• 약학회지
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• 제41권6호
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• pp.789-796
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• 1997

The purpose of this study was to determine the effect of sulfinpyrazone on fumonisin $B_1$-induced elevation of free sphingoid bases in LLC-$PK_1$ cells. Fumonis ins are a family of mycotoxins produced by the fungi Fusarium moniliforme which is common contaminant in corn. Fumonisins are also potent inhibiors of sphingosine and sphinganine N-acyltransferases (ceramide synthases), key enzymes in sphingolipid metabolism resulting in the elevation of free sphinganine. The cytosolic concentration of fumonisin B1 was known to be closely proportional to the elevation of free sphinganine in LLC-PK1 cells [Yoo, H.-S., Norred, W.P., Wang, E., Merrill, A.H., Jr., and Riley, R.T. (1992) Toxicol. Appl.Pharmacol. 114. 9-15]. Sulfinpyrazone, an anion transport inhibitor, reduced the elevated level of free sphinganine resulting from fumonisin B1 inhibition of de novo sphingolipid biosynthesis. Fumonisin B1 at a concentration of 20${\mu}$M showed approximately 120pmol/$10^6$ cells relative to 3-10pmol/$10^6$ cells in control cultures, and sulfinpyrazone at a concentration of 200${\mu}$M partially reversed the increased level of free sphinganine induced by fumonisin $B_1$ down to normal level after exposure to fumonisin $B_1$ for 8 to 24hr. However, the reduced effect of sulfinpyrazone on the fumonisin $B_1$-induced elevation of intracellular sphinganine was not shown after 24hr. Fumonisin $B_1$ exposure to LLC-PK1 cells for 36 and 48hr showed approximately 74 and 80pmol per $10^6$ cells relative to 82 and 76pmol,respectively, in fumonisin $B_1$ plus sulfinpyrazone-treated cultures. Sulfinpyrazone-induced less elevation of free sphinganine in confluent cells after exposure to fumonisin $B_1$ suggested that either sulfinpyrazone may block the availability of fumonisin $B_1$ to cells or act on the fumonisin $B_1$ interaction with ceramide synthase.

• 한국환경보건학회지
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• 제48권1호
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• pp.44-51
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• 2022

Background: Air pollution is increasing together with industrialization and urbanization. In order to reduce air pollution, public transportation is recommended rather than private cars, and the number of passengers using public transportation is increasing accordingly. This study observes the concentration of indoor pollutants in city buses over time. Through this means, we intend to suggest a plan to manage the indoor air quality in city buses. Objectives: The concentration of indoor pollution in public transportation was investigated from April 2021 to January 2022. Based on this, we evaluated the exposure to indoor pollutants. Methods: Six city bus lines in an industrial city were selected for the research, and indoor pollution was measured through IoT (Internet of Things)-based sensor-type measuring devices. The concentration of pollutants was measured every minute, and statistical data were constructed based on the measurement results. Results: In all the city buses studied, the average concentration of pollutants were below the guidelines. However, some measurement results showed cases of exceeding the guidelines. As a result of the analysis by time zone, there were more cases in which pollutants exceeded the standard value during rush hour compared to at other times. A risk assessment for PM₁₀ was performed by evaluating the excess mortality risk from exposure and the risk from inhalation exposure. Conclusions: All measured indoor pollutants in the city buses did not exceed the guidelines. Also, the risk assessment results were found to be within the level of safety. However, if a city bus is used for a long time, there is a possibility that there may be an impact on the human body due to inhalation exposure, so additional management is required.

• Journal of Preventive Medicine and Public Health
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• 제34권1호
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• pp.80-88
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• 2001

