• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.7 no.2
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• pp.289-297
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• 1997

Work-related low back pain(below LBP) is one of the major cause of morbidity, disability, limitation of activity and economic loss. Therefore the work-related LBP is one of the major issue in the field of industrial safety and health. This study was performed for detecting the risk factors and proposing the effective control programs of work-related LBP. The subjects were male workers employed at the welding and metal factory. The data was collected by self-reported questionnaire, interview and checking abdomen muscular and grasping power for two days on October, 1993. The contents of questionnaire were as follow: the experience of LBP, general characteristics, physical characteristics, employment status, type of work and working environment. The number of cases was 104 with a history of work-related LBP, so the prevalence of work-related LBP was 35.0%, and the number of controls was 140 without any history of LBP. As a result, marital status, educational level, abdomen muscular power, tenure, category of job, satisfaction of job, working posture, satisfaction for table and chair and lifting materials showed a statistical significance between the case and control groups. 284 Lifting jobs were quantified by NIOSH lifting equation method and ergonomic computer modelling methods. There were no significant differences in the action limit and disc compression force between group with LBP and without LBP. But in the lifting frequency and cumulative disc compression force there were significant differences. Therefore work-related LBP should be prevented by the ergonomic and environmental control.

• Journal of Environmental Science International
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• v.20 no.12
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• pp.1509-1519
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• 2011

The protective effect of nitric oxide (NO) on the antioxidant system under paraquat(PQ) stress was investigated in leaves of 8-week-old lettuce (Lactuca sativa L.) plants. PQ stress caused a decrease of leaf growth including leaf length, width and weight. Application of NO donor, sodium nitroprusside (SNP), significantly alleviated PQ stress induced growth suppression. SNP permitted the survival of more green leaf tissue preventing chlorophyll content reduction and of higher quantum yield for photosystem II than in non-treated controls under PQ exposure, suggesting that NO has protective effect on chloroplast membrane in lettuce leaves. Flavonoids and anthocyanin were significantly accumulated in the leaves upon PQ exposure. However, the rapid increase of these compounds was alleviated in the SNP treated leaves. PQ treatment resulted in lipid peroxidation and induced accumulation of hydrogen peroxide ($H_2O_2$) in the leaves, while SNP prevented PQ induced increase in malondialdehyde (MDA) and $H_2O_2$. These results demonstrate that SNP serves as an antioxidant agent able to scavenge $H_2O_2$ to protect plant cells from oxidative damage. The activities of two antioxidant enzymes that scavenge reactive oxygen species, superoxide dismutase (SOD) and catalase (CAT) in lettuce leaves in the presence of NO donor under PQ stress were higher than those under PQ stress alone. Application of 2-(4-carboxyphenyl)-4, 4, 5, 5-tetramethylimidazoline-1-oxyl-3-oxide (PTIO), a specific NO scavenger, to the lettuce leaves arrested SNP mediated protective effect on leaf growth, photosynthetic pigment and antioxidant systems. However, PTIO had little effect on lettuce leaves under PQ stress compared with that of PQ stress alone. The obtained data suggest that the damage caused by PQ stress is in part due to increased generation of active oxygen by maintaining increased antioxidant enzyme activities and SNP protects plants from oxidative stress. From these results it is suggested that NO might act as a signal in activating active oxygen scavenging system that protects plants from oxidative damage induced by PQ stress and thus confer PQ tolerance.

• Journal of Environmental Health Sciences
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• v.38 no.4
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• pp.300-310
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• 2012

Objectives: Indoor air quality problems in public spaces have recently become a very important issue in South Korea, because many spend a long time every day indoors. In this study, an extensive literature review was performed on the subject of suspended bacteria and fungi in public facilities. The objective of this study was to evaluate the extent and types of suspended bacteria and fungi in indoor air in South Korea. This study will provide direction to the research in the field of indoor air. Methods: Article reviews was conducted using a search engine and the following keywords; 'bacteria', 'total suspended bacteria', 'fungi' and 'indoor air' from published articles since 2000. Results: Most of the places of measurement were schools, kindergartens, childcare centers and general hospitals. The highest concentrations of total suspended bacteria and fungi were found in schools and kindergartens. Some public facilities exceeded the standard of 800 CFU/$m^3$. There were few studies on other suspended bacteria: Gram Negative Bacteria, Staphylococcus and Klebsiella pneumoniae. Conclusions: It appears that more studies with intensive controls are needed. It was found that schools and kindergartens were most susceptible to microbial indoor air pollution. These results may be able to suggest an indoor standard for suspended bacteria and fungi in South Korea.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6591-6593
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• 2013

