• Journal of Environmental Science International
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• v.26 no.10
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• pp.1185-1200
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• 2017

Solid waste management is currently a topic of concern, particularly in the protection of humans and the environment from toxic pollutants and hazardous materials. The importance of solid waste management is recognized at international, national, and community levels. Different agendas have been prioritized and assigned to improve quality of life, productivity, and health, and reduce the burden of pollution. Suitable management of solid waste requires appropriate technology that is affordable, socially accepted, and environmentally friendly. The use of a smart management system involving system dynamics can save energy, money, and labor. System dynamics is a computer-based approach that aids in predicting the behavioral patterns of variables, and correlating dependent and independent variables. The inclusion of system dynamics-based models in solid waste management has recently become more common. In this review, we used system dynamics to determine methods to disentangle solid waste management systems and analyzed different studies on solid waste management using system dynamics in different countries in detail. We also discussed the various software packages that are available for system dynamics and their usefulness for waste management. This review may help in understanding current solid waste management practices using system dynamics.

• Korean Journal of Agricultural Science
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• v.28 no.1
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• pp.48-58
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• 2001

This study was conducted to investigate the effects of environmental sound rice farming method on the productivity of rice industry which may result in impacts on the staple food securities. Recently fanners have been concerned about adopting new rice cultivation method such as organic and low input farming system in which fertilizer and pesticide can be substantially reduced so as to alleviate the burden of agro-ecosystem. However, It has been argued about whether or not there are negative impacts on the self sufficiency rate of food, income of farm household and technological adaptability. Therefore this study examined the productivity trend of environmental rice farming system and predicted the long term rice self-sufficiency rate when environmental rice farming system are adopted by assuming various scenarios. It was estimated that rice self-sufficiency rate can be decreased up to 52.2% by 2010. Based on the analysis of results, policy recommendations for environmentally sound rice farming were suggested as follows: 1) gradual adopting and transferring of environmental rice cultivation method, 2) increasing profitability of rice growing fanners 3) developing the farm level technology specific to Korean farming condition, 4) institutionalization of direct payments for encouraging environmental rice fanning.

• Journal of Microbiology and Biotechnology
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• v.29 no.10
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• pp.1629-1635
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• 2019

Azo dyes are recalcitrant pollutants, which are toxic, carcinogenic, mutagenic and teratogenic, that constitute a significant burden to the environment. The decolorization and the mineralization efficiency of Remazol Brillant Orange 3R (RBO 3R) was studied using a probiotic consortium (Lactobacillus acidophilus and Lactobacillus plantarum). Biodegradation of RBO 3R (750 ppm) was investigated under shaking condition in Mineral Salt Medium (MSM) solution at pH 11.5 and temperature $25^{\circ}C$. The bio-decolorization process was further confirmed by FTIR and UV-Vis analysis. Under optimal conditions, the bacterial consortium was able to decolorize the dye completely (>99%) within 12 h. The color removal was 99.37% at 750 ppm. Muliplex PCR technique was used to detect the Lactobacillus genes. Using phytotoxicity, cytotoxicity, mutagenicity and biototoxicity endpoints, toxicological studies of RBO 3R before and after biodegradation were examined. A toxicity assay signaled that biodegradation led to detoxification of RBO 3R dye.

• Toxicological Research
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• v.17
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• pp.25-35
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• 2001

In 1990, Tolerable Daily Intake (TDI) of 10 pg TCDD/kg/day for dioxins based on carcinogenicity and reproductive toxicity was determined by WHO/EURO, that resulted in the establishment of TDIs in other countries. In Japan, Ministry of Health and Welfare and Environment Agency, respectively established the TDI of 10 pg TCDD/kg/day and Health Risk Assessment Index of 5 pg TCDD/kg/day in 1996. Accumulation of new scientific data, especially by molecular toxicology since 1990, resulted in the reevaluation of TDI by WHO-ECEH and IPCS in May, 1998. At this meeting, it was stressed that \circled1 toxic effects of dioxin is mediated through Ah-receptor in both animals and humans, \circled2 use of ebody burdeni concept is better than the use of traditional NOAEL/UF approach, \circled3 inclusion of coplanar PCBs in the TDI by the use of new WHO-TEF. LOAELs (0.16~200 ng TCDD/kg/day) obtained from reproductive toxicity and immunotoxicity in rats, and neurobehavioral toxicity and induction of endometriosis in rhesus monkeys are calculated to be the body burden of 10~50 ng TCDD/kg that is 14~37 pg TEQ/kg/day as human daily intake. Finally TDI of 1~4 pg TEQ/kg/day was established by applying the UF of 10. In Japan, reproductive toxicity and immunotoxicity in rats were used to obtain LOAELs (100~200 ng TCDD/kg/day). Finally TDI of 4 pg TEQ/kg/day was established in June 1999 by applying the UF of 10 to human daily intake of 43.6 pg TEQ/kg/day which corresponds to the body burden of 86 ng TCDD/kg.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.27 no.4
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• pp.371-379
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• 2017

