• Journal of Environmental Health Sciences
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• v.42 no.3
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• pp.205-212
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• 2016

Objectives: The objective of this study was to evaluate the distribution of blood lead concentrations of residents in the areas surrounding an industrial complex. Methods: During the three-month period from August to October 2012, informed consent was obtained from a total of 417 residents in Gwangyang and Yeosu. We collected blood samples from all subjects, and their demographic characteristics were acquired using a questionnaire. The blood samples were analyzed using an atomic absorption spectrometer and data analysis was conducted using IBM SPSS version 21.0. Results: The geometric mean concentration of blood lead in all subjects was $1.85{\mu}g/dL$. The highest (p<0.01) blood lead concentrations were in the current drinking group ($2.24{\mu}g/dL$). Blood lead concentrations in the smoking group ($0.59{\mu}g/dL$) were significantly (p<0.05) higher than those in the non-smoking group ($0.24{\mu}g/dL$). Risk assessment was performe using the Korean National Environmental Health Survey (KNEHS) as a reference. The hazard indices of blood lead in males and females were 0.65 and 0.52, respectively Conclusion: We provided baseline data for reference values of toxicity and heavy lead concentrations. Our results might be useful for further evaluation of risks due to exposure to heavy metals via oral, air, and percutaneous routes.

• Toxicological Research
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• v.17
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• pp.323-327
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• 2001

March 19, 1999, the renovation qf the runway of the Bo-Fai ai1field in Hua Hin, Prachubk-erikhan, Thailand, unearthed chemicals which were left over from the project "anch Hand Operation" held during the Vietnam war era. The chemical mixtures were analyzed by the US EPA, the Department oj Medical Sciences (DMSc), Ministry oj Public Health (MoPH) and the Pollution Control Department (PCD), the Ministry oj Science Technology and Environment (MOSTE) of Thailand, The samples were found to contain several defoliants used in the operation. They were 2,4-D, 2,4,5-T, Dicamba, Cocydelic acid, and Dioxins. Due to the complexity of the issue, the multiplicity of possible health effects, and the socio-economic implications for imports and exports, the Thai Society of Toxicology submitted a proposal to request World Health Organization (WHO), Geneva. The assistance is for the area of chemical safety and called for immediate action to explore the magnitude qf risk involved with Dioxins. In this paper we present our approach to health risk assessment which takes into an account the epidemiological studies of high-risk group exposed to the Ranch Hand operation. Dioxins are endocrine disruption chemicals which public concerns are developed due to presumption that a hazard exists (www.eva.gov/dioxins/html) for which current methodologies are deemed insufficient. The recent concepts of how oxidative stress toxicants may affect health end points and biomarkers of exposure of exposed individuals are discussed. While research activities are undergoing, The Thai Society of Toxicology do not anticipate significant risk to local residents and the environment due to our concurrence with opinion from the international experts invited by the World Health Organization proposed to the local experts at a workshop in Bangkok.n Bangkok.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2003.05a
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• pp.194-194
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• 2003

The International Agency for Research on Cancer (IARC, 1989) has classified whole diesel exhaust as probably carcinogenic to humans. Diesel exhaust particulate matter (DPM) adsorbs different chemical substances including PAHs and nitroarenes. DPM is emphasized because it is a major component of diesel exhaust, it is suspected of contributing to a health hazard. Diesel exhaust is a complex mixture of carbon particles and associated organics and inorganics, and it is not known what fraction or combination of fractions cause the health effects [cancer effects, noncancer effects (respiratory tract irritation/inflammation and changes in lung function)] that have been observed with exposure to diesel exhaust. In order to identify which chemical classes are responsible for the majority of the observed biological activities, we performed a particular biological/chemical analysis. Respirable particulate matter (PM2.5: <2.5mm) was collected from diesel engine exhaust using a high-volume sampler equipped with a cascade impactor. Particulate oganic matter was extracted by the dichloromethane/sonication method and the crude extract was fractionated according to EPA recommended procedure into seven fractions by acid-base partitioning and silica gel column chromatography. We examined genotoxic potentials of diesel exhaust particulate matter using novel genotoxicity tests, which are rapid, simple and sensitive methods for assessing DNA-damage at the DNA and chromosomal level (comet assay, in vitro MN test and Ames test). Higher genotoxic potency was observed in non polar fractions and several PAHs were detected by GC-MS, such as 1,2,5,6 dibenzanthracene, chrysene, 1,2-benzanthracene, phenanthrene and fluoranthene.

