• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.8 no.2
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• pp.242-253
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• 1998

South Korea has been producing asbestos over 60 years. The use of asbestos was over 50 years for production of asbestos slate and 27 years for asbestos friction materials including asbestos textile and brake-lining. Thus, it can be supposed that asbestos related diseases such as asbestosis, lung cancer and mesothelioma could be found in the vulnerable workers exposed to asbestos in 1955-1975, given the average latency period of 10-30 years. Asbestos was produced primarily by Japanese during World War II In Korea. The production of chrysotile peaked to 4,815 tons in 1944. From 1978 to 1984, 10,000 tons of asbestos were produced annually. However, the production was interrupted by raising labor costs and extinction of mine reserves, and finally they had to depend on import for the need of asbestos. In 1945, there were 16 asbestos mines, in total, with the addition of new asbestos mines in South Korea. Imports of asbestos was increased from 74,000 tons to 95,000 tons during the period of 1976 - 1992. But the imports was reduced to 88,000 tons in 1995. Since, in addition to the import of asbestos itself, the imports of asbestos products were increased as well and the accumulation of asbestos reached to 30,000 tons during the period of 1964 to 1993. In 1965, there was only one asbestos company with 207 employees. But the size of asbestos industry has been expanded so much that 118 asbestos companies could be found in 1993 with 1,476 workers. However, there was no record on the survey of asbestos concentration to which workers were exposed in any companies in 1983. The record of the air-borne concentration of the asbestos in textile working places in 1984 showed 6.7 fibers/cc by geometric mean(GM), but it was reduced to 1.2 fibers/cc in 1993. GMs of asbestos in working places for construction materials and asbestos textiles were also decreased from 1.7 fibers/cc to 0.55 fibers/cc during the period of 1984 - 1996.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.24 no.2
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• pp.113-121
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• 2014

Objectives: This study is intended to seek credible and efficient measurements on airborne asbestos concentrations that allow immediate action by establishing complementary data through comparative analysis with existing PCM and KF-100 method real-time monitoring equipment in working areas in Seoul where asbestos-containing buildings are being demolished, including living environment surroundings. Materials: We measured airborne asbestos concentrations using PCM and KF-100 at research institutes, monitoring networks, subway stations and demolition sites of asbestos-containing buildings. Through this measurement data and KF-100 performance testing, we drew a conversion factor and applied it via KF-100. Finally we verified the relationship between PCM and KF-100 with statistical methods. Results: The airborne asbestos concentrations by PCM for the objects of study were less than the detection limit(7 fiber/$mm^2$) in three (20%) out of 15 samples. The highest concentration was 0.009 f/cc. The airborne asbestos concentrations by PCM in laboratories, monitoring networks, subway stations and demolition sites of asbestos-containing buildings were respectively $0.002{\pm}0.000$ f/cc, $0.004{\pm}0.001$ f/cc, $0.009{\pm}0.001$ f/cc, and $0.002{\pm}0.000$ f/cc. As a result of KF-100 performance testson rooftops, the conversion factor was 0.1958. Applying the conversion factor to KF-100 for laboratories, the airborne asbestos concentrations ratio of the two ways was nearly 1:1.5($R^2$=0.8852). Also,the airborne asbestos concentration ratio of the two ways was nearly 1:1($R^2$=0.9071) for monitoring networks, subway stations, and demolition sites of asbestos-containing buildings. As a result of independent sample t-tests, there was no distinction between airborne asbestos concentrations monitored in the two ways. Conclusions: In working areas where asbestos-containing buildings are being demolished, including living environment surroundings, quickly and accurately monitoring airborne asbestos scattered in the air around the working area is highly important. For this, we believea mutual interface of existing PCM and a real-time monitoring equipment method is possible.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.4 no.2
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• pp.127-136
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• 1994

