• Journal of the Korean Society of Radiology
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• v.10 no.7
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• pp.503-510
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• 2016

Even though children are exposed to the same amount of radiation, their effective dose amount is higher than those of adults. Therefore, it is very important to reduce the amount of unnecessary radiation exposure because children have a higher radiosensitivity and a smaller body size than adults. In this study, the proposal to seek ways to reduce the amount of radiation is drawn by comparing and analyzing CT Dose Index(CTDI) on the pediatric head CT which was performed at the Busan regional hospitals, to the national diagnostic reference levels. For this, the pediatric head CT scan was conducted among the CT equipments that were installed in downtown Busan. From 2,043 children 10 years old or less who were referred to the pediatric head CT scan, targeting the 28 CT equipments in the 24 hospitals that transmit dose reports to PACS, were examined retrospectively. As a result, the average value of CTDIvol, computed tomography dose index (CTDI) of infant brain, across the hospital, was 31.18 mGy, with DLP of $444.73mGy{\cdot}cm$, which exceeded the diagnostic reference level. The lower the age, the more management is needed for radiation. However, the reality is that the CT examinations are being conducted with a dose that exceeds the reference level as the age of the aged is exceeded. For this purpose, the study seeks to determine the degree of doses of doses outside the diagnostic reference level and analyze the cause of the excess dose and devise measures to reduce the dose reduction.

• International Journal of Automotive Technology
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• v.4 no.2
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• pp.77-86
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• 2003

How to compare the environmental damage caused by vehicles with different foe]s and drive trains\ulcorner This paper describes a methodology to assess the environmental impact of vehicles, using different approaches, and evaluating their benefits and limitations. Rating systems are analysed as tools to compare the environmental impact of vehicles, allowing decision makers to dedicate their financial and non-financial policies and support measures in function of the ecological damage. The paper is based on the "Clean Vehicles" research project, commissioned by the Brussels Capital Region via the BIM-IBGE (Brussels Institute for the Conservation of the Environment) (Van Mierlo et at., 2001). The VriJe Universiteit Brussel (ETEC) and the universite Libre do Bruxelles (CEESE) have jointly carried out the workprogramme. The most important results of this project are illustrated in this paper. First an overview of environmental, economical and technical characteristics of the different alternative fuels and drive trains is given. Afterward the basic principles to identify the environmental impact of cars are described. An outline of the considered emissions and their environmental impact leads to the definition of the calculation method, named Ecoscore. A rather simple and pragmatic approach would be stating that all alternative fuelled vehicles (LPG, CNG, EV, HEV, etc.) can be considered as ′clean′. Another basic approach is considering as ′clean′ all vehicles satisfying a stringent omission regulation like EURO IV or EEV. Such approaches however don′t tell anything about the real environmental damage of the vehicles. In the paper we describe "how should the environmental impact of vehicles be defined\ulcorner", including parameters affecting the emissions of vehicles and their influence on human beings and on the environment and "how could it be defined \ulcorner", taking into account the availability of accurate and reliable data. We take into account different damages (acid rain, photochemical air pollution, global warming. noise, etc.) and their impacts on several receptors like human beings (e.g., cancer, respiratory diseases, etc), ecosystems, or buildings. The presented methodology is based on a kind of Life Cycle Assessment (LCA) in which the contribution of all emissions to a certain damage are considered (e.g. using Exposure-Response damage function). The emissions will include oil extraction, transportation refinery, electricity production, distribution, (Well-to-Wheel approach), as well as the emission due to the production, use and dismantling of the vehicle (Cradle-to-Grave approach). The different damages will be normalized to be able to make a comparison. Hence a reference value (determined by the reference vehicle chosen) will be defined as a target value (the normalized value will thus measure a kind of Distance to Target). The contribution of the different normalized damages to a single value "Ecoscore" will be based on a panel weighting method. Some examples of the calculation of the Ecoscore for different alternative fuels and drive trains will be calculated as an illustration of the methodology.