• Journal of Applied Biological Chemistry
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• v.56 no.4
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• pp.191-197
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• 2013

To classify the chemical hazard according to globally harmonized system of classification and labeling of chemicals (GHS), we investigated the genotoxicity of three chemicals, methyl myristate, 2-ethylhexanoic acid zinc salt, N,N,N',N'-tetrakis(2-hydroxyethyl) ethylenediamine, using male ICR mice bone marrow cells for the screening of micronucleus induction. Although these three chemicals have already been tested numerous times, a micronucleus test has not been conducted. The seven week-old male ICR mice were tested at three dosages for the three chemicals, respectively. After 24 h of oral administration with the three chemicals, the mice were sacrificed and their bone marrow cells were prepared for smearing slides. As a result of counting the micronucleated polychromatic erythrocyte (MNPCE) of 2,000 polychromatic erythrocytes, all treated groups expressed no statistically significant increase of MNPCE compared to the negative control group. There were no clinical signs related with the oral exposure of these three chemicals. It was concluded that these three chemicals did not induce micronucleus in the bone marrow cells of ICR mice, and there was no direct proportion with dosage. These results indicate that the three chemicals have no mutagenic potential under each test condition, and it is not classified these chemicals as mutagens by GHS.

• Environmental Analysis Health and Toxicology
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• v.25 no.1
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• pp.41-55
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• 2010

The aims of this study were to develop the suitable "system software" in chemical ranking and scoring (CRS) for the food hazardous chemicals associated with environmental emission and to suggest the priority lists of food contamination by environmental-origined pollutants. Study materials were selected with reference to the priority pollutants list for environment and food management from domestic and foreign research and the number of study materials is 103 pollutants (18 heavy metals, 10 PBTs, 10 EDs, and 65 organic compounds). The Food-CRS-Korea system consisted of the environmental fate model via multimedia, transfer environment to food model, and health risk assessment by contaminated food intake. We have established that health risks of excess cancer risks, hazard quotients (HQs) by chronic toxicity and HQs by reproductive toxicity convert to score, respectively. The creditable scoring system was designed to consider uncertainty of quantitative risk assessment based on VOI (Value-Of-Information). The predictability of the Food-CRS-Korea model was evaluated by comparing the presumable values and the measured ones of the environmental media and foodstuffs. The priority lists based on emissions with background-level-correction are 15 pollutants such as arsenic, cadmium, and etc. The priority lists based on environmental monitoring date are 17 pollutants including DEHP, TCDD, and so on. Consequently, we suggested the priority lists of 13 pollutants by considering the several emission and exposure scenarios. According to the Food-CRS-Korea system, arsenics, cadmium, chromes, DEHP, leads, and nickels have high health risk rates and reliable grades.

• Environmental Analysis Health and Toxicology
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• v.25 no.1
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• pp.57-68
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• 2010

This study assessed the lifetime cancer and non-cancer risk of aldehydes and volatile organic compounds exposure of young children at child-care facilities and indoor playgrounds in Korea. The samples were collected at various children's facilities (40 day-care houses, 42 child-care centers, 44 kindergartens, and 42 indoor playgrounds) in summer (Jul~Sep, 2007), winter (Jan~Feb, 2008) and Spring (Mar~Apr, 2008) periods, and analyzed by GC-MS. We estimated the lifetime excess cancer risks (ECRs) of formaldehyde, acetaldehyde, benzene, chloroform, CCI4 and tetrachloroethylene, and the hazard quotients (HQs) of Non-carcinogens (toluene, xylene, benzaldehyde and formaldehyde). Formaldehyde evaluated both cancer and non-cancer risk. The average ECRs of formaldehyde for young children were $1\times10^{-4}{\sim}1\times10^{-5}$ level in all facilities. HQs of four non-carcinogens did not exceed 1.0 for all subjects in all facilities.

• KCID journal
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• v.18 no.2
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• pp.33-42
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• 2011

Climate change has impacts on not only the average temperature rise but also the intensity and frequency of extreme events such as flood and drought. It is also expected that the damages on agricultural infrastructure will be increased resulting from increased rainfall intensity and frequency caused by climate change. To strengthen the climate change adaptation capacity, it is necessary to identify the vulnerability of a given society's physical infrastructures and to develop appropriate adaptation strategies with infrastructure management because generally facilities related to human settlements are vulnerable to climate changes and establishing an adaptive public infrastructure would reduce the damages and the repair cost. Therefore, development of mitigation strategies for agricultural infrastructure against climatic hazard is very important, but there are few studies on agricultural infrastructure vulnerability assessment and adaptation strategies. The concept of vulnerability, however, is difficult to functionally define due to the fact that vulnerability itself includes many aspects (biological, socioeconomic, etc.) in various sectors. As such, much research on vulnerability has used indicators which are useful for standardization and aggregation. In this study, for the vulnerability assessment for agricultural infrastructure, 3 categories of climate exposure, sensitivity, and adaptation capacity were defined which are composed of 16 sub-categories and 49 proxy variables. Database for each proxy variables was established based on local administrative province. Future studies are required to define the weighting factor and standardization method to calculate the vulnerability indicator for agricultural infrastructure against climate change.