Background: Environmental tobacco smoking (ETS) significantly contributes to morbidity and mortality and is a known risk factor for lung cancer development in lifelong nonsmokers. The metabolite 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) and its glucuronides (NNAL-Glucs) have now emerged as leading biomarkers for the study of carcinogen exposure in non-smokers exposed to ETS. Materials and Methods: We carried out our study on NNAL in the urine of non-smokers exposed to ETS and the association between ETS and lung cancer. Subjects were enrolled from 2008-2010. NNAL was analyzed for 74 non-smoking lung cancer and 85 healthy controls. The main objective of this study was to provide an estimate of the risk of lung cancer from exposure to ETS in the Korean population. Results: The mean NNAL concentration in urine was significantly lower in non-smoking patient groups (n=74) than in control groups (n=85) ($4.7{\pm}15.0$ pg/mg, $6.5{\pm}17.9$ pg/mg, respectively, Mann-Whitney U test, p<0.001). Conclusions: The urine NNAL of non-smoking patients with lung cancer was not elevated with regard to the non-smoking control group. This may be due to life-style changes after diagnosis. A prospective study will be needed to evaluate the association of NNAL and non-smoking lung cancer.

• Korean Journal of Environmental Agriculture
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• v.33 no.2
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• pp.144-147
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• 2014

BACKGROUND: It is essential to prioritize the exact and clear understanding of agricultural nonpoint source pollution (NPS) controls. The realistic policies and systems should also be developed based on this understanding. Therefore, this study aimed to present agricultural Best Management Practices (BMPs) applicable for the fields based on the Delphi survey result. METHODS AND RESULTS: This study deduced the evaluation items to assess each BMP for agricultural NPS control and conducted the surveying using the Delphi method based on agricultural BMP experts. In addition, its on-the-spot application were evaluated. Considering its importance, technical, social and economic proprieties showed that political support was ranked first and followed by cost investment, labor investment, reduction effect and resident participation. The survey findings by agricultural BMP experts showed the good performance of on-the-spot application can be achieved from fertilization by soil testing, residue and green manure application and contour plowing which are applicable within a field. Agricultural BMPs, highly applicable for the fields, were the countermeasures that farmers who are the principal bodies of agricultural NPS control could be participated directly. CONCLUSION: The active participation of farmers is essential for effective control of agricultural NPS. It is necessary to establish various incentive systems.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.4 no.1
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• pp.81-95
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• 1994

This study was performed in a diatomite factory where silicosis had been found at October, 1993. The major objectives were to evaluate worker exposure to diatomaceous earth and to present engineering control methods for workplace management. Total and respirable dust of diatomaceous earth were measured. Size distribution of dust was analyzed by applying the multiple diffraction method. Also crystalline silica in respirable dust samples was analyzed qualitatively by X-ray diffraction. The suitable Local Exhaust Ventilation systems for that factory were recommended. The results were as follows. The airborne total and respirable dust concentrations by exposure groups showed approximate normal distribution. The means of total dust exposures at flour maufacturing, fire brick grinding and packaging, ceramic raws packaging processes exceeded Korean and ACGIH standards, $10mg/m^3$. The means of total and respirable dust concentrations to high exposure groups were 6.8 and 3.9 times higher than those of low expousre groups, respectively. The size distribution of diatomaceous earth dust was lognormal with a median diameter of $7.07{\mu}m$(range, $0.10-60.0{\mu}m$) and with a geometric standard deviation of 1.43. The crystalline silica in respirable dust samples was identified to quartz and cristobalite and/or tridymite. Above results suggest that engineering controls and periodic environmental and medical surveillances will be important for preventing silicosis in the diatomite factory.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.7
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• pp.3329-3334
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• 2012

Background: Several potential risk factors have been identified for diffuse large B-cell lymphoma (DLBCL); however, epidemiological studies investigating the association between these risk factors and DLBCL have yielded inconsistent results. Objectives: To investigate potential medical, lifestyle, and environmental risk factors of DLBCL in Shanghai, China through a hospital-based case-control study. Method: One-hundred-and-forty-seven newly diagnosed DLBCL patients and 294 sex- and age-matched controls were recruited from 11 hospitals in Shanghai between 2003 and 2007. A standardized structured questionnaire was used to obtain patient data on demographics, medical history, family history, lifestyle, and environmental exposures. Conditional logistic regression models were used to estimate odds ratios (ORs), with 95% confidence intervals (CIs), for risk associated with each data category. Results: History of tuberculosis (TB) infection and "living on a farm" were positively associated with DLBCL (TB: OR=3.05, 95% CI: 1.19-7.80; farm: OR=1.82, 95% CI: 1.21-2.73). In contrast, taking traditional Chinese medicine was negatively associated with DLBCL (OR=0.36, 95% CI: 0.14-0.89). No significant correlation with DLBCL risk was found for any of the other potential risk factors (p>0.05), including but not limited to hair dyes, alcohol drinking, smoking, and home/workplace renovation within one year. Conclusions: Consistent with results from previous studies in other DLBCL case populations, traditional Chinese medicine appeared to have a direct or indirect protective effect against DLBCL. However, this study also identified a possible predisposition for DLBCL in TB sufferers and farmers.