Objectives: The purpose of this study is to investigate the differences and the influencing factors of health habits such as smoking, drinking, and exercise on job stress among IT workers. Methods: A questionnaire was distributed to total of 300 people (30 persons per business place) at 10 IT work sites performing computer and information system tasks, and 275 data points were analyzed. The survey items were general characteristics, occupational characteristics, employment type, physical burden, amount of drinking, smoking, exercise, and job stress. Results: The results of this study are summarized as follows. First, non-regular workers showed higher smoking, exercise, and job stress than did regular workers by employment type, but exercise was not significant. Regular workers had a higher rate of drinking than non-regular workers. Second, the factors affecting alcohol drinking were gender and age, and factors affecting smoking were gender and employment type. Third, factors affecting job stress were annual income, long working hours, physical burden, and employment type. Conclusions: It is necessary to consider employment patterns in smoking, drinking, and job stress management. In addition, it is necessary to deeply analyze what affects the health behaviors and job stress of IT workers and explore ways to mitigate them.

• Environmental Analysis Health and Toxicology
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• v.17 no.2
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• pp.109-115
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• 2002

This study was conducted to investigate the reference value of mercury (Hg) in liver and kidney of Korean population. The mercury concentration in 244‘sudden and unexpected death’autopsies (male: 180, female: 64) aged from 0 to 87 years was analyzed. The concentration of mercury was measured by atomic absorption spectrophotometer (Perkin-Elmer Model 5100) with mercury/hydride generating system (FIAS 400). The contents of mercury in liver and kidney fitted well the log-normal distribution rather than normal distribution. Geometric mean concentration of mercury in liver and kidney was 0.115 $\mu\textrm{g}$/g wet weight and 0.149 $\mu\textrm{g}$/g wet weight, respectively. Geometric mean concentration of mercury in female was higher than in male (p < 0.01). The mercury content in liver and kidney increased with age up to the forties and slightly decreased there-after. The regression model of mercury deposit in liver and kidney by age was predicted as the following equation : Log LHg : -1.0576＋0.0045$.$Age-0.0001$.$Age$^2$＋0.0873$.$Sex, Log KHg = -1.0576＋0.0152$.$Age-0.0002$.$Age$^2$＋0.1935$.$Sex. The liver burden of mercury was estimated to be 158.3∼161.3 $\mu\textrm{g}$ in male and 163.0∼166.9 $\mu\textrm{g}$ in female. The kidney burden of mercury was estimated to be 42.0∼42.9 $\mu\textrm{g}$ in male and 55.5∼57.1 $\mu\textrm{g}$ in female.

• Environmental Analysis Health and Toxicology
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• v.19 no.2
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• pp.191-200
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• 2004

Zinc (Zn) is an essential element in biological process, however inadequate Zn status in general population have been recognized. To update the knowledge for Zn-cadmium (Cd) interaction, we studied the intestinal uptake and transport, and the expression of metal transporter proteins (divalent metal transporter 1, DMT1 ; metal transporter protein 1, MTP1 ; zinc transporter 1, ZnTl ; metallothionein 1 , MT1) in duodenum after Cd exposure using Zn deficient animal model. Rats were led Zn deficient (ZnD, 0.5-1.0 mgZn/kg) or Zn supplemented (ZnS, 50mg Zn/kg) diet for 4 weeks, and followed single administration of $^{109}$ CdCl$_2$orally. The body Zn flatus and tissue Cd concentration were determined at 24 hrs after Cd administration. Total body burden of Cd and Cd absorption index (AI, %) were estimated based on the tissue Cd analyzed. DMT1, MTP1, ZnTl and MT1 mRNA were analyzed by using RT-PCR method. Feeding of Zn deficient diet for 4 weeks produced a reduced body weight gain and a depletion of body Zn. Tissue Cd concentration, body burden of Cd and Cd absorption index were higher in the ZnD diet fed rats than the ZnS diet red rats. Especially, Cd concentration in the small intestine (duodenum, jejunum and ileum) and the colon of FeD diet fed rats were higher markedly than in the FeS diet group. The expression levels of DMT1, MTP1 and ZnT1 mRNA in FeD diet fed rats were similar to the FeS diet. The level of MT1 mRNA expression was significantly lower in the FeD than the FeS diet fed rats. Taken together, theses results indicate that Zn deficiency in diet induce an increased intestinal absorption and tissue retention of Cd, and down -regulate the MT1 expression in the intestine which might be play a part of role in Cd absorption and transport in mammalian. These findings suggest that deficiency of essential metal could be enhanced the toxicity of toxic, non-esstial metals through the metal-metal interaction.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.9
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• pp.4421-4426
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• 2016

