• Title/Summary/Keyword: agricultural contamination

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Effect on Quality Change of Cherry Tomato by $CO_2$ Concentration of Flushed Gas and Storage Period (충전가스의 $CO_2$ 함량 및 노출기간의 변화가 방울토마토의 품질변화에 미치는 영향)

  • Lee, Seung Yuan;Lee, Seung Jae;Choi, Dong Soo;Hur, Sun Jin
    • Culinary science and hospitality research
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    • v.20 no.6
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    • pp.200-210
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    • 2014
  • The purpose of this study was to investigate the quality changes and contamination of microorganisms such as Escherichia coli, mold and yeast in cherry tomatoes during storage at different temperatures, gas composition and periods(7 and 14 days). This study determined pH, color change and the growth pattern of microorganisms in cherry tomato during storage at $5^{\circ}C$, $10^{\circ}C$ and $15^{\circ}C$. According to the results, pH level was a little raised with storage period. On average, $L^*$, $a^*$ and $b^*$ value of cherry tomato were irregular value of increase and decrease of all gas packaging with storage period. In regard of the types of microorganism, aerobic count plate, coliform count, mold and yeast were detected when cherry tomatoes were stored at $5^{\circ}C$, $10^{\circ}C$ and $15^{\circ}C$ during storage for 14 days. Equally, all microorganisms of cherry tomato were irregular with storage period and complex gas packaging. However, this study determined that packaging with a higher $CO_2$ concentration than $O_2$ concentration can reduce growth of microorganism. These studies can be used as primary data for determining the optimal complex gas to storage enlargement.

Hydrogeochemical study of a watershed in Pocheon area: controls of water chemistry

  • Kim, Kyoung-Ho;Yun, Seong-Taek;Chae, Soo-Ho;Jean, Jong-Wook;Lee, Jeong-Ho;Kweon, Hae-Woo
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2004.09a
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    • pp.121-121
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    • 2004
  • The groundwater in the Pocheon area occurs from both a fractured bedrock aquifer in igneous and metamorphic rocks and an alluvial aquifer with a thickness of <50 m, and forms a major source of domestic and agricultural water supply. In this study, we performed a hydrogeochemical study in order to identify the control of geochemical processes on groundwater quality. For this study, groundwater level and physicochemical parameters (EC, Eh, pH, alkalinity) were monitored once a month from a total of 150 groundwater wells between June 2003 to August 2004. A total of 153 water samples (13 surface water, 66 alluvial groundwater, 74 bedrock groundwater) were also collected and analyzed in February 2004. Groundwater chemistry in the study area is very complex, depending on a number of major factors such as geology, degree of chemical weathering, and quality of recharge water. Hydrochemical reactions such as the leaching of surficial and near-solace soil salts, dissolution of calcite, cation exchange, and weathering of silicate minerals are proposed to explain the chemistry of natural groundwater. Alluvial groundwaters locally have very high TDS concentrations, which are characterized by their chloride(nitrate)-sulfate-bicabonate facies and low Na/Cl ratio. Their grondwater levels are highly fluctuated according to rainfall event. We suggest that high nitrate content and salinity in such alluvial groundwaters originates from the local recharge of sewage effluents and/or fertilizers. Likewise, high concentrations of nitrate were also locally observed in some bedrock groundwaters, suggesting their effect of anthropogenic contamination. This is possibly due to the bypass flow taking place through macropores. Tile degree of the weathering of silicate minerals seems to be a major control of the distribution of major cations (sodium, calcium, magnesium, potassium) in bedrock groundwaters, which show a general increase with increasing depth of wells. Thermodynamic interpretation of groundwater chemistry shows that the groundwater in the study area is in chemical equilibrium with kaolinite and Na-montmorillonite, which indicates that weathering of plagioclase to those minerals is a major control of hydrochemistry of bedrock groundwater. The interpretation of the molar ratios among major ions, as well as the mass balance calculation, also indicates the role of both dissolution/precipitation of calcite and Ca-Na cationic exchange as bedrock groundwaters evolves progressively.

