives: The purpose of this study was to analyze the factors affecting Bisphenol A (BPA) exposure in children and adolescents using the results of the Korean National Environmental Health Survey (KoNEHS) cycle 3. Methods: A total of 2,380 subjects (n=571, 887, and 922 for 3-5, 6-11, and 12-17 years of age, respectively) were analyzed using an environmental exposure survey and environmental chemical substances concentration levels. Univariable linear regression analysis was performed to determine associated variables such as sex, age, income level, housing type, secondhand smoke time, cup noodles and canned food consumption, seafood consumption, new furniture (within the previous six months), drinking water type, and consumption of herbal medicines. Variables with p-values of less than 0.2 were extracted from the results and a multivariable linear regression analysis was performed using stepwise selection. Results: Univariable linear regression analysis showed positive associations between BPA concentration levels and variables including sex, age, secondhand smoke time, new furniture (within the previous six months), renovated living space (within the previous six months), fish and shellfish consumption, plastic-bottled drink consumption, and herbal medicine. As a result of performing multivariable linear regression analysis, the lower was the age the higher was the concentration of BPA levels. Additionally, women showed higher BPA levels than those of men. The more frequently fish was consumed, the higher was the BPA concentration. Moreover, higher BPA concentrations were observed when taking herbal medicine. Conclusions: The main factors affecting BPA concentration levels were age, gender, and consumption of fish and herbal medicine.

• 동의생리병리학회지
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• 제16권5호
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• pp.899-904
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• 2002

For determination of the genotoxicity of VOCs(Volatile Organic Compounds) in water, in vitro Comet assay was performed using 3T3 cells. The selected 5 VOCs; Trichloroethylene(TCE), Tetrachloroethylene(PCE), Carbontetrachloride (CteC), Dichloromethane(DCM) and Chlorofrom(Chl) and mixed solvent(Mix), are the test items for drinking water quality. Author analyzed the genotoxicity of these solvents through their tail length (TL) values. Mix, PCE, Chl, TCE in order had cytotoxicity at the highest concentration, and CCl₄ and DCM had no cytotoxic effect. TCE, CCl₄, Chl, PCE, Mix, DCM had genotoxicity, Chl, PCE, Mix had both cytotoxicity and genotoxicity simultaneously, Cytotoxic effect of mixed organic solvents, compared with that of single component, at each concentration, was influenced by the synergistic effect of the interaction of each organic component.