• Safety and Health at Work
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• v.4 no.3
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• pp.142-148
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• 2013

Background: To elucidate the relationship between seven occupational dermatoses (ODs) and 20 types of work in Greece. Methods: This was a prevalence epidemiologic study of certain ODs among 4,000 workers employed in 20 types of enterprise, in 104 companies, in 2006-2012, using data from company medical records, questionnaires, occupational medical, and special examinations. The ${\chi}^2$ test was applied to reveal statistically significant relationships between types of enterprises and occurrence of ODs. Results: A high percentage (39.9%) of employees included in the study population suffered from ODs. The highest prevalence rates were noted among hairdressers (of contact dermatitis: 30%), cooks (of contact dermatitis: 29.5%), bitumen workers (of acne: 23.5%), car industry workers (of mechanical injury: 15%), construction workers (of contact urticaria: 29.5%), industrial cleaning workers (of chemical burns: 13%), and farmers (of malignant tumors: 5.5%).We observed several statistical significant correlations between ODs (acute and chronic contact dermatitis, urticaria, mechanical injury, acne, burns, skin cancer) and certain types of enterprises. There was no statistically significant correlation between gender and prevalence of ODs, except for dermatoses caused by mechanical injuries afflicting mainly men [${\chi}^2(1)=13.40$, p < 0.001] and for chronic contact dermatitis [${\chi}^2(1)=5.53$, p=0.019] afflicting mainly women. Conclusion: Prevalence of ODs is high in Greece, contrary to all official reports by the Greek National Institute of Health. There is a need to introduce a nationwide voluntary surveillance system for reporting ODs and to enhance skin protection measures at work.

• Journal of agricultural medicine and community health
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• v.40 no.2
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• pp.80-92
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• 2015

Objectives: To clarify the association between dust from large construction sites and allergic and respiratory conditions among residents in Sejong city. Methods: We included 379 individuals older than 50 years from three areas of Sejong city; two areas near construction sites and one area for a comparison. Prevalence of self-reported allergic and respiratory conditions was compared across the three areas using logistic regression to adjust for covariates including age, gender, smoking, and educational attainment. A total of 16 individuals were interviewed to take details of the residents' experiences of construction work. Results: Those living in the nearby areas around construction sites were generally found to have the increased prevalence for all allergic and respiratory conditions. Odds Ratio(OR)s for cough and sneezing among the six symptoms and allergic rhinitis among the three diagnosed diseases reached statistical significance but only OR for cough remained significant after adjustment: adjusted OR for cough was 2.63 (95% CI, 1.07-6.46). Two relevant themes emerged from semi-structured interview were; 1) most residents from the affected area reported a considerable level of exposure to construction dust, 2) about half of them noted that construction dust influences allergic- and respiratory health. Conclusions: General pattern provides suggestive evidence that living close to construction sites may be positively associated with elevated risks of allergic and respiratory conditions. Efforts should be made to establish preventive measures and a comprehensive in-depth health impact assessment on this issue.

• Journal of Environmental Science International
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• v.27 no.2
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• pp.91-97
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• 2018

This study carried out first a component survey on the domestic waste shipped into a waste disposal facility in B city, and then heavy metal analysis of each component according to the SRF standards. Based on this, this study explored the problems with domestic waste and measures to improve them. The results are as follows. The result of the survey of physical components show that paper accounted for the largest proportion with 20.5 %~59.9 %, metals (including batteries) among incombustibles accounted for 0.0~8.3 %, other inorganic substances, glass and ceramics accounted for 0.0~43.7 % and 0.0 %~19.6 % respectively. However, the proportion of coated viny and plastics, which have high lead and cadmium content, was rather high with 2.9 %~30.9 %. This suggests the possibility that actual concentration of lead and cadmium within SRF is likely to be higher. Among the 15 components contained in the waste brought into the waste disposal facility, 10 components (food waste, textiles, vinyl, plastics, wood, rubber and leather, paper, metals, electronic substrates, and nail polish) were analyzed according to assay samples (approximately 0.1 g and 0.3 g). The result of analysis shows that the amount of Cd and Pb detected in coated vinyl for 0.109 g of assay sample was 98.6 mg/kg and 20.6 mg/kg respectively; 117.0 mg/kg and 29.0 mg/kg respectively for 0.313 g of assay sample. This is high contents exceeding the Cd standard. As for wooden component, the amount of Pb was 480.0 mg/kg for 0.3 g of assay sample. This suggests that there always exists the possibility of exceeding the exposure level of heavy metals (Cd and Pb) in SRF as long as coated wood and vinyl plastics with high contents of Pb and Cd are shipped into the waste disposal facility; and the local government and the residents need to work hard to improve the situation including development of the machine to sort electronic substrates and batteries for separate collection of the waste of coated vinyl and plastics within domestic waste.