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An Ethnography of the Concept of Illness by the Elderly (노인의 질병 관념에 관한 문화기술적 연구)

  • Cho, Myoung Ok
    • Korean Journal of Adult Nursing
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    • v.12 no.4
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    • pp.690-705
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    • 2000
  • This ethnography was based on Kleinman's explanatory model of a health care system. It is conducted to make thick discription of illness conception of the elderly in a sociocultural context. The basic assumptions were as follows. 1) A health care system is a cultural system, and as with any other cultural system, it is a system of symbolic meanings anchored in a particular arrangement of social institutions and patterns of interpersonal relationships; 2) In all societies health care activities are more or less interrelated. Therefore, they need to be in a holistic manner as socially organized responses to disease that constitute a special cultural system; health care system; 3) Health and illness experiences are the natural process of disease. Individuals who recognized a for state of health, their family, neighbors, and communities define the state, search for causes of the health problems, and response to it. According by, they proceed to search for healing stratagies. So, understanding of the illness experience is the starting point for health care. The study participants were 12 elders aged 60 or more. The fieldwork was conducted in an agricultural clan village of Namwon city. The data collection and analysis were cyclic, from descriptive observation, domain analysis, focused observation, taxanomic analysis, selected observation, componential analysis, and finally cultural themes were all analysed. Proxemic and text analysis techniques were used according to the characteristics of the data. The data of sociocultural context and descriptive data were collected from 1990 to 1992. Informations on illness concepts were collected during 1994 using focused observation. Data confirming and contrast observations were conducted from 1997 and 1999. Illness concepts of the elderly were taxonomized supernatural cause, non-supernatural cause, immediate cause, and ultimate cause. The supernatural ones were ancestors, god of home, god of village, and ghost such as 'sal(evil force of dead man)' and 'gagqui(ghost of begger)'. The non-supernatural ones were Ki, natural phenomenones, natural objects, foods, human and human behaviors. Immediate ones were insufficiency and overflows, discretion and consolidation, disorder and out of order, cloudness and contamination, and fluctuation and stagnation of supernatural cause and non-supernatural ones. Ultimate causes were intrusion and loss of supernatural and nonsupernatural ones. The cultural themes of illness concepts of the elderly are: 1) illness concepts are not based on causality principle, but on reciprocal principle; 2) illness concepts are affected by social level and charicteristics of the patients; 3) the causes of disease are recognized as imposed both positive and negative effects on health based on interpretation of the indiviuals; 4) illness concepts reflects on principles of everyday life of the society members such as hierachial structure and group cohesiveness; 5) illness concepts are ruled on principle of reciprocity and spread; 6) illness concepts are interrelated with physical environment of the participants. It can be concluded that the illness concepts of the elderly in a traditional clan village are a component of health care system as a cultural system based on these results. The these results can be a useful basis for gerontological nursing practice and education.

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Geochemical Investigation on Arsenic Contamination in the Alluvial Ground-water of Mankyeong River Watershed (만경강유역 충적대수층 지하수의 비소오염현황 및 지구화학적 특성)

  • Moon, Jeong-Tae;Kim, Kang-Joo;Kim, Seok-Hwi;Jeong, Cheon-Sung;Hwang, Gab-Soo
    • Economic and Environmental Geology
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    • v.41 no.6
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    • pp.673-683
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    • 2008
  • As-rich alluvial groundwaters occurring in the agricultural area of Mankyeong River watershed were geochemically studied. 15 out of 29 investigated wells (52%) showed As levels exceeding the WHO drinking water standard ($10{\mu}g/L$). Their chemistry is characterized by low Eh levels, low $NO_3$ and $SO_4$ concentrations, and high pH, alkalinity, Fe, $NH_4$, and $PO_4$ levels. This suggests that arsenic is enriched by the reductive dissolution of As-bearing Fe-/Mn-(hydro)oxides, the commonest process in Bangladesh and West Bengal of India, of which groundwaters are severely contaminated by As. It was also revealed that As concentrations in the area are strongly regulated by the presence of agrochemicals such as $NO_3$ and $SO_4$.

Natural Occurrence of Fumonisins $B_1$ and $B_2$ in Korean Corns (한국산 옥수수의 Fumonisin $B_1$$B_2$ 오염현황)