Diffusional sampling devices offer many advantages for measuring concentration levels of industrial contaminants than the conventional pump and charcoal tubes because they are lightweight, require no power, pump or tubing. This study designed to evaluate and compare the sampling performance of passive sampler to charcoal tube from mixed organic solvent workplace with 181 organic solvent using workers working in different concentration of organic solvents. All study workers kept both devices in their breathing zone simultaneuosly in the workplaces, and the sampling analytical results were compared with those of charcoal tube. The results obtained are as follows: 1. The concentrations of toluene and xylene measured by passive sampler were slightly higher than those of charcoal tube, but there were no significant statistical differences between two methods. 2. The concentrations of MEK and cyclo-hexanone measured by passive sampler in low exposure workplace (below 0.20 of MEK TLV levels and 0.1 of cyclo-hexanone TLV levels) were about 2 times higher than that of charcoal tube sampling. While, absorption efficiency of passive sampler was reduced according to increasing concentration measurements of MEK and cyclo-hexanone in air. 3. The ratios of concentrations of toluene, xylene, MEK and cyc1o-hexanone measured by passive sampler over those measured by charcoal tube were 1.11, 1.07, 1.63 and 3.65 respectively. 4. The percentages of concentration of passive samplers within 0.75 and 1.25 of charcoal tube value as a reference value of 1.0 were 57% in toluene, 74% in xylene, 34% in MEK and 32% in cyclo-hexanone respectively. 5. The correlation coefficients of toluene, xylene, MEK and cyclo-hexanone between passive sampler and charcoal tube sampler were 0.963, 0.957, 0.943 and 0.562 with statistical significance.

• Journal of Food Hygiene and Safety
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• v.26 no.4
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• pp.315-321
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• 2011

This study was performed to investigate contamination levels of aflatoxins, the secondary metabolites produced by fungi Aspergillus flavus and A. parasiticus, in herbal medicine. Herbs is susceptible to these fungi infections through its growth harvest, transport and storage. This study determine the aflatoxin $B_1$, $B_2$, $G_1$ and $G_2$ levels by HPLC-florescence detector coupled with photochemical enhancement in 558 samples herbal medicine distributed in Korea and China. Also, We checked a transfer ratio of aflatoxins from raw herbal medicines to herbal medicine extract. Hot water extraction of herbal medicines was prepared by air pressure and high pressure condition. The analytical method for aflatoxins was validated in this method. In results recoveries of the analytical method were ranged from 67.4% to 96.2% and, limits of detection and quantitation for aflatoxins were $0.015{\sim}0.138\;{\mu}g/kg$ and $0.046{\sim}0.418\;{\mu}g/kg$, respectively. According to the results of monitoring on aflatoxins in herbal medicine, aflatoxins 1.7 ug/kg $B_1$ and 0.9 ug/kg $G_1$ were detected in only one sample of Strychni Ignatii Semen, and 0.8 ug/kg $G_1$ in Strychni Semen. About 13.6~51.3% of aflatoxins were transferred to hot water extract. Although the detected levels are under the permitted levels for aflatoxins in herbal medicine, these amounts should be considered in regard to overall daily exposure to mycotoxins.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.9 no.1
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• pp.56-72
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• 1999

Airborne concentrations of welding fumes in which 13 different metals such as Al, Cd, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Si, Sn, Ti, and Zn were analyzed were measured at 18 factories including automobile assembly and manufactures, steel heavy industries and shipyards. Air samples were collected by personal sampler at each worker's worksite(n=339). Blood levels of Cd, Cu, Fe, Mn, Pb and Zn were also measured from samples taken from 447 welders by atomic absorption spectrometry and compared with control values obtained from 127 non-exposed workers. The results were as follows ; 1. Among various welding types, $CO_2$ welding 70.2 % were widely used, shielded metal arc welding(SMAW) 22.1 % came next, and rest of them were metal inert gas(MIG) welding, submerged arc welding(SAW), spot welding(SPOT) and tungsten inert gas(TIG) welding. 2. Welding fume concentration was $0.92mg/m^3$($0.02{\sim}15.33mg/m^3$) at automobile assembly and manufactures, $4.10mg/m^3$($0.02{\sim}70.75mg/m^3$) at steel heavy industries and $5.59mg/m^3$($0.30{\sim}91.16mg/m^3$) at shipyards, respectively, showing significant difference among industry types. Workers exposed to high concentration of welding fumes above Korean Permissible Exposure Limit(KPEL) amounted to 7.9 % and 12.5 %, in $CO_2$ welding and in SMAW at automobile assembly and manufactures and 62.7 % in $CO_2$ welding, and 12.5 % in SMAW at shipyards, and 66.2 % in $CO_2$ welding and 70.6 % in SMAW at steel heavy industries. 3. Geometric mean of airborne concentration of each metal released from welding fumes was below one 10th of KPEL in all welding types. Percentage of workers, however, exposed to airborne concentration of metals above KPEL amounted to 16.8 % in Mn and 7.6 % in Fe in $CO_2$ welding; 37.5 % in Cu in SAW, 30 % in Cu in TIG; and 25 % in Pb in SPOT welding. As a whole, 76 Workers(22.4%) were exposed to high concentration of any of the metals above KPEL. 4. There were differences in airborne concentration of metals such as Al, Cd, Cr, Cu. Fe. Mn, Mo, Ni, Pb, Si, Sn, Ti and Zn by industry types. These concentrations were higher in shipyards and steel heavy industries than in automobile assembly and manufactures. Workers exposed to higher concentration of Pb above KPEI amounted to 7.4 % of workers(7/94) in automobile assembly and manufactures. In shipyards, 19.2 % of workers(19/99) were over-exposed to Mn and 7.1 % (7/99) to Fe above KPEL. In steel heavy industries, 14.4 %(21/146), 7.5 %(11/146) and 13 %(19/146) were over-exposed to Mn, Fe and Cu, respectively. As a whole, 76 out of 339 workers(22.4%) were exposed to any of the metals above KPEL. 5. Blood levels of Cd, Cu, Fe, Mn, Pb, and Zn in welders were $0.11{\mu}g/100m{\ell}$, $0.84{\mu}g/m{\ell}$, $424.4{\mu}g/m{\ell}$, $1.26{\mu}g/100m{\ell}$, $5.01{\mu}g/100m{\ell}$ and $5.68{\mu}g/m{\ell}$, respectively, in contrast to $0.09{\mu}g/100m{\ell}$, $0.70{\mu}g/m{\ell}$, $477.2{\mu}g/m{\ell}$, $0.73{\mu}g/100m{\ell}$, $3.14{\mu}g/100m{\ell}$ and $6.15{\mu}g/m{\ell}$ in non-exposed control groups, showing significantly higher values in welders but Fe and Zn.

