• Economic and Environmental Geology
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• v.54 no.6
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• pp.743-752
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• 2021

The three-dimensional distribution of the fault was evaluated using gravity field interpretation such as curvature analysis and Euler deconvolution in the Seoul-Gyeonggi region where the Chugaryeong fault zone was developed. In addition, earthquakes that occurred after 2000 and the location of faults were compared. In Bouguer anomaly of Chugaryeong faults, the Pocheon Fault is an approximately 100 km fault that is extended from the northern part of Gyeonggi Province to the west coast through the central part of Seoul. Considering the frequency of epicenters is high, there is a possibility of an active fault. The Wangsukcheon Fault is divided into the northeast and southwest parts of Seoul, but it shows that the fault is connected underground in the bouguer anomaly. The magnitude 3.0 earthquake that occurred in Siheung city in 2010 occurred in an anticipated fault (aF) that developed in the north-south direction. In the western region of the Dongducheon Fault (≒5,500 m), the density boundary of the rock mass is deeper than that in the eastern region (≒4,000 m), suggesting that the tectonic movements of the western and eastern regions of the Dongducheon Fault is different. The maximum depth of the fracture zone developed in the Dongducheon Fault is about 6,500 m, and it is the deepest in the research area. It is estimated that the fracture zone extends to a depth of about 6,000 m for the Pocheon Fault, about 5,000 m for the Wangsukcheon Fault, and about 6,000 m for the Gyeonggang Fault.

• Korean Journal of Environmental Agriculture
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• v.41 no.2
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• pp.108-114
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• 2022

BACKGROUND: This study was performed to determine residual characteristics of soil-treated metalaxyl-M and dinotefuran in crown daisy and to evaluate the risks from intake of the residual pesticides in the crop. METHODS AND RESULTS: The pesticide granules were treated in soil on two levels, and the plants samples were collected 51 days after seeding. The analytes were extracted and partitioned using the QuEChERS extraction packet (MgSO₄ 4 g, NaCl 1 g). The quantitative methods for metalaxyl-M and dinotefuran were validated in linearity, accuracy, and precision. Risk assessments of the pesticides were performed using Korea national nutrition statistics 2019. CONCLUSION(S): The residual concentrations of metalaxyl-M in crown daisy were 0.09-0.10 mg/kg (for the treatment at 6 kg/10 a) and 0.17-0.19 mg/kg (12 kg/10 a), respectively. The residual concentrations of dinotefuran in the crop were 0.53-0.75 mg/kg (3 kg/10 a) and 1.17-1.26 mg/kg (6 kg/10 a). The amounts of pesticides were less than MRL (Maximum Residue Limits) according to the Korean MFDS (Ministry of Food and Drug Safety). The HI (Hazard Index) of metalaxyl-M and dinotefuran for consumers was 0.0075% and 0.2250%, respectively. For females in the age between 50-64, the major consumer group, the HIs of the pesticides were <3%. Considering the consumption of crown daisy, they are not considered to be of toxicological concern.

• Journal of Environmental Impact Assessment
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• v.31 no.5
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• pp.321-333
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• 2022

In this study, the concentration and distribution characteristics of BTEX (benzene toluene, ethylbenzene, and xylene) emitted from Daesan Petrochemical Industrial Complex were examined to determine their potential hazards to local residents. Residents living nearby the complex areas may be exposed to the chemicals through various media (air, water, and soil), especially by air. This study evaluated human health risks by inhalation using both deterministic and probabilistic risk assessment approaches. As a result of the deterministic risk assessment, the non-cancer risk was much lower than the regulation limit of hazard index (HI 1.0) for all the points. However, in case of cancer risk evaluation, it was found that the risk of excess cancer for benzene at point A located in the industrial complex was 2.28×10^-6, which slightly exceeded the standard regulatory limit of 1.0×10^-6. In addition, the probabilistic risk assessment revealed that the percentile exceeding the standard of 1.0×10^-6was found to be 45.3%. The sensitivity analysis showed that exposure time (ET) had the greatest impact on the results. Based on the risk assessment study, it implied that ethylbenzene, toluene, and xylene had little adverse effects on potential human exposure, but benzene often exceeded the cancer risk standard (1.0×10^-6). Further studies on extensive VOCs monitoring are needed to evaluate the potential risks of industrial complex areas.