Background: Smoking is recognized as a main leading preventable cause of mortality and morbidity worldwide. It is responsible for a considerable financial burden both on the health system and in society. This study aimed to examine the effect of smoking on cost of hospitalization and length of stay (LoS) among patients with lung cancer in Iran in 2014. Materials and Methods: A total of 415 patients were included in the study. Data on age, sex, insurance status, type of hospitals, type of insurance, geographic local, length of stay and cost of hospitalization was extracted by medical records and smoking status was obtained from a telephone survey. To compare cost of hospitalization and LoS for different smoking groups, current smokers, former smokers, and never smokers, a gamma regression model and zero-truncated poisson regression were used, respectively. Results: Compared with never smokers, current and former smokers showed a 48% and 35% increase in hospitalization costs, respectively. Also, hospital LoS for current and former smokers was 72% and 31% higher than for never smokers, respectively. Conclusions: Our study indicated that cigarette smoking imposes a significant financial burden on hospitals in Iran. It is, however, recommended that more research should be done to implement and evaluate hospital based smoking cessation interventions to better increase cessation rates in these settings.

• Journal of environmental and Sanitary engineering
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• v.21 no.2 s.60
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• pp.57-68
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• 2006

This study was designed to provide basic data on preventive plans by affecting factors that have analysed on musculoskeletal diseases. The survey were conducted from July 1 to 30, 2004 among 600 hair dressers working in Seoul and Gwangju using self-administration questionnaire. The results of this study are summarized as follows: The pain experience rate of musculoskeletal diseases. in the last one yea was 55.2%. 35.7% of respondents answered they had pain on shoulders, 30.6% had pain on legs and feet, 28.9% had pain on waist, 26.8% had hands, fingers and wrist, 22.3% had pain on necks and 17.6% had pain arms and elbows more than disease on necks, shoulders, arms and elbows, hands, fingers and wrists, waist, shoulders legs and feet. The prevalence rate of the last week was 40.3%. The prevalence rate in each body parts of the last week was 23.3% on legs and feet, 21.2% on shoulders, 20.8% on waist, 14.9% on hands, fingers and wrists, 14.4% on necks, 9.3% on arms. The affecting factors on musculoskeletal disease index were analysed by multiple linear regression analysis. there are working posture$(\beta=0.27)$; authority of task$(\beta=0.18)$, self-conscious stress $(\beta=0.16)$, age$(\beta=0.14)$, physical burden from work$(\beta=0.13)$, and task required$(\beta=0.10)$. Determinant coefficients was 22.7%. Based on the results above, working posture, job stress and physical burden from task are highly related with pain. In order to prevent musculoskeletal disease of hairdressers, working posture shall be improved and leisure opportunities to relieve stress, and health management education shall be provided.

• 기술발표회
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• s.2006
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• pp.279-291
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• 2006

This study shows decision-making process for selection of cutoff wall on a wastewater treatment project. There are 10 different cut-off wall methods So, we examine the site to gather information for find appropriate methods. After using that information, 10 cutoff wall methods are reviewed for analysis. Through brainstorming, four alternatives are selected for design VE item. Following the standard VE process, we established performance criteria and evaluated function score(F) using questionnaire. The questionnaires, brainstorming and AHP method for weighting on performance criteria and evaluate function score increased the reliability of this selection process. Water Jet method, one of four methods, has the best function score(F=92.71) and the lease construction cost(as cost index 1,000). The value score also highest as 92.7, so we select the method. The result is value innovation type In addition, the authors try to calculate the environmental burden in selection process using LCA. We cannot conduct the full LCA as defined ISO, so perform Simple LCA In LCA result, the cut-off grouting has the least environmental burden as index 9.09E+01 and Water Jet method has following as the second. To selection best method to specific area and purpose, design VE/LCG process used as useful tool and it is needed to develop integrated method that evaluate VEILCC and LCA as one-set process.