• Journal of Food Hygiene and Safety
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• v.25 no.4
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• pp.303-309
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• 2010

This study was planned to monitor the change in the content of sulfur dioxide during the drying process of fresh vegetables. The analysis of sulfur dioxide was conducted by the Optimized Monier-Williams Method based on the Korea Food Code. The samples were kinds of vegetables which consisted of naturally-originated sulfur compounds (green onion, onion, cabbage, garlic, radish leaves, radish). Fresh vegetables (n = 182) and dried vegetables (n = 41) purchased from different local areas were investigated for the content of sulfur dioxide. The fresh vegetables were dried at 50~$60^{\circ}C$ using hot-air dryer. The moisture contents of dried samples were adjusted to keep 10 percents. The contents of sulfur dioxide in self-dried vegetables were 104.6 mg/kg in green onion, 75.4 mg/kg in onion, 129.1 mg/kg in cabbage, 197.6 mg/kg in garlic, 23.0 mg/kg in radish leaves and 52.5 mg/kg in radish, respectively. The increase of sulfur dioxide content according to the moisture content reduction was different from the expected. It means that the contents of sulfur dioxide can be altered by other factors except moisture contents. This results can be utilized as materials for the safe management of sulfites of dried vegetables.

• Journal of Preventive Medicine and Public Health
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• v.23 no.3 s.31
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• pp.324-337
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• 1990