• Analytical Science and Technology
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• v.22 no.5
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• pp.386-394
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• 2009

Formaldehyde is used in lether manufacture, a dry plate and an explosive. It is by-product of ozonizing process in filtration plant. The effects of exposure are eye pruritus, tickle, runing nose, blocking nasal passages and headache. It also makes a dried throat and causes inflammation. It is classified as B1 group for inhalation by US. EPA, which can cause cancer in human. For analysis of formaldehyde, formaldehydes-DNPH derivative was extracted with solid cartridge and was analyzed by High Performance Liquid Chromatography/Diode Array Detector (HPLC/DAD). The detection limit was $3{\mu}g/L$ and the recoveries were 72.3~109.1% (RSD 2.9~11.5%). Water samples were collected in four Korean rivers, four times per year seasonally for 10 years from 1998 to 2007. The monitoring results were 48.8% (630/1291), $5.15{\sim}101.9{\mu}g/L$ in purified water. Because of non-carcinogen in drinking water, hazard index is calculated with RfD. Results of excess cnacer risk was below 1 and was considered as safe value.

• Journal of the Korean GEO-environmental Society
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• v.16 no.4
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• pp.5-12
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• 2015

Civil engineers have taken the numerous slope monitoring data for an engineering project subjected to hazard potential of slide. However, the topics on how to deal with and draw out proper information from the data related to the slope behavior have not been widely discussed. Recently, several researchers had installed the real-time monitoring system to cope with slope failure; however they are mainly focused on the hardware system installation. Therefore, this study tries to show how the measured data could be grouped and connected each other. The basic idea of analyzing method studied in this paper came from the clustering, which is the part of data mining analysis. Therefore, at the base of classification of time series data, the authors suggest three mathematical data analyzing methods; Average Index of different displacement ($AD_{i,j}$), Difference of average relative displacement ($\overline{RD}_{i,j}$) and Coordinate system of average and relative displacement ($\overline{RD}$, AD). These analyzing methods are based on the statistical method and failure mechanism of slope. Therefore they showed clustering relationships of the similar parts of the slope which makes the same sliding mechanism.

• Journal of Environmental Health Sciences
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• v.50 no.2
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• pp.146-156
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• 2024

Background: Children who use playground facilities are exposed to potential risks due to the high concentration of heavy metals contained in the finishing materials of facilities in children's playgrounds. Objectives: The purpose of this study was to investigate the concentration of heavy metals in the finishing materials of outdoor children's playgrounds where harmful heavy metals exist in Gwangju and to conduct human risk assessment for children and adults by age to find the risks and limitations. Methods: The bottom and top layers of double-painted paint were peeled off and collected together from the finishing materials of children's play facilities such as slides, swings, and seesaws in 147 children's parks in Gwangju. Heavy metals were analyzed using ICP-OES, etc., and human risk assessment was performed using the concentrations of heavy metals. Results: Based on 1.0E-04, which requires legal regulation, CTE was found to pose a carcinogenic risk for preschool children and no carcinogenic risk for the rest of the age groups. However, RME showed that both men and women of all ages had a carcinogenic risk. For reference, when the carcinogenic risk was based on 1.0E-06, CTE was found to pose a carcinogenic risk from infants to elementary school students, and RME was found to have a carcinogenic risk in all age groups. It was judged that there is a non-carcinogenic risk if the non-carcinogenic risk exceeds 1 based on the hazard index (HI) 1. In CTE, there was no non-carcinogenic risk, and RME for preschooler males (1.49E+00) and females (1.56E+00) were found to have non-carcinogenic risk. Conclusions: This study was meaningful in that it examines the differences in the current management of heavy metals concentration standards and potential carcinogenic and non-carcinogenic risks to the human body and discusses the relationship between heavy metals and human health effects.

• Annals of Occupational and Environmental Medicine
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• v.34
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• pp.15.1-15.9
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• 2022

Background: Most previous longitudinal studies on lifestyle and gastroesophageal reflux disease (GERD) have focused on physical activity rather than sitting time. The main purpose of this study was to investigate the relationship between prolonged sitting time and the development of erosive esophagitis (EE). Methods: A self-report questionnaire was used for measuring sitting time in the Kangbuk Samsung Health Study. Sitting time was categorized into four groups: ≤ 6, 7-8, 9-10, and ≥ 11 hours/day. Esophagogastroduodenoscopy (EGD) was performed by experienced endoscopists who were unawared of the aims of this study. Hazard ratios (HRs) and 95% confidence intervals (CIs) for the development of EE were estimated using Cox proportional hazards analyses with ≤ 6 hours/day sitting time as the reference. Results: There were 6,524 participants included in the study. During a mean follow-up of 3.14 years, 2,048 incident cases developed EE. In age- and sex-adjusted models, the HR in the group sitting ≥ 11 hours per day compared ≤ 6 hours per day was 0.88 (95% CI: 0.76-0.99). After further adjusting for alcohol intake, smoking status, educational level, history of diabetes, and history of dyslipidemia, sitting time was still significantly related to the risk of EE (HR, 0.87; 95% CI: 0.76-0.98). After further adjustment for exercise frequency, this association persisted (HR, 0.86; 95% CI: 0.76-0.98). In subgroup analysis by obesity, the relationship between sitting time and EE was only significant among participants with body mass index < 25 kg/m² (HR, 0.82; 95% CI: 0.71-0.95). Conclusions: Generally, prolonged sitting time is harmful to health, but with regard to EE, it is difficult to conclude that this is the case.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.6
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• pp.1155-1162
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• 2002

