1.Development of Korean CARcinogen EXposure: Assessment of the Exposure Intensity of Carcinogens by Industry
Dong-Hee KOH ; Ju-Hyun PARK ; Sang-Gil LEE ; Hwan-Cheol KIM ; Hyejung JUNG ; Inah KIM ; Sangjun CHOI ; Donguk PARK
Safety and Health at Work 2022;13(3):308-314
Background:
Occupational cancer is a global health issue. The Korean CARcinogen EXposure (K-CAREX), a database of CARcinogen EXposure, was developed for the Korean labor force to estimate the number of workers exposed to carcinogens by industry. The present study aimed to estimate the intensity of exposure to carcinogens by industry, in order to supply complementary information about CARcinogen EXposure intensity to the K-CAREX.
Methods:
We used nationwide workplace monitoring data from 2014 to 2016 and selected target carcinogens based on the K-CAREX list. We computed the 95th percentile levels of measurements for each industry by carcinogens. Based on the 95th percentile level relative to the occupational exposure limit, we classified the CARcinogen EXposure intensity into five exposure ratings (1–5) for each industry.
Results:
The exposure ratings were estimated for 21 carcinogenic agents in each of the 228 minor industry groups. For example, 3,058 samples were measured for benzene in the manufacturing industry of basic chemicals. This industry was assigned a benzene exposure rating of 3.
Conclusions
We evaluated the CARcinogen EXposure ratings across industries in Korean workers. The results will provide information on the exposure intensity to carcinogens for integration into the K-CAREX. Furthermore, it will aid in prioritizing control efforts and identifying industries of concern.
2.A Pilot Establishment of the Job-Exposure Matrix of Lead Using the Standard Process Code of Nationwide Exposure Databases in Korea
Ju-Hyun PARK ; Sangjun CHOI ; Dong-Hee KOH ; Dae Sung LIM ; Donguk PARK ; Hwan-Cheol KIM ; Sang-Gil LEE ; Jihye LEE ; Ji Seon LIM ; Yeji SUNG ; Kyoung Yoon KO
Safety and Health at Work 2022;13(4):493-499
Background:
The purpose of this study is to construct a job-exposure matrix for lead that accounts for industry and work processes within industries using a nationwide exposure database.
Methods:
We used the work environment measurement data (WEMD) of lead monitored nationwide from 2015 to 2016. Industrial hygienists standardized the work process codes in the database to 37 standard process and extracted key index words for each process. A total of 37 standardized process codes were allocated to each measurement based on an automated key word search based on the degree of agreement between the measurement information and the standard process index. Summary statistics, including the arithmetic mean, geometric mean, and 95th percentile level (X95), was calculated according to industry, process, and industry process. Using statistical parameters of contrast and precision, we compared the similarity of exposure groups by industry, process, and industry process.
Results:
The exposure intensity of lead was estimated for 583 exposure groups combined with 128 industry and 35 process. The X95 value of the “casting” process of the “manufacture of basic precious and non-ferrous metals” industry was 53.29 μg/m3, exceeding the occupational exposure limit of 50 μg/m3. Regardless of the limitation of the minimum number of samples in the exposure group, higher contrast was observed when the exposure groups were by industry process than by industry or process.
Conclusion
We evaluated the exposure intensities of lead by combination of industry and process. The results will be helpful in determining more accurate information regarding exposure in lead-related epidemiological studies.
3.The Fever in the Emergency Department: before Versus after COVID-19
Donguk YU ; Jae Cheon JEON ; Yaerim KIM ; Uijun PARK ; Keun Tae KIM
Keimyung Medical Journal 2021;40(2):108-113
A high body temperature, i.e. fever, is a crucial vital sign, and suggests the patient’s infection or inflammation. COVID-19 has changed the lifestyle, and led to the changes in medical use behavior of febrile patients. We investigated the change in etiologies of fever in the emergency department (ED) before and after COVID-19. The medical records of patients with fever who visited the ED of a university hospital before and after the outbreak of COVID-19 in Daegu metropolitan city, South Korea. The cause of fever and its classification were carefully decided and established by agreement through a discussion among board-certified clinicians in emergency medicine, neurology, general surgery, and internal medicine. The etiology of fever and its prevalence in ED were compared between before and after COVID-19. A total of 3,041 patients with fever (> 37.7°C) in the ED were investigated, with 1,400 men (46.0%). Their mean age was 55.88 ± 20.59, and the average number of patients with fever in ED was 8.16 ± 3.94 per a day. The most common etiology before COVID-19 was respiratory system infection (n = 535, 30.5%), followed by gastrointestinal (n = 313, 17.8%) and urinary tract infection (n = 209, 11.9%). However, after COVID-19, gastrointestinal cause became the most common (n = 247, 27.3%), followed by respiratory system (n = 126, 13.9%) and urinary tract infection (n = 102, 11.3%). There has been paradigm-shifting in fever etiology in the emergency department. It is necessary to cope with the changed fever etiology in the COVID-19 era.