To assess the effectiveness of the interventions in working environment and personal hygiene for the occupational exposure to the lead, 156 workers (116 exposed subjects and 40 controls) of a newly established battery factory were examined for their blood lead concentration (Pb-B) in every 3 months up to 18 months. Air lead concentration (Pb-A) of the workplaces was also checked for 3 times in 6 months interval from August 1987. Environmental intervention included the local exhaust ventilation and vacuum cleaning of the floor. Intervention of the personal hygiene included the daily change of clothes, compulsory shower after work and hand washing before meal, prohibition of cigarette smoking and food consumption at the work site and wearing mask. Mean Pb-B of the controls was $21.97{\pm}3.36{\mu}g/dl$ at the preemployment examination and slightly increased to $22.75{\pm}3.38{\mu}g/dl$ after 6 months. Mean Pb-B of the workers who were employed before the factory was in operation (Group A) was $20.49{\pm}3.84{\mu}g/dl$ on employment and it was increased to $23.90{\pm}5.30{\mu}g/dl$ after 3 months (p<0.01). Pb-B was increased to $28.84{\pm}5.76{\mu}g/dl$ 6 months after the employment which was 1 month after the initiation of intervention program. It did not increase thereafter and ranged between $26.83{\mu}g/dl\;and\;28.28{\mu}g/dl$ in the subsequent 4 tests. Mean Pb-B of the workers who were employed after the factory had been in operation but before the intervention program was initiated (Group B) was $16.58{\pm}4/53{\mu}g/dl$ before the exposure and it was increased to $28.82{\pm}5.66{\mu}g/dl$(P<0.01) in 3 months later (1 month after the intervention). The values of subsequent 4 tests remained between 26.46 and $28.54{\mu}g/dl$. Mean Pb-B of the workers who were employed after intervention program had been started (Group C) was $19.45{\pm}3.44{\mu}g/dl$ at the preemployment examination and gradually increased to $22.70{\pm}4.55{\mu}g/dl$ after 3 months(P<0.01), $23.68{\pm}4.18{\mu}g/dl$ after 6 months, and $24.42{\pm}3.60{\mu}g/dl$ after 9 months. Work stations were classified into 4 parts according to Pb-A. The Pb-A of part I, the highest areas, were $0.365mg/m^3$, and after the intervention the levels were decreased to $0.216mg/m^3\;and\;0.208mg/m^3$ in follow-up tests. The Pb-A of part II was decreased from $0.232mg/m^3\;to\;0.148mg/m^3,\;and\;0.120mg/m^3$ after the intervention. Pb-A of part III and W was tested only after intervention and the Pb-A of part III were $0.124mg/m^3$ in Jannuary 1988 and $0.081mg/m^3$ in August 1988. The Pb-A of part IV not stationed at one place but moving around, was $0.110mg/m^3$ in August 1988. There was no consistent relationship between Pb-B and Pb-A. Pb-B of the group A and B workers in the part of the highest Pb-A were lower than those of the workers in the parts of lower Pb-A. Pb-B of the workers in the part of the lowest Pb-A incerased more rapidly. Pb-B of group C workers was the highest in part I and the lowest in part IV. These findings suggest that Pb-B is more valid method than Pb-A for monitoring the health of lead workers and intervention in personal hygiene is more effective than environmental intervention.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.6
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• pp.510-517
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• 2014

The purpose of this study was to analyze microbial hazards for cultivation environments and personal hygiene of strawberry and tomato farms at the growth and harvesting stage. Samples were collected from thirty strawberry farms and forty tomato farms located in Korea and tested for Staphylococcus aureus and Bacillus cereus. To investigate the change in the distribution of the S. aureus and B. cereus, a total of 4,284 samples including air born, soil or medium, mulching film, harvest basket, groves and irrigation water etc. were collected from eight strawberry farms and nine tomato farms for one year. As a result, total S. aureus and B. cereus in all samples were detected. Among the total bacteria of strawberry farms, S. aureus (glove: $0{\sim}2.1Log\;CFU/100cm^2$, harvest basket: $0{\sim}3.0Log\;CFU/100cm^2$, soil or culture media: 0~4.1 Log CFU/g, mulching film: $0{\sim}3.8Log\;CFU/100cm^2$), B. cereus (glove: $0{\sim}2.8Log\;CFU/100cm^2$, harvest basket: $0{\sim}4.8Log\;CFU/100cm^2$, soil or culture media: 0~5.3 Log CFU/g, mulching film: $0{\sim}4.5Log\;CFU/100cm^2$) were detected in all samples. The total bacteria of tomato farms, S. aureus (glove: $0{\sim}4.0Log\;CFU/100cm^2$, harvest basket: $0{\sim}5.0Log\;CFU/100cm^2$, soil or culture media: 0~6.1 Log CFU/g, mulching film: $0{\sim}4.0Log\;CFU/100cm^2$), B. cereus (glove: $0{\sim}4.0Log\;CFU/100cm^2$, harvest basket: $0{\sim}4.3Log\;CFU/100cm^2$, soil or culture media: 0~5.9 Log CFU/g, mulching film: $0{\sim}4.7Log\;CFU/100cm^2$) were detected in all samples. The contamination of S. aureus and B. cereus were detected in soil, mulching film and harvest basket from planting until harvest to processing, with the highest count recorded from the soil. But S. aureus and B. cereus were not detected in irrigation water samples. The incidence of S. aureus and B. cereus in hydroponics culture farm were less than those in soil culture. The amount of S. aureus and B. cereus detected in strawberry and tomato farms were less than the minimum amount required to produce a toxin that induces food poisoning. In this way, the degree of contamination of food poisoning bacteria was lower in the production environment of the Korea strawberry and tomato, but problems can be caused by post-harvest management method. These results will be used as fundamental data to create a manual for sanitary agricultural environment management, and post-harvest management should be performed to reduce the contamination of hazardous microorganisms.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.1
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• pp.438-444
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• 2015

