• Journal of Environmental Health Sciences
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• v.42 no.1
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• pp.1-9
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• 2016

Objectives: Personal exposure to air pollution is affected by contact over time and by location. The purpose of this study was to determine the relationship between personal exposure to $PM_{2.5}$ and the time-activity patterns of the elderly in urban and rural areas. Methods: A total of 44 elderly participants were recruited for a 24-hour $PM_{2.5}$ personal exposure measurement. Twenty-four were from Seoul (urban area) and 20 were from Asan (rural area). Energy expenditure and spatiotemporal positioning were monitored through $PM_{2.5}$ measurement. Spearman correlation analysis was conducted to determine the relationship between $PM_{2.5}$ and time-activity pattern. Results: Daily average $PM_{2.5}$ personal exposures were $19.1{\pm}9.7{\mu}g/m^3$ in Seoul and $29.1{\pm}16.9{\mu}g/m^3$ in Asan. Although outdoor exposure was higher in Seoul than in Asan, residential indoor exposure was higher in Asan than in Seoul. Higher $PM_{2.5}$ personal exposure in Asan could be explained by longer time in residential indoor environments and higher indoor $PM_{2.5}$ concentrations. Seoul elderly had higher energy expenditure, which may be due to the use of mass transportation. Conclusion: Personal exposure to $PM_{2.5}$ was higher among Asan elderly than Seoul elderly because of high residential indoor concentrations and longer residential time. Lack of energy spent and higher personal exposure to $PM_{2.5}$ might have led to higher risk among the Asan elderly.

• Journal of Korean Society on Water Environment
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• v.20 no.2
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• pp.120-125
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• 2004

Exposure to volatile disinfection by-products (DBPs) such as chloroform included in chlorinated tap water can occur during household activities via inhalation as well as ingestion and dermal absorption. This study was conducted to examine the significance of inhalation route of exposure since humans are unintentionally exposed to volatile DBPs while staying home. Two sets of experiments were carried out in an apartment to measure: 1) the variation of chloroform concentrations in the living room air following kitchen activities (cooking and dish-washing); and 2) the variation of chloroform concentrations in the bathroom and living room following showering. Cooking, dish-washing, and showering all contributed to the elevation of household chloroform levels. Even a few minutes of natural ventilation resulted in the reduction of the chloroform levels to the background. Estimates of daily chloroform doses and lifetime cancer risks suggested that inhalation of household air during staying home be a major route of exposure to chloroform and that ingestion be a minor one in Korean people. It is also suggested that ventilation be a simple and important measure of mitigating human exposure to volatile DBPs indoors.

• Journal of Korean Society for Atmospheric Environment
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• v.25 no.4
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• pp.339-346
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• 2009

The objectives of this study were to introduce spatial interpolation methods which have been applied in recent papers, to apply three methods (nearest monitor, inverse distance weighting, kriging) to domestic data (Ulsan cohort) as an example of estimating the personal exposure levels. We predicted the personal exposure estimates of 2,102 participants in Ulsan cohort using spatial interpolation methods based on information of their residential address. We found that there was a similar tendency among the estimates of each method. The correlation coefficients between predictions from pairs of interpolation methods (except for the correlation coefficient between nearest montitor and kriging of CO and $SO_2$) were generally high (r=0.84 to 0.96). Even if there are some limitations such as location and density of monitoring station, spatial interpolation methods can reflect spatial aspects of air pollutant and spatial heterogeneity in individual level so that they provide more accurate estimates than monitor data alone. But they may still result in misclassification of exposure. To minimize misclassification for better estimates, we need to consider individual characteristics such as daily activity pattern.