4.Estimation of Lead Exposure Intensity by Industry Using Nationwide Exposure Databases in Korea
Dong-Hee KOH ; Ju-Hyun PARK ; Sang-Gil LEE ; Hwan-Cheol KIM ; Hyejung JUNG ; Inah KIM ; Sangjun CHOI ; Donguk PARK
Safety and Health at Work 2021;12(4):439-444
Background:
In a previous study, we estimated exposure prevalence and the number of workers exposed to carcinogens by industry in Korea. The present study aimed to evaluate the optimal exposure intensity indicators of airborne lead exposure by comparing to blood lead measurements for the future development of the carcinogen exposure intensity database.
Methods:
Data concerning airborne lead measurements and blood lead levels were collected from nationwide occupational exposure databases, compiled between 2015 and 2016. Summary statistics, including the arithmetic mean (AM), geometric mean (GM), and 95th percentile level (X95) were calculated by industry both for airborne lead and blood lead measurements. Since many measurements were below the limits of detection (LODs), the simple replacement with half of the LOD and maximum likelihood estimation (MLE) methods were used for statistical analysis. For examining the optimal exposure indicator of airborne lead exposure, blood lead levels were used as reference data for subsequent rank correlation analyses.
Results:
A total of 19,637 airborne lead measurements and 32,848 blood lead measurements were used. In general, simple replacement showed a higher correlation than MLE. The results showed that AM and X95 using simple replacement could be used as optimal exposure intensity indicators, while X95 showed better correlations than AM in industries with 20 or more measurements.
Conclusion
Our results showed that AM or X95 could be potential candidates for exposure intensity indicators in the Korean carcinogen exposure database. Especially, X95 is an optimal indicator where there are enough measurements to compute X95 values.
5.Possibility of Benzene Exposure in Workers of a Semiconductor Industry Based on the Patent Resources, 1990–2010
Sangjun CHOI ; Donguk PARK ; Yunkyung PARK
Safety and Health at Work 2021;12(3):403-415
Background:
This study aimed to assess the possibility of benzene exposure in workers of a Korean semiconductor manufacturing company by reviewing the issued patents.
Methods:
A systematic patent search was conducted with the Google “Advanced Patent Search” engine using the keywords “semiconductor” and “benzene” combined with all of the words accessed on January 24, 2016.
Results:
As a result of the search, we reviewed 75 patent documents filed by a Korean semiconductor manufacturing company from 1994 to 2010. From 22 patents, we found that benzene could have been used as one of the carbon sources in chemical vapor deposition for capacitor; as diamond-like carbon for solar cell, graphene formation, or etching for transition metal thin film; and as a solvent for dielectric film, silicon oxide layer, nanomaterials, photoresist, rise for immersion lithography, electrophotography, and quantum dot ink.
Conclusion
Considering the date of patent filing, it is possible that workers in the chemical vapor deposition, immersion lithography, and graphene formation processes could be exposed to benzene from 1996 to 2010.
6.Possibility of Benzene Exposure in Workers of a Semiconductor Industry Based on the Patent Resources, 1990–2010
Sangjun CHOI ; Donguk PARK ; Yunkyung PARK
Safety and Health at Work 2021;12(3):403-415
Background:
This study aimed to assess the possibility of benzene exposure in workers of a Korean semiconductor manufacturing company by reviewing the issued patents.
Methods:
A systematic patent search was conducted with the Google “Advanced Patent Search” engine using the keywords “semiconductor” and “benzene” combined with all of the words accessed on January 24, 2016.