The aim of this research was to apply a HACCP system (Hazard Analysis Critical Control Point) to fermented milk. The main ingredients of fermented milk, work facilities and workers were obtained from a company named YD, which is located in Seobuk-gu, Cheonan-si between November 5 2013 to April 13, 2014. A manufacturing process chart was prepared by referring to the manufacturing process of fermented milk manufacturers in common. The manufacturing process chart was made with raw materials; Raw milk, High Fructose Corn Syrup, Oligosaccharides, Lactic Acid bacteria and Subsidiary ingredients, Warehousing of packaging materials, Storage, Input, Preheating, Mixing, Homogeneity, Sterilization, Precooling, Culture, Filtration, In packaging, Out packaging, Storage, and Consignment, as listed Table 1. The results of the microbiological hazard analysis on the raw materials was safe after sterilization($90^{\circ}C{\pm}5^{\circ}C$, $35{\pm}3min.$) On the other hand,a microorganism test of an environment and workers suggested that the microbiological hazard should be reduced through systematic cleaning and disinfection accompanied by improved personal hygiene based on hygienic education on workers and the management of microorganisms in air.

• Journal of Environmental Health Sciences
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• v.32 no.5 s.92
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• pp.404-411
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• 2006

이 연구의 목적은 유치원에서 총 휘발성 유기화합물의 농도를 평가하고, 총 휘발성 유기화합물 농도와 대표적인 8개 방향족 화합물의 상관관계를 조사하는데 있다. 도시에 위치한 11개 유치원의 실내와 실외에서 각각 30개, 11개의 지역시료를, 시골에 위치한 4개 유치원에서는 각각 10개, 4개의 시료를 테낙스 튜브를 이용하여 오전에 1-2시간 채취하였다. 채취한 시료는 열탈착하여 가스크로마토그래피-질량분석기로 분석하였다. 13가지 물질을 각각의 표준물질로 개별 정량하여 이중 빈번히 발견되는 8가지 방향족 유기화합물은 상관관계 평가에 사용하였다. 총 휘발성 유기화합물은 톨루엔을 기준으로 정량하였다. 도시에 위치한 유치원 실내의 총 휘발성 유기화합물 농도가 높았고, 조사 건수의 50%가 환경부 및 교육인적자원부의 가이드라인($400{\mu}g/m^{3}$)을 초과하였다. 도시지역의 유치원 실내 및 실외의 기하평균은 각각 $387.9{\mu}g/m^{3}$과 $134.9{\mu}g/m^{3}$이었고, 시골지역 유치원에서는 각각 $189.6{\mu}g/m^{3},;74.4{\mu}g/m^{3}$이었다. 톨루엔, 크실렌, 에틸벤젠, 정량한 유기 화합물 총합, 총 휘발성 유기화합물은 기하정규분포를 하였다. 벤젠, 톨루엔, 에틸벤젠, 크실렌(BTEX)은 도시에 위치한 유치원에서 농도도 높고, 총 휘발성 유기화합물중 함량도 높았고, 시골지역에서는 농도와 상대적 함량이 낮았다. 도시지역에서는 총 휘발성 유기화합물 중 BTEX의 비중이 25.2%였고 정량한 13가지 유기화합물 중에서는 35.6%를 차지하였다. BTEX 각각 개별물질은 미국 환경보호청이 제시하는 일일 노출 기준량(Reference Concentration; RfC) 보다는 현저히 낮았다. 총 휘발성 유기화합물읜 농도는 실내가 실외 보다 높았다(I/O ratio 2.5). BTEX의 상대적 함량도 실내가 실외보다 높아 실내에도 발생원이 있음을 암시하고 있다. 자료 분석결과 유치원 실내의 벤젠은 실외로부터 유입되고 있었고, 톨루엔, 에틸벤젠, 크실렌은 실외뿐 아니라 실내에서도 발생하고 있었다. 정량한 8개 화합물 각각과 총 휘발성 유기화합물의 스피어만 상관계수는 벤젠을 제외하고는 모두 유의하였다. 이중 톨루엔과 크실렌은 총 휘발성 유기화합물과 좋은 상관성 (톨루엔 0.76, 크실렌, 0.87)을 나타내었다. 이 연구는 톨루엔과 크실렌이 총 휘발성 유기화합물의 좋은 지표를 사용될 있고, 톨루엔, 에틸벤젠, 크실렌 등 많은 휘발성 유기화합물의 발생원은 실외뿐 아니라 실내에도 있음을 나타내고 있다.