Objectives : In an epidemiologic study on the health impact of Agent Orange exposure, the valid estimation of exposure level is the most important step. Based on recent studies, we examined the correlation between exposure levels categorized by personal exposure estimates and serum 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD, Dioxin), exploring the possibility of utilizing the exposure level as a surrogate for the estimate of exposure to agent orange. Methods : During the study period (Jan 1996-Feb 1996), blood specimens of 745 subjects taken randomly among 1,329 persons and kept frozen, were analyzed for 2,3,7,8-TCDO and six other dioxin congeners. The serum dioxin and congeners were measured in 1998 by CDC, adjusted for serum lipids. We categorized the total exposure scores into five groups based on Agent Orange exposure data collected by interview and military records. Pearson and Spearman's correlation coefficients & multiple regression analysis were used to identify the relationship of the exposure level categorized with serum concentration of 2,3,7,8-TCDD, and six other dioxin congeners. Results : Dioxin and the other congeners, except 1,2,4,6,7,8-HpCDD, showed significant correlations to exposure categories (p<0.005): 2,3,7,8-TCDD and OCDD showed positive correlations, whereas the other congeners did negative. The values of 2,3,7,8-TCDD differed according to exposure category and proportionally increased from the low exposure group to the high, a dose-response relationship, even after other possible confounding variables were adjusted for. In multiple regression analysis, age$(\beta=0.033)$, dioxin$(\beta=0.433)$, 1,2,3,7,8-PeCDD$(\beta=-0.998)$, 1,2,3,4,7,8-HxCDD$(\beta=-0.773)$, 1,2,3,6,7,8-HxCDD$(\beta=0.255)$, 1,2,3,7,8,9-HxCDD$(\beta=-3.468)$, 1,2,3,4,6,7,8-HpCDD$(\beta=0.109)$ we re found to be significantly related to the total exposure score(p<0.005). Conclusion : This study demonstrated that the use of such categorizations as a surrogate measure of agent orange exposure in identifying exposure degrees in a health impact study is valid.

• 한국산업보건학회지
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• 제7권2호
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• pp.161-170
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• 1997

본 연구는 사업장 근로자의 스타이렌 폭로수준과 이에 따른 biological monitoring 농도의 변화를 알기 위하여 시도되었다. 조사대상자는 FRP공장, 함침작업공장, 피막도포작업공장에 종사하는 남자근로자 64명과 여자근로자 44명이며 포집 및 분석기간은 1995년 6월 15일부터 9월 30일까지 였다. 일반적 특성중 연령, 성별, 근무경력, 음주량, 흡연량은 설문지를 이용하였고 신장과 체중은 개인건강기록표를, 스타이렌 환경폭로농도를 알기 위하여는 확산형 포집기를 사용하였으며, 생물학적 감시물질의 폭로수준을 알기 위하여 혈액과 소변을 채취하여 혈중 스타이렌, 요중 mandelic acid(MA)와 phenylglyoxylic acid(PGA)을 분석하였다. 평균폭로농도는 21.0ppm으로 저농도였으며 사업장별로는 선박관련업체가, 작업방법으로는 적층작업이, 작업형태는 주작업에서 가장 높은 폭로를 보였으며 대상자 중 11%가 허용기준 이상으로 폭로되었다. 환경폭로수준과 혈중 스타이렌의 상관성은 0.620이었고 creatinine으로 보정한 phenylglyoxylic acid와는 0.702로 가장 높은 상관성을 보였다. 혈중 스타이렌과 요중 대사산물의 상관관계는 MA+PGA에서 가장 높은 상관성을 보였다. 생물학적 대사산물의 변화를 설명하는 독립변수들 중 환경폭로농도가 가장 중요하였으며 특히 MA와 MA+PGA에서는 성별 역시 중요한 변수였다. 생물학적 대사산물에 대한 독립변수의 설명력은 모두 31% 이상이었으며 그중 혈중 스타이렌은 49.1%로 가장 높았다. 요중 대사산물을 보정여부에 따른 상관성을 본 결과 모두 0.95이상을 보였다. 이상을 종합한 바 스타이렌 취급작업장의 공기중 농도를 측정할 때 확산포집기로도 사용할 수 있으며, 요의 생물학적 지표에서는 비중으로 보정한 경우가 creatinine으로 보정한 것의 대안으로 사용할 수 있고 또한 요중 MA 및 PGA를 이용하여 폭로 근로자의 폭로농도를 예측할 수 있으므로 이를 스타이렌 취급근로자에 적극적인 활용이 필요한 것으로 제시할 수 있다.

• 대한환경공학회지
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• 제27권10호
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• pp.1090-1098
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• 2005

벤조일 퍼록사이드는 수서생물에 대해 매우 높은 독성을 나타냄에도 불구하고 환경 중 잔류 농도 및 노출영향에 대해 연구가 이루어지지 않아 OECD에서 추천하고 있는 대표적인 다매체 환경거동 모델인 EQC 모델을 이용하여 본 물질에 대한 환경중의 농도를 예측하고 위해성평가 및 화학물질의 관리를 수행하기 위한 기초자료로 활용코자 하였다. 평형, 정상상태에서 100,000 kg의 벤조일 퍼록사이드가 환경내로 유입된 상태를 나타내는 Level I과 평형, 정상상태 이류와 분해현상이 있고 일정한 속도 1,000 kg/h로 유입되었을 경우를 나타내는 Level II에서 벤조일 퍼록사이드는 주로 토양(68.3%)과 물(28.7%)로 배출되는 것으로 예측되었다. 비평형, 정상상태, 이류와 분해현상이 있고 다매체 이동을 하는 시스템에서 벤조일 퍼록사이드가 대기, 물, 토양, 침전물의 각각의 4개 매체에 연속적으로 1,000 kg/h로 유입될 경우인 Level III에서는 주로 토양(99.9%)으로 배출되었고 전체 잔류시간은 3.4년으로 예측되어 벤조일 퍼록사이드가 환경 중에 잔류성이 있는 물질로 평가되었다.