Results:
As a result of the search, we reviewed 75 patent documents filed by a Korean semiconductor manufacturing company from 1994 to 2010. From 22 patents, we found that benzene could have been used as one of the carbon sources in chemical vapor deposition for capacitor; as diamond-like carbon for solar cell, graphene formation, or etching for transition metal thin film; and as a solvent for dielectric film, silicon oxide layer, nanomaterials, photoresist, rise for immersion lithography, electrophotography, and quantum dot ink.
Conclusion
Considering the date of patent filing, it is possible that workers in the chemical vapor deposition, immersion lithography, and graphene formation processes could be exposed to benzene from 1996 to 2010.
7.Chemical Use and Associated Health Concerns in the Semiconductor Manufacturing Industry
Chungsik YOON ; Sunju KIM ; Donguk P PARK ; Younsoon CHOI ; Jihoon JO ; Kwonseob LEE
Safety and Health at Work 2020;11(4):500-508
Background:
Research on the status of many chemicals used in the semiconductor industry is needed. The purpose of this study was to describe the overall status of chemical use in the semiconductor industry in Korea and to examine it from a health perspective.
Methods:
Data on the status of chemical use and safety data sheets at 11 of 12 major semiconductor workplaces in Korea were collected. The number of chemical products and chemical constituents, quantities of chemicals, and trade secret ingredients used, as well as the health hazards were examined.
Results:
On average, 210 chemical products and 135 chemical constituents were used at the surveyed workplaces. Among all chemical products, 33% (range: 16–56%) contained at least one trade secret ingredient. Most of the trade secret ingredients were used in the photolithography process. Several carcinogens, including sulfuric acid, chromic acid, ethylene oxide, crystalline silica, potassium dichromate, and formaldehyde were also used. Only 29% (39 of 135) of the chemical constituents had occupational exposure limits, and more than 60% had no National Fire Protection Association health, safety, and reactivity ratings. Based on the aforementioned results, this study revealed the following. First, many chemical products and constituents are being used in the semiconductor industry and many products contained trade secret ingredients. Second, many products contained significant amounts of carcinogenic, mutagenic, and reproductive toxicant materials.
Conclusion
We conclude that protecting workers in the semiconductor industry against harm from chemical substances will be difficult, due to widespread use of trade secret ingredients and a lack of hazard information. The findings of the status of chemical use and the health and safety risks in semiconductor industry will contribute to epidemiological studies, safe workplace, and worker health protection.
8.Chemical Use and Associated Health Concerns in the Semiconductor Manufacturing Industry
Chungsik YOON ; Sunju KIM ; Donguk P PARK ; Younsoon CHOI ; Jihoon JO ; Kwonseob LEE
Safety and Health at Work 2020;11(4):500-508
Background:
Research on the status of many chemicals used in the semiconductor industry is needed. The purpose of this study was to describe the overall status of chemical use in the semiconductor industry in Korea and to examine it from a health perspective.
Methods:
Data on the status of chemical use and safety data sheets at 11 of 12 major semiconductor workplaces in Korea were collected. The number of chemical products and chemical constituents, quantities of chemicals, and trade secret ingredients used, as well as the health hazards were examined.
Results:
On average, 210 chemical products and 135 chemical constituents were used at the surveyed workplaces. Among all chemical products, 33% (range: 16–56%) contained at least one trade secret ingredient. Most of the trade secret ingredients were used in the photolithography process. Several carcinogens, including sulfuric acid, chromic acid, ethylene oxide, crystalline silica, potassium dichromate, and formaldehyde were also used. Only 29% (39 of 135) of the chemical constituents had occupational exposure limits, and more than 60% had no National Fire Protection Association health, safety, and reactivity ratings. Based on the aforementioned results, this study revealed the following. First, many chemical products and constituents are being used in the semiconductor industry and many products contained trade secret ingredients. Second, many products contained significant amounts of carcinogenic, mutagenic, and reproductive toxicant materials.
Conclusion
We conclude that protecting workers in the semiconductor industry against harm from chemical substances will be difficult, due to widespread use of trade secret ingredients and a lack of hazard information. The findings of the status of chemical use and the health and safety risks in semiconductor industry will contribute to epidemiological studies, safe workplace, and worker health protection.