  • Yu, Chun-Cheol;Oh, Deog-Hwan;Park, Boo-Kil
    • Korean Journal of Food Science and Technology
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    • v.31 no.3
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    • pp.569-574
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    • 1999
  • One hundred and ninety seven corn samples, which collected from each local province in Korea between 1995 and 1996, were analyzed for fumonisin $B_1\;(FB_1)$ and $B_2\;(FB_2)$ contamination using fluometric HPLC. $FB_1$ and $FB_2$ were detected in 143 (72.6%) and 128 (62.4%) samples from 197 samples at the concentrations ranging from 0 to $224.2\;{\mu}g/g$ for $FB_1$ and from 0 to $60.0\;{\mu}g/g$ for $FB_2$, respectively. The total fumonisin levels analyzed from 143 samples were 15.4, 37.5 and 14% for concentrations below $10\;{\mu}g/g$, above $10\;{\mu}g/g$ and above $30\;{\mu}g/g$, respectively. The total fumonisin levels containing above $10\;{\mu}g/g$ were detected the highest concentration with 53.2% in samples collected from Kangwon, and followed by Kyeongki (45.0%), Cheonbuk (40.0%), Chungbuk (26.9%) and Kyeongbuk (11.1%). The total fumonisin level containing above $10\;{\mu}g/g$ in samples collected in 1996 was higher than that in 1995. Both fumonisin $B_1$ and $B_2$ from samples collected in 1995 were detected higher than that in 1996 and $FB_1$ was detected the highest level in samples collected from Kyeongki province and followed by Kangwon, Cheonbuk, Chungbuk and Kyeogbuk (11.1%). Also, similar results were observed in $FB_2$.

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Geochemical Characteristics and Nitrates Contamination of Shallow Groundwater in the Ogcheon Area (옥천지역 천부지하수의 지구화학적 특성 및 질산염 오염 특성)

  • Lee, In-Gyeong;Choi, Sang-Hoon
    • Economic and Environmental Geology
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    • v.43 no.1
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    • pp.43-52
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    • 2010
  • The geochemical and nitrogen isotopic analyses for shallow groundwater of Ogcheon area were carried out to characterize the geochemical characteristics of the groundwater and to identify the source of nitrate. Groundwater shows a neutral pH to weakly alkalic condition with pH values ranging from 6.9 to 8.4. The average of EC, Eh and DO is $344.2\;{\mu}s/cm$, 195 mV, 4 mg/L, respectively. According to piper diagram, chemical composition of groundwater is dominantly characterized by Ca-$HCO_3$ type. On the other hand, groundwater type in the study area include Ca-Cl+$NO_3$ type that were highly influenced by agricultural activities. $NO_3$-N concentration of the collected samples(n=45) range from 12.4 to 34.2 mg/l. These data show that the $NO_3$-N concentration exceeds Korea Drinking Water Standard (10 mg/l). The $\delta^{15}N-NO_3$ values range from $2.7^{\circ}/_{\circ\circ}$ to $18.8^{\circ}/_{\circ\circ}$. The enrichments of heavy isotope in the groundwater indicate that major origin of nitrate pollution were associated with animal and human waste. Also the denitrification may have partly contributed as one of the sources of nitrogen.

Developmental Toxicity of Alkylphenols in Amphibians: A Review (알킬페놀류 화합물의 양서류 발생독성: 종설)

  • Park, Chan-Jin;Ahn, Hae-Sun;Ahn, Hyo-Min;Gye, Myung-Chan
    • Korean Journal of Ecology and Environment
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    • v.44 no.2
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    • pp.103-112
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    • 2011
  • Aquatic contamination by organic pollutants has been a suspected reason for rapid decrease of amphibian populations whose embryonic and larval stages are in an aquatic environment. Amphibian embryos can be a useful model to study the ecoctoxicologial impacts of aquatic pollutants. The obtained toxicological data are useful references for the management of aquatic pollutants in public health because amphibia share many developmental events with terrestrial vertebrates including humans. Safety guidelines for the toxicological effects of aquatic contaminants of chemicals identified as hazardous should be addressed at multiple endpoints. Alkylphenols have been widely-used in agricultural, industrial, and household activities; they contaminate and can persist in aquatic environments. Exposure to alkylphenols results in endocrine disruption in aquatic animals. In this review, we summarize the developmental toxicities of alkylphenols in amphibian embryos and larva according to the exposure route, chemical concentration, duration of exposure, and affected developmental stage together with mechanisms of toxicity and typical patterns of developmental abnormality. The merits of amphibian embryos as a toxicity test model for mid- to long-term exposure to aquatic pollutants are discussed proposed.