• Asian Pacific Journal of Cancer Prevention
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• 제16권8호
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• pp.3183-3188
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• 2015

Objective: This study aimed to evaluate the prevalence of skin lesions, which is a health effect of chronic arsenic (As) exposure, and determine the hair/blood arsenic concentrations of people living in Kutahya villages who are using and drinking tap water with a high concentration of arsenic. Materials and Methods: A total of 303 people were included in the present cross-sectional study. A prepared questionnaire form was used to collect the participants' information and environmental history. Skin examination was performed on all participants. Hair, blood and water samples were analyzed using atomic absorption spectroscopy. The cumulative arsenic index (CAI) was calculated for all participants. Results: Villages were divided into two groups according to the arsenic level (<$20{\mu}g/L$, Group I; >$20{\mu}g/L$, Group II) in their water. The prevalence of skin lesions, hair and blood arsenic level, and CAI were found to be higher in the Group II participants. There was a positive association between body arsenic levels and CAI in the participants of each group. Conclusions: The number of skin lesions and arsenic concentrations in body samples were found to increase with the water arsenic level and exposure time. We hope that sharing this study's results with local administrators will help accelerate the rehabilitation of water sources in Kutahya.

• Safety and Health at Work
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• 제10권1호
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• pp.109-113
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• 2019

Background: In both developed and developing countries, noise is regarded as the most common occupational hazard in various industries. The present study aimed to examine the effect of sound pressure level (SPL) on serum cortisol concentration in three different times during the night shift. Methods: This case-control study was conducted among 75 workers of an industrial and mining firm in 2017. The participants were assigned to one of the three groups (one control and two case groups), with an equal number of workers (25 participants) in each group. Following the ISO 9612 standard, dosimetry was adopted to evaluate equivalent SPL using a TES-1345 dosimeter. The influence of SPL on serum cortisol concentration was measured during the night shift. The serum cortisol concentration was measured using a radioimmunoassay (RIA) test in the laboratory. Repeated measure analysis of variance and linear mixed models were used with ${\alpha}=0.05$. Results: The results indicated a downward trend in the serum cortisol concentration of the three groups during the night shift. Both SPL and exposure time significantly affected cortisol concentration (p < 0.0001, p < 0.0001). Conversely, age and body mass index had no significant influence on cortisol concentration (p = 0.360, p = 0.62). Conclusion: Based on the obtained results, increasing SPL will lead to enhancement of serum cortisol concentration. Given that cortisol concentration varies while workers are exposed to different SPLs, this hormone can be used as a biomarker to study the effect of noise-induced stress.

• 한국환경과학회지
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• 제17권9호
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• pp.1005-1013
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• 2008

In this study, in order to analyze the air quality of the indoor environments of schools, we measured the indoor, outdoor and personal exposure concentration level of $PM_{10}$ for 40 classrooms(20 old, 20 new) in chungnam area from June 22 to July 19 and from November 21 to December 30, 2003. 1. Old classrooms contained more dust than new classrooms; the average of respirable dust is $43.27\;{\mu}g/m^3$ for new classrooms while $53.38\;{\mu}g/m^3$ for old one. The exposure concentration level of respirable dust in new classrooms were in summer higher outdoors than indoors. The values were indoors $46.71\;{\mu}g/m^3$, outdoors $50.46\;{\mu}g/m^3$, and personal $41.62\;{\mu}g/m^3$. Meanwhile in winter indoors had a higher concentration level than outdoors, the values being indoors $39.11\;{\mu}g/m^3$, outdoors $34.86\;{\mu}g/m^3$, and personal $49.01\;{\mu}g/m^3$. 2. Cr concentration level within dust was slightly higher in summer indoors ($101.50{\pm}32.10\;ng/m^3$) and outdoors ($100.89{\pm}35.18\;ng/m^3$) than winter indoors ($85.80{\pm}48.95\;ng/m^3$) and outdoors ($74.43{\pm}38.93\;ng/m^3$), but in personal concentration level, winter was higher. The results of this research show insufficient understanding of health risks from indoor air pollution, and shows possible health problems to students from school indoor air pollution. As such, a logical and systematic education program for students about the importance of indoor air quality should be carried out. Also the results of $PM_{10}$ concentration level measurements emphasize the need for regular measurements of indoor / outdoor and personal concentration level. New classrooms in particular needs to be used after measuring pollutants and safety, and requires installation of a ventilation device in all classrooms to improve air quality.