9.An Norovirus Outbreak at a Local Festival in Chungnam Korea
Hyunah LEE ; Donguk KIM ; Seongmin PARK ; Jongjin PARK ; Hae Sung NAM ; Jinha CHOI ; Junhyuk PARK
Journal of Bacteriology and Virology 2019;49(2):81-88
Noroviruses (NoV) are the major viral pathogen causing epidemic acute gastroenteritis and outbreaks of foodborne and waterborne illness. During the local festival in Chungnam province, group food poisoning occurred outbreak by NoV infections in Jan 2019. In this study, epidemiological analysis and molecular characterization were conducted such as genotyping, phylogeny. The prevalent genotypes of food poisoning events were NoV GII.3 and GII.17, and NoV GII.3 and GII.17 isolates of this study were completely matched in nucleotide sequence comparison of capsid gene region, respectively. In underground water and stream water, various multiple genotypes of noroviruses were detected including NoV GII.3, GII.8 and GI.4 in aquatic environment of the local festival site. Among 32 worker samples, various NoVs of five genotypes (GI.7, GI.8, GII.3, GII.8, GII.17) were detected in 12 samples and expected to causing NoV contaminated by exposure to groundwater. NoV genotype GII.3, which was detected from groundwater 2, was completely consistent with that of patients and workers. Therefore, groundwater within the local festival site could be main cause of food poisoning event. Because NoV outbreaks are caused by fecal to oral transmission, proper management of sewage purification facilities, groundwater and sanitary toilets is required for many visitors, and efforts are needed to maintain clean environment.
Base Sequence
;
Capsid
;
Chungcheongnam-do
;
Disease Outbreaks
;
Epidemiologic Studies
;
Foodborne Diseases
;
Gastroenteritis
;
Genotype
;
Groundwater
;
Holidays
;
Humans
;
Korea
;
Norovirus
;
Phylogeny
;
Rivers
;
Sewage
;
Water
10.Estimates of the Prevalence, Intensity and the Number of Workers Exposed to Cigarette Smoking across Occupations and Industries in Korea
Hyejung JUNG ; Dong Hee KOH ; Sangjun CHOI ; Ju Hyun PARK ; Hwan Cheol KIM ; Sang Gil LEE ; Donguk PARK
Journal of Korean Medical Science 2019;34(31):e213-
BACKGROUND: Tobacco smoking affects the incidence of various illnesses such as lung cancer, respiratory diseases, and cardiovascular diseases. In an effort to prevent smoking-related cancers, we aimed to estimate the smoking prevalence, intensity, and number of workers exposed to smoking, which would be specific to the occupational and industrial circumstances in Korea. METHODS: We used the Korean Working Condition Survey (KWCS) and Korea's Census data. Smoking prevalence and intensity were estimated using the KWCS data. The number of smokers was estimated by multiplying smoking prevalence with the number of workers in the occupation or industry. Smoking prevalence, intensity, and number of smokers were estimated for major, sub-major, and minor groups of occupation and industry. RESULTS: Of the total labor force in 2010, 52.66% of men and 5.24% of women workers were estimated to be current smokers. Men workers smoked 15.42 cigarettes/day, and women workers 11.29 cigarettes/day. In terms of occupation, “craft and related trades workers” demonstrated the highest smoking prevalence (52.24%). “Managers” smoked the highest number of cigarettes (16.63 cigarettes/day) and “equipment, machine operating, and assembling workers” comprised the largest number of estimated smokers (1,368,726 workers). In terms of industry, “mining and quarrying” had the highest smoking prevalence (69.27%). Those in “construction” smoked the highest number of cigarettes (17.16 cigarettes/day) and those in “manufacturing” comprised the largest number of estimated smokers (1,629,893 workers). CONCLUSION: Our results may help in setting priorities for smoking prevention-related activities. In addition, these results can be used for epidemiological studies controlling for the effect of smoking by occupation or industry.
Cardiovascular Diseases
;
Censuses
;
Employment
;
Epidemiologic Studies
;
Female
;
Humans
;
Incidence
;
Korea
;
Lung Neoplasms
;
Male
;
Occupations
;
Prevalence
;
Smoke
;
Smoking
;
Tobacco Products

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