• Development and Reproduction
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• v.25 no.4
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• pp.293-298
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• 2021

Di(2-ethylhexyl)phthalate (DEHP) could induce metabolic disorders through interfering with thyroid homeostasis. Therefore, we evaluated the effects of short term to environmental relevant doses of DEHP on thyroid hormones. Four week old Sprague-Dawley (SD) rats were treated with vehicle (corn oil), and DEHP 0.75, 7.5, and 150 mg/kg/day. The rats were treated with once daily by oral gavage and were sacrificed with after 1 week. They were measured body weight and relative thyroid weight, serum thyroid hormones and histological changes of thyroid. There was no difference in body weight between the control and DEHP exposed rats. Relative thyroid weight in DEHP 150 mg/kg/day treated group was significantly lower than control. Serum thyroxine levels was decreased in rats exposed to 0.75 and 150 mg/kg/day DEHP. No histological changes were observed in the thyroid of rats administered DEHP compared to control. Exposure to DEHP at environmental relevant levels, even short-term exposure, can cause hypothyroidism in adolescent rats even the exposure period is relative short.

• Journal of the East Asian Society of Dietary Life
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• v.7 no.1
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• pp.41-46
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• 1997

Diet is generally accepted as one of the important factors in human cancer development. Ethyl carbamate has been associated with cancer for several decades and mainly found in the fermented beverages and foodstuff. The relationship between ethyl carbamate and the human health cannot be ignored especially in the areas where fermented foods consists of regular food consumption. To investigate the ethyl carbamate exposure level in Korean population, commercial fermented food samples were collected form local markets I Seoul area and home-made varieties were collected throughout the country. Following partial purification the concentration of ethyl carbamete was determined by GC/ MS. The concentration of ethyl carbamate ranged to 70 ppb in soysauce, to 10 ppb in soybean paste, and to 5 ppb in vinegars. Korean traditional alcoholic beverages showed small amount of ethyl carbamate. The estimated daily exposure of Korean population was 0~1900ng/day. It would be prudent to put efforts to minimize the formation of ethyl carbamate since the risk from the higher range exposure cannot be ignored.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11a
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• pp.131-134
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• 2005

This study examine the annoyance of transportation noise exposure and found the survey method about which noise induces more disturbance or annoyance when more than two kinds of noise exist. This study describes the noise annoyance survey performed in the vicinity of Sin-wol interchange. This residential area was exposed to aircraft noise and traffic noise simultaneously and aircraft noise exposure of this area is about 81 WECPNL, traffic noise exposure is about 81.2 dB(A) nearby road. Noise sources are grouped into three part, traffic noise, aircraft noise and community noise. The questionnaire includes how often, how loud each noise is heard. Also this deals with comparative annoyance reaction from specific noise sources such as aircraft or traffic and its disturbance of daily activities. Facade noise mapping are executed by using a commercial noise mapping software.

• Korean Journal of Occupational Health Nursing
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• v.31 no.2
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• pp.95-103
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• 2022

Purpose: This study aims to identify general, workplace, and health-related characteristics of outdoor workers exposed to high temperatures, and to compare the risk of disease according to outdoor high temperature exposure. Methods: This secondary analysis study used the 5th Korean Working Conditions Survey (2017) to identify 4,915 outdoor workers exposed to high temperatures. Results: Outdoor workers exposed to high temperatures were mostly male, elderly, less educated, and daily contract workers. Most of them were engaged in agriculture, forestry and fishing, and construction industries. About 40~50% of them complained of musculoskeletal pain and overall fatigue. The results showed that high temperature exposure increased the risk of illness (hearing problem, skin problem, backache, muscular pains in upper and lower limbs, headache/eyestrain, injuries, depression, and overall fatigue) among workers. Conclusion: High temperature exposure might increase the risk of illness among workers. The results of this study demonstrated that the outdoor workers should be protected from high temperatures.

• Asian-Australasian Journal of Animal Sciences
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• v.2 no.3
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• pp.206-207
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• 1989

• Proceedings of the Korean Environmental Health Society Conference
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• 2005.12a
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• pp.23-34
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• 2005

• 대한예방의학회:학술대회논문집
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• 1999.10a
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• pp.306-307
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• 1999