• Tuberculosis and Respiratory Diseases
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• v.47 no.6
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• pp.817-823
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• 1999

Background: The prevalence of allergic disease has increased substantially over the past decades. The reasons for these trends are complex but include increased environmental allergen exposure. Environmental control measures are of particular importance in the prevention and management of allergic disease. Thus, we purposed to evaluate the changes of causative allergens in allergic patients in Chonbuk provincial area that began industralized recently. Method: To evaluate the allergens epidemiologically, we performed skin prick tests and RAST in 201 allergic patients from February, 1984 to February, 1985 and 339 patients from February, 1997 to February, 1998. Results: The Following results were obtained. 1) Total sensitization rates did not change significantly(74.2% vs 75.8%, p=0.664). 2) Positive reaction rates to pollens were similar(35.8% vs 30.1%, p=0.17). 3) Positive rates to HDM(house dust mite) were decreased(66.1% vs 56.3%, p=0.02). 4) Positive rates to fungi and animal danders were decreased significantly(p<0.001). Conclusion : Environmental allergens associated with hygine in Chonbuk provincial areas such as HDM and fungi are decreased significantly during 13 years.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.22 no.3
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• pp.175-183
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• 2012

Objectives: This study developed a harmonized method for risk assessment based on the Hazard & Risk Evaluation of Chemicals (HREC) according to the Industrial Safety and Health Act (ISHA). Methods: Three preliminary studies, performed during 2010 and 2011 by the Occupational Safety and Health Research Institute and three academic research groups, were compared. The differences in risk assessment, especially in the dose-response assessment method, were analyzed. A new harmonized method for dose-response assessment was suggested and its applicability for the HREC was examined. Results: Considering the various steps of each dose-response assessment, the equivalent steps in quantitative correction, uncertainty factor 2 (UF2) for intra-species uncertainty, and UF3 for the experimental period in the uncertainty correction were relatively high. Using our new method, the total correction values (quantitative correction plus uncertainty correction) ranged from 72~15,789 to 30~60, and the ratio of the threshold limit value (TLV) to the reference concentration decreased from 12.8~1900 to 5.4~11.8. Furthermore, when we performed risk characterization by our new method, hazard quotient (HQ) values for chloroethylene, epichlorohydrin, and barium sulfate became 3.0, 14.1, and 1.13 respectively, whereas three previous studies reported HQ values of 7.1, 4580, and 87.3 considering reasonable maximum exposure (RME) conditions. HQs of the three chemicals were calculated to be 0.6, 2.4, and 0.1 respectively, when compared to their TLVs. Conclusions: Our new method could be applicable for the HREC because the total correction values and the ratio of TLVs were within reasonable ranges. It is also recommended that additional risk management measures be applied for epichlorohydrin, for which the HQ values were greater than 1 when compared with both reference values and the TLV. Our proposed method could be used to harmonize dose-response assessment methods for the implementation of risk assessment based on the HREC according to ISHA.

• Journal of Preventive Medicine and Public Health
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• v.40 no.2
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• pp.155-161
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• 2007