Food waste in school foodservices is an important factor in managing expense or evaluating the acceptance of served meals and a serious environmental hazard factor in all countries. In this study, the perception and attitude towards food waste reduction and the recognition of environmental pollution of students from elementary school foodservices in Busan, Korea were investigated. The questionnaire was responded by 519 students (boy: 255, girl: 264) in the third and sixth grades. School lunch programs were proved to contribute to the improvement of students' food intake habits. The perception and attitude towards food waste reduction of the third grade students (3.61/3.73) were significantly higher than those of the sixth grade students (3.46/3.59) (P<0.01). Food waste education made a significant impact on the perception and attitude on food waste (p<0.01). When dislike food was supplied the students having the higher perception and attitude towards food waste reduction ate it more than those having the lower perception and attitude. The major reason for plate waste was shown to be influenced by the taste and amount of foods supplied in school lunch programs. Most of students recognized that food waste pollution (4.22) was one of the severest problems among the environmental pollutions, followed by air (4.13), tap water (4.09) soil (3.78), noise (3.55) pollution. The students separated the garbage in the house (72.6%) better than in school and the outside (55.2%). The perception of food waste was positively correlated with the attitude toward reduction of food waste and the recognition of environmental pollution (p<0.01). The attitude toward reduction of food waste was also positively correlated with meal quantity taken (p<0.01).

• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.4
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• pp.25-34
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• 2010

This study was conducted to develop evaluation indicators to improve athletic performance and operational management of golf courses and the results of the research are as follows. Through theoretical research and a preliminary professional survey, 15 on-going evaluations of golf course composition and operational management and 55 sub-evaluation indices were rejected while 10 on-going evaluations and 52 sub-evaluation indicators were reconfigured as final for environmental-friendliness, level of member services, level of human service of game personnel, difficulties of course, management level of the course, fairness of operational management, accessibility and location characteristic, traditions and ambiance of the golf club, quality of course, and course layout. When analyzing the important decision factors in golf course user preference evaluation indicators, the following contributed in the order of higher to lower contributions: the management level of the course, excellence of the course, level of human services for personnel, course layout and environmental-friendliness. When identifying the path coefficient of golf course evaluation indicators, the curvature of a hole and the length of the course had a causal effect on the 'course layout' section. Tournament facilities and various shot values had a causal relationship with 'excellence of the course', in the order of higher to lower, and convenience of waiting and fair allocation of reservations for 'fairness of operational management'. The history of the golf course and its environmental characteristics, history and culture of the region have relatively higher causal effects on 'traditions of the golf club' and geographical conditions on 'accessibility and location characteristics', pesticide and fertilizer usage and water pollution on 'environmental-friendliness', and member benefit and kindness of employees on 'level of member services'. The kindness and expertise of the game personnel had a relatively higher causal effect on the 'level of human services of game personnel', the location of tenning area, and location of OB and hazards on 'difficulties of course', and rough conditions and obstacles management on 'management level of the course'. There is a need to complete a systematic evaluation index system for golf course user preferences through future studies for a more detailed assessment, as well as a process to verify these evaluation indicators by application to domestic and international golf courses.

• Economic and Environmental Geology
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• v.40 no.5
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• pp.651-660
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• 2007

Acid drainage has been recognized as an environmental concern in abandoned mine sites for long time. Recently, the environmental and structural damage by acid drainage is a current issue in construction sites in Korea. Here, the author introduces the type of damages by acid drainage in construction sites and emphasizes the importance of geoscience discipline in solving the problem. Metasedimentary rock of Okcheon group, coal bed of Pyeongan group, Mesozoic volcanic rock. and Tertiary sedimentary and volcanic rocks are the major rock types with a high potential for acid drainage upon excavation in Korea. The acid drainage causes the acidification and heavy metal contamination of soil, surface water and groundwater, the reduction of slope stability, the corrosion of slope structure, the damage on plant growth, the damage on landscape and the deterioration of concrete and asphalt pavement. The countermeasure for acid drainage is the treatment of acid drainage and the prevention of acid drainage. The treatment of acid drainage can be classified into active and passive treatments depending on the degree of natural process in the treatment. Removal of oxidants, reduction of oxidant generation and encapsulation of sulfide are employed for the prevention of acid drainage generation.