Monitoring of Endocrine Disruptor-suspected Pesticide Residues in Greenhouse Soils and Evaluation of Their Leachability to Groundwater (시설재배 토양 중 내분비계장애 추정농약의 잔류 모니터링 및 지하수 용탈 가능성)

  • Noh, Hyun-Ho;Lee, Kwang-Hun;Lee, Jae-Yun;Park, Hyo-Kyung;Lee, Eun-Young;Hong, Su-Myung;Park, Young-Soon;Kyung, Kee-Sung
    • The Korean Journal of Pesticide Science
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    • v.15 no.4
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    • pp.441-452
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    • 2011
  • This study was carried out to survey the residual characteristics of endocrine disruptor (ED)-suspected pesticides in greenhouse soils and assess their leachabilites to groundwater. Greenhouse soils were collected from 40 sites of greenhouse in 2008 in Korea. Sixteen ED-suspected pesticides which had been using in Korea, such as alachlor, benomyl, carbaryl, cypermethrin, 2,4-D, dicofol, endosulfan, fenvalerate, malathion, mancozeb, metribuzin, metiram, methomyl, parathion, trifluralin, and vinclozolin, in the soils, were analyzed by chromatographic methods using GLC-ECD and HPLC-DAD/FLD. Limits of detection (LODs) of the test pesticides ranged from 0.0004 to 0.005 mg/kg. Recoveries of the target pesticides from soil ranged from 72.69 to 115.28%. Four pesticides including cypermethrin were detected in the range of from 0.001 to 2.019 mg/kg, representing that their detection rate from greenhouse soils was 37.5%. The highest detection rate was observed from endosulfan which was detected from 16 site soils of the total samples, indicating that endosulfan is persistent in soil because of its very low mobility and high adsorption characteristics in soil. Based on the groundwater ubiquity scores (GUSs) of the pesticides detected from greenhouse soils, most of them have little possibilities of groundwater contamination except the fungicide vinclozolin with some leaching potential because of high water solubility and very low soil adsorption property.

Epidemiological Investigation on an Outbreak of Enterotoxigenic E. coli among the Baseball Club Students of High School in Ulsan City, 2014 (2014년 울산시 일개 고등학교 야구부원들에서 발생한 장독소생성대장균의 유행에 관한 역학조사)

  • Kang, Young-Eun;Lim, Hyun-Sul;Lee, Kwan;Kim, Byung-Seok
    • Journal of agricultural medicine and community health
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    • v.40 no.2
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    • pp.53-61
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    • 2015
  • Objectives: An outbreak of food poisoning occurred among the baseball club students at a high school in Ulsan city in 2014. An epidemiological investigation was carried out to examine the infection source and the transmission route of pathogen, and to prevent a recurrence. Methods: A questionnaire survey was conducted for 26 male students and 2 food handlers. Rectal swabs were examined in 7 students and the 2 food handlers, and an environmental investigation was performed. A retrospective cohort study was used to evaluate the association between risk factors and disease. Results: The attack rate was 35.7% (10 persons/28 persons) from June 9 to 14, and Enterotoxigenic E. coli ST/LT was isolated from 7 among 28 persons. The study revealed that no food was a significant risk factor for the outbreak. There were no connection between environmental factors and the outbreak. Conclusions: The major risk factors for this outbreak were presumed to be the contaminated ice cube and ice making machines and eating ice cube from the machines. More strict personal and environmental hygiene need to be enforced to prevent such outbreaks.

Comparison of Pipeline and Clamshell Capping Technologies for the Remediation of Contaminated Marine Sediments (해양 오염퇴적물 정화를 위한 원통관과 클램쉘을 이용한 피복 기술의 비교)

  • Kang, Ku;Hong, Seong-Gu;Kim, Young-Kee;Park, Seong-Jik
    • Journal of Navigation and Port Research
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    • v.41 no.4
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    • pp.195-206
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    • 2017
  • In situ capping technology for marine sediment pollution control has never been applied in South Korea. In this study a pilot project for the capping was carried out in Busan N Harbor. Pipeline and clamshell capping technologies were implemented for the pollution control. Changes of capping shapes, sediment contamination, and the time and costs required for the two constructions were compared. Both the pipeline and clamshell technologies were found to satisfy the target thickness of 50 cm on average. However, the pipeline method did not operate sensitively in terms of change of the sea floor topography, resulting in an uneven shape and a thickness. Organic carbon and ignition loss quite decreased after the pipeline or the clamshell capping while pH showed no significant change. Organic and residual fraction of Cd, Ni, and Zn in the sediments appeared to decrease after all cappings. The pipeline method took a construction time four times as much as the clamshell method. The clamshell method was demonstrated to reduce the construction cost by about 40% compared with the pipeline method. However, a monitoring for all the parameters needs to be conducted at least two years in order to better evaluate an efficiency of the pollution control by these capping constructions.