Objectives : Bisphenol A diglycidyl ether (BADGE) is the major component in commercial liquid epoxy resins, which are manufactured by co-reacting bisphenol A with epichlorohydrin. This study was performed to show the developmental effects of prenatal and postnatal exposures to BADGE in male rat offspring. Methods : Mated female rats were divided into four groups, each containing 12 rats. The dosing solutions were prepared by thoroughly mixing BADGE in corn oil at the 0, 375, 1500 and 3000 mg/kg/day concentrations. Mated females were dosed once daily by oral gavage on gestation day (GD) 6 - 20 and postnatal day (PND) 0 - 21. Pregnant female dams were observed general symptoms and body weight. Also, male pups were observed the general symptoms, body weight, developmental parameters (e.g. anogenital distance, pina detachment, incisor eruption, nipple retention, eye opening, testis descent), organ pathologic changes and hormone levels of plasma. Results : Pregnant rats treated with BADGE died at a rate of about 70% in the 1500 mg/kg/day group and all rats treated with 3000 mg/kg/day died. Body weight, for male pups treated with doses of 375 mg/kg/day, was significantly lower than in the control group at PND 42, 56, and 63 (p<0.05). Evaluation of body characteristics including; separation of auricle, eruption of incisor, separation of eyelid, nipple retention, descent of testis, and separation of the prepuce in the BADGE treated group showed no difference in comparisons with the control group. AGD and adjusted AGD (mm/kg) for general developmental items in BADGE 375 mg/kg/day treated pups tended to be longer than in controls, however, these differences were not statistically significant. Relative weights of adrenal gland, lung (p<0.05), brain, epididymis, prostate, and testis (p<0.01) were heavier than in control in measures at PND 9 weeks. There were no significant changes in comparisons of histological findings of these organs. Loss of spermatids was observed in the seminiferous tubule at PND 9 weeks, but no weight changes were observed. The plasma estrogen levels were similar in the control and treatment groups at PND 3, 6 and 9 weeks. The plasma testosterone levels in the control group tended to increase with age. However, in the BADGE 375 mg/kg/day treated male pups it did not tend to increase. Conclusions : These findings suggest that BADGE is a chemical that has developmental effects consistent with it being an endocrine disruptor.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.11
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• pp.1776-1788
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• 2019

Objective: The demands for measures to improve disease resistance and productivity of livestock are increasing, as most countries prohibit the addition of antibiotics to feed. This study therefore aimed to uncover functional feed additives to help enhance livestock immunity and disease resistance, using Acanthopanax sessiliflorus fruit extract (ASF). Methods: ASF was extracted with 70% EtOH, and total polyphenolic and catechin contents were measured by the Folin-Ciocalteu and vanillin assay, respectively. The 3D4/31 porcine macrophage cells ($M{\Phi}$) were activated by phorbol 12-myristate 13-acetate (PMA), and cell survival and growth rate were measured with or without ASF treatment. Flow-cytometric analysis determined the lysosomal activity, reactive oxygen species levels (ROS), and cell cycle distribution. Nuclear factor kappa B ($NF-{\kappa}B$) and superoxide dismutase (SOD) protein expression levels were quantified by western blotting and densitometry analysis. Quantitative polymerase chain reaction was applied to measure the lipid metabolism-related genes expression level. Lastly, the antibacterial activity of 3D4/31 $M{\Phi}$ cells was evaluated by the colony forming unit assay. Results: ASF upregulated the cell viability and growth rate of 3D4/31 $M{\Phi}$, with or without PMA activation. Moreover, lysosomal activity and intracellular ROS levels were increased after ASF exposure. In addition, the antioxidant enzyme SOD2 expression levels were proportionately increased with ROS levels. Both ASF and PMA treatment resulted in upregulation of $NF-{\kappa}B$ protein, tumor necrosis factor $(TNF){\alpha}$ mRNA expression levels, lipid synthesis, and fatty acid oxidation metabolism. Interestingly, co-treatment of ASF with PMA resulted in recovery of $NF-{\kappa}B$, $TNF{\alpha}$, and lipid metabolism levels. Finally, ASF pretreatment enhanced the in vitro bactericidal activity of 3D4/31 $M{\Phi}$ against Escherichia coli. Conclusion: This study provides a novel insight into the regulation of $NF-{\kappa}B$ activity and lipid metabolism in $M{\Phi}$, and we anticipate that ASF has the potential to be effective as a feed additive to enhance livestock immunity.

• Korean Journal of Soil Science and Fertilizer
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• v.20 no.2
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• pp.139-145
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• 1987

This study was carried out to find out the effects of ammonia gas on the leaf destruction of vegetable crops, and nitrogen contents in their leaves. Radish, chinese cabbage, tomato and cucumber were fumigated with 0.05, 0.1, $0.2mg/{\ell}$ ammonia gas for 2 hrs under different exposure time, light and soil water condition at vegetative growth stage. The results obtained were as follows. The crop damages measured by percentage of leaf destruction were more severe at the night time fumigation than treatment during the day, at the full sun condition than the shading, and at the higher soil water contents. Cucumber plant showed higher resistance to ammonia gas than tomato plant. The chrolophyll contents in leaves of each crops were remarkably decreased by increment of ammonia concentration from $0.05mg/{\ell}$ to $0.2mg/{\ell}$, but the N content in them was increased.