• Economic and Environmental Geology
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• v.3 no.4
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• pp.199-222
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• 1970

One of the biggest sulfide metallic (Cu, Pb, Zn) ore deposits of South Korea is located in the area of Seo-myeon, Shiheung-gun, Gyeonggi-do. Geology of the region is mostly composed of metasediments of biotite schist, graphite schist, injection gneiss, sericite schist, limesilicate and quartzite from bottom, those are applicable to so-called Yeoncheon System of Pre-Cambrian, and granodiorite, quartz porphyry, basic dykes are outcroped in a small scope as intrusives. The origin of the ore deposit is pyrometasomatic contact deposits due to hydrothermal replacement and the ore bodies are imbedded in lower bed of limesilicate formation as impregnation and ore minerals are galena, sphalerite, marmatite, chalcopyrite, bornite, chalcocite, covellite, and the later two minerals are both hypogene and supergene. Gangue minerals are mostly skarn minerals those hornblende, diopside, epidote, hedenbergite, chlorite, garnet and quartz except primary calcite and quartz. Boundary plane (NS strike) between schists and limesilicate seemed to be primary opening of ore solution and fractures bearing $N50^{\circ}{\sim}80^{\circ}W$ are secondary structural control for localization of ore minerals and the third structural controls are both irregular gashes and schistosity in small scale. Photogeological study was carried with vertical aerial photo scaled 1: 38,000 and enlarged 1 : 10,000 under stereoscope. The study on the area convinced the fact that the geologic boundaries between rocks, limesilicates and quartzites, are traced easily by their typical topographic feature and drainage, and the main fracture patterns which derived from the result of fracture traces, that photogeologic lineament observed under stereoscope, are those bearing (1) $N20^{\circ}W$, (2) $N58^{\circ}W$, (3) $N76^{\circ}W$, (4) EW, (5) $N20^{\circ}W$, (6) $N62^{\circ}W$, (7) $N77^{\circ}W$. Among the written fractures, (5) (not schistosity, in case of fault) (6) (7) are post-mineral faults and others are pre-mineral faults and others are pre-mineral structures, and (2) (3) (6) (7) are coincided with statistical figure of 208 fractures surveyed in underground. By the result of the study, mineralized zone, are presumed to extend north and southward, total length about 4km.

• Journal of Korean Society for Atmospheric Environment
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• v.24 no.E1
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• pp.1-11
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• 2008

Mercury (Hg), which is mainly emitted from coal-fired power plants, remains one of the most toxic compounds to both humans and ecosystems. Hg pollution is not a local or regional issue, but a global issue. Hg compounds emitted from anthropogenic sources such as coal-fired power plants, incinerators, and boilers, can be transported over long distances. Since the last decade, many European countries, Canada, and especially the United States, have focused on technology to control Hg emissions. Korea has also recently showed an interest in managing Hg pollution from various combustion sources. Previous studies indicate that coal-fired power plants are one of the major sources of Hg in Korea. However, lack of Hg emission data and feasible emission controls have been major obstacles in Hg study. In order to achieve effective Hg control, understanding the characteristics of current Hg sampling methods and control technologies is essential. There is no one proven technology that fits all Hg emission sources, because Hg emission and control efficiency depend on fuel type, configuration of air pollution control devices, flue gas composition, among others. Therefore, a broad knowledge of Hg sampling and control technologies is necessary to select the most suitable method for each Hg-emitting source. In this paper, various Hg sampling methods, including wet chemistry, dry sorbents trap, field, and laboratory demonstrated control technologies, and international regulations, are introduced, with a focus on coal-fired power plants.

• Korean Journal of Environmental Agriculture
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• v.35 no.4
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• pp.256-262
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• 2016

BACKGROUND: 'Shiranuhi' mandarin is one of the popular citrus cultivars in Jeju Island, Korea. However, the emergence of scion roots since the past few years has altered its flowering, fruiting, and quality. Girdling of branches is one of the methods of increasing flowering in citrus trees. METHODS AND RESULTS: This experiment was conducted to determine the effect of girdling on the flowering and yields of scion rooted 'Shiranuhi' mandarin hybrid. We selected normal trees without scion roots as controls. The trees with scion roots were divided into two groups: trees without girdling and with girdling on main branches. Each group contained five replications and the experiment was conducted in Gosan and Harye of Jeju Island. The scion rooted trees revealed severely decreased flowering and low flowering/leaf ratios; however, the leaf/fruit ratio significantly increased. But, girdling on main branches significantly increased flowering and the flowering/leaf ratio. In the scion rooted trees, yields dropped due to poor flowering; however, girdling of branches efficiently improved the yields of the trees. Fruit quality, fruit size, and fruit weight of scion rooted trees were low in comparison with the control, whereas girdling of the branches improved flowering and the fruit weight to some extent. No significant difference in soluble solid contents was observed. CONCLUSION: Girdling is an effective method to induce flowering of the scion rooted 'Shiranuhi' mandarin trees. In addition, yields of scion rooted trees were improved.