• 한국산업보건학회지
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• 제34권3호
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• pp.262-278
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• 2024

Objectives: To investigate the work environment measurement (WEM) status and concentration levels of substances with short-term exposure limits (STEL) among special management substances. Methods: Data from the past 5 years of WEM for 6 substances (1,2-dichloropropane (1,2-DCP), 1,3-butadiene, benzene, trichloroethylene (TCE), perchloroethylene (PCE) and sulfuric acid) were analyzed. The number of samples and concentration level of STEL and 8-hour TWA (time weighted average) were compared. Results: The number of STEL measurement for 1,3-butadiene, benzene, and sulfuric acid was less than 1% of the number of TWA measurement samples, while TCE, 1,2-DCP, and PCE, which are mainly used for cleaning metals, were relatively high, at 16.1%, 5.6%, and 2.2%, respectively. When comparing the concentrations of STEL with TWA on the same STEL measured workers (STEL-matched TWA), STEL concentrations were 2.8, 3.1, 2.6, 2.6 and 40.5 times higher than TWA as 1,2-DCP, benzene, TCE, PCE, and sulfuric acid. When comparing the concentration of STEL-matched TWA with the total TWA, STEL-matched TWA was 3.4, 8, 1.4, 2.0, 8.6 and 0.7 times higher for 1,2-DCP, benzene, 1,3-butadiene, TCE, PCE, and sulfuric acid, respectively. Conclusions: This study found that the workers performing irregular tasks may be exposed to higher concentrations of hazardous substances than regular workers. It is necessary to strengthen short-term exposure measurement, even for substances which STEL have not been set.

• 한국환경보건학회지
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• 제45권4호
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• pp.370-380
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• 2019

Objective: This study was performed to investigate the distribution of individual exposure characteristics according to an exposure assessment classification for humidifier disinfectant and to identify the factors that influence assessment classification. Methods: We examined the exposure characteristics of 4,482 subjects who applied for the 4-1 and 4-2 assessments of environmental exposure to humidifier disinfectant conducted by the Korea Environmental Industry & Technology Institute (KEITI). Environmental exposure assessment classification was assessed using the following seven criteria: 1) Distance from humidifier to face; 2) Spray direction; 3) Time used, daytime 4) Time used, during sleep; 5) Time used, cumulative; 6) Exposure intensity; and 7) Cumulative exposure level. Each criteria was then classified as 'high' or low'. When participants answered for more than four criteria, exposure assessment was determined as 'definite,' 'probable,' or 'possible' depending on the ratio of 'high' responses. If participants' responses were inconsistent, exposure assessment was listed as 'unlikely.' If participants answered for less than four criteria, exposure assessment was considered 'indeterminate.' Results: For the exposure assessment classes, definite was assigned to 38.5% (1,725 subjects), probable assigned to 32.9% (1,474 subjects), 25.0% (1,122 subjects) were assigned to as possible, unlikely assigned to 0.1% (3 subjects), and indeterminate assigned to 3.5% (158 subjects). Overall, participants who used 'Oxy Ssakssak New Gaseupgi Dangbun,' 'Aekyung Gaseupgi Mate,' 'Homeplus Gaseupgi Chungjungje,' and 'E-Mart Gaseupgi Salgyunje' totaled 2,996, 557, 176, and 162 subjects, respectively. There was a statistical difference in the type of humidifier disinfectant products between high-exposed and low-exposed participants. Based on the assessment criteria of humidifier disinfectant exposure, subjects were likely to be in the highly exposed classes (definite and probable) when the subjects were exposed 1) for more than ten hours per day and 2) for more than four hours at night 3) when the total cumulative exposure time was higher than the average, 4) when the direction of humidifier spray was toward the face, 5) when the respiratory position was less than 1 meter of distance from the humidifier, 6) when the concentration of indoor contaminants (ug/m3) was higher than the average exposure intensity, and 7) when overall exposure level ($ug/m3^*hr$) was higher than the average exposure level. Conclusion: This study suggests that each exposure assessment criteria was able to appropriately estimate cumulative exposure levels.