• Journal of Gastric Cancer
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• v.14 no.4
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• pp.252-258
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• 2014

Purpose: The macroscopic diagnosis of tumor invasion through the serosa during surgery is not always distinct in patients with gastric cancer. The prognostic impact of the difference between macroscopic findings and pathological diagnosis of serosal invasion is not fully elucidated and needs to be re-evaluated. Materials and Methods: A total of 370 patients with locally advanced pT2 to pT4a gastric cancer who underwent curative surgery were enrolled in this study. Among them, 155 patients with pT3 were divided into three groups according to the intraoperative macroscopic diagnosis of serosal invasion, as follows: serosa exposure (SE)(-) (no invasion, 72 patients), SE(${\pm}$) (ambiguous, 47 patients), and SE(+) (definite invasion, 36 patients), and the clinicopathological features, surgical outcomes, and disease-free survival (DFS) were analyzed. Results: A comparison of the 5-year DFS between pT3_SE(-) and pT2 groups and between pT3_SE(+) and pT4a groups revealed that the differences were not statistically significant. In addition, in a subgroup analysis of pT3 patients, the 5-year DFS was 75.1% in SE(-), 68.5% in SE(${\pm}$), and 39.4% in SE(+) patients (P<0.05). In a multivariate analysis to evaluate risk factors for tumor recurrence, macroscopic diagnosis (hazard ratio [HR], SE(-) : SE(${\pm}$) : SE(+)=1 : 1.01 : 2.45, P=0.019) and lymph node metastasis (HR, N0 : N1 : N2 : N3=1 : 1.45 : 2.20 : 9.82, P<0.001) were independent risk factors for recurrence. Conclusions: Gross inspection of serosal invasion by the surgeon had a strong impact on tumor recurrence in gastric cancer patients. Consequently, the gross appearance of serosal invasion should be considered as a factor for predicting patients' prognosis.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.10 no.2
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• pp.150-164
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• 2000

This study was conducted at occupational health laboratories in Seoul and Gyunggi district area from December, 1999 to January, 2000. The main purpose of this study was to survey the actual condition of safety and health by questionnaire and checklist and to assess the performance of fume hoods and the airborne exposures to chemicals in the laboratories. The chemicals in the cabinet were not classified by hazardous properties and the compressed gases were not stored safely. The prevalences of laboratories having first aid kits, fire extinguishers, and safety showers were found to be 18%, 55%, and 9%, respectively. Most laboratory workers were not educated for safety and health. Also, there was no performance evaluation for hazards and risks. The fume hoods in laboratories had not been annually inspected by checklist and the face velocity had been checked more than one time in the previous year for only 18% of them. Five percent of fume hoods had the face velocity more than 4.0 m/sec and 17% had no capture performance. Detected organic solvents were methylenechloride, acetone, ethylbenzene, isopropanol, xylene, methylisobutylketone, trichloroethylene, and toluene. The concentrations of organic solvents were much less than the occupational exposure limits proposed by the Ministry of Labor in Korea. This study showed that the actual condition of safety and health was not appropriate for laboratory workers. It is recommended that laboratory workers should be educated for the treatment and storage of hazardous chemicals and compressed gases to improve the working environment of the occupational safety and health laboratories.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.16 no.1
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• pp.166-175
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• 2017

Hazardous volcanic activity will continue to occur in the ring of fire, a major area in the basin of the Pacific Ocean where a large number of earthquakes and volcanic eruptions occur. and, because of rising populations, development pressures, and expanding national and international air traffic over volcanic regions, risks to life and property through exposure to volcano hazards continue to increase. During an eruption, volcanic contamination can reach and exceed the cruising altitudes of turbine-powered aircraft, among others, within minutes and spread over vast geographical areas within a few days. Volcanic ash can affect the operation of aircraft at aerodromes. Volcanic ash deposition at an aerodrome, even in very small amounts, can result in the closure of the aerodrome until all the deposited ash has been removed. In this study, air traffic information framework is presented along with algorithms to define affected routes, waypoints and airports using GIS geometry analysis.