• 한국환경보건학회지
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• 제44권4호
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• pp.301-314
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• 2018

Objectives: The aim of this study was to introduce the overall progress of exposure assessment to humidifier disinfectant (HD); to present participants' demographic characteristics, exposure characteristics to humidifier disinfectant, and exposure classification; and furthermore to compare those characteristics between survivors and non-survivors. Methods: An assessment of environmental exposure to HD was conducted using modified HD-specific questionnaires that had been previously validated. We analyzed the data from 4,482 participants who had been potentially exposed to HD and had registered with the KEITI (Korea Environmental Industry & Technology Institute) from September 2016 to May 2018 (the fourth survey). Environmental exposure assessments were performed as follows: 1) contact with participants, 2) environmental exposure assessment though face-to-face interviews, 3) assessment review and coding, and 4) exposure rating. Results: Overall, survivors made up 77.1% (3,457 subjects) and non-survivors made up 22.9% (1,025 subjects). When compared with the survivors, non-survivors had a higher proportion of subjects aged >60 years and subjects who answered as suffering lung damage and having purchased HD because it is "Beneficial to health" (p<0.05). For the exposure characteristics compared to survivors, non-survivors had a higher proportion of cases of distance from humidifier to face being less that one meter and the spray direction being toward the face (p<0.05). Overall, respondents who used the "Oxy Ssak Ssak New Gaseupgi Dangbun", "Aekyung Gaseupgi Mate", "Homeplus Gaseupgi Chungjungje", and "E-Mart Gaseupgi Salgyunje" products made up 66.1, 12.3, 4.0, and 3.6%, respectively, and 72.5% of respondents used products with PHMG as the active chemical. When compared with survivors, non-survivors had a higher proportion of use of "Oxy Ssak Ssak New Gaseupgi Dangbun" but a lower proportion of use of products with CMIT/MIT, PGH, or PHMG as the active chemical. Conclusions: This study provided demographic characteristics and exposure assessment for applicants who have been injured by HD. In spite of the limitations of performing past exposure assessment through a questionnaire survey, such as recall bias, useful results may be obtained by comparing survivors with non-survivors. Further studies such as the exposure rating method and so on are necessary to assess past exposure to HD.

• 한국산업보건학회지
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• 제17권4호
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• pp.310-321
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• 2007

Status of benzene exposure was evaluated upon petrochemical workers in the Yeosu Industrial Complex, based on questionnaire responses by workers, review of previous work environment assessment reports between 1996 and 2004, in addition to short-term exposure measurements for unit tasks in the field. Questionnaire results showed that workers in the field were suffering concern on and symptoms of respiratory diseases, cancers or other illnesses of unknown causes. In particular, workers were highly worried about the risk of exposure to chemical hazards including benzene, while conducting specific tasks (e.g. sampling, draining, gauging) among normal operations during which equipments are opened and contents are exposedin the air, as well as periodic turnaround (TA) task. However, the review of previous work environment assessment reports found out that short-term exposure assessment data for unit tasks accounted for less than 1% of total data, and most of them were on 8-hr average exposure level. It also turned out that benzene was not detected in 83% of total samples, suggesting routine but pointless sampling has been repeated. Short-term exposure level was assessed focusing on tasks with high level of complaints on the exposure risk, based on the questionnaire responses. As predicted, a maximum of 741 ppm benzene exposure was reached depending on types and conditions of operations involved. In conclusion, these findings suggest that the evaluation and management on the short-term high exposure tasks including turnaround are crucial in reducing benzene exposure and preventing haematopoietic cancer in workers in the petrochemical industry.

• Environmental Analysis Health and Toxicology
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• 제30권
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• pp.5.1-5.8
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• 2015

Objectives We aimed to assess the radiation exposure for epidemiologic investigation in residents exposed to radiation from roads that were accidentally found to be contaminated with radioactive cesium-137 ($^{137}Cs$) in Seoul. Methods Using information regarding the frequency and duration of passing via the $^{137}Cs$ contaminated roads or residing/working near the roads from the questionnaires that were obtained from 8875 residents and the measured radiation doses reported by the Nuclear Safety and Security Commission, we calculated the total cumulative dose of radiation exposure for each person. Results Sixty-three percent of the residents who responded to the questionnaire were considered as ever-exposed and 1% of them had a total cumulative dose of more than 10 mSv. The mean (minimum, maximum) duration of radiation exposure was 4.75 years (0.08, 11.98) and the geometric mean (minimum, maximum) of the total cumulative dose was 0.049 mSv (<0.001, 35.35) in the exposed. Conclusions An individual exposure assessment was performed for an epidemiological study to estimate the health risk among residents living in the vicinity of $^{137}Cs$ contaminated roads. The average exposure dose in the exposed people was less than 5% of the current guideline.

• 한국산업보건학회지
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• 제26권2호
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• pp.219-224
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• 2016

Objectives: Lung cancer occurred with worker working in an urban bus garage. A survey was conducted to investigate whether lung cancer had causal relationship with work. Exposure to asbestos and diesel engine exhaust were suspected. Methods: Airborne asbestos was sampled on membrane filter and analyzed using phase-contrast microscopy. Airborne diesel exhaust was sampled using quartz filter and analyzed with thermal-optical analyzer. Polynuclear aromatic hydrocarbons was sampled using PTFE filter and XAD-2 tube and analyzed with gas chromatography-mass selective detector. Results: Airborne asbestos concentration was under 0.01 fiber/cc. Worker who warmed up an engine of urban bus for 2 hours was exposed to elemental carbon concentration, $15.5{\mu}g/m^3$. Only naphtalene among polynuclear aromatic hydrocarbons was detected. Conclusions: It was difficult to conclude about worker exposure to asbestos because working hour related asbestos was too short. In reviewing papers, the exposure to asbestos over 0.01 fiber/cc during exchange brake lining was found. It was identified that worker's occupational exposure to diesel exhaust based on elemental carbon was higher than the other occupational exposure to diesel exhaust.

• 한국산업보건학회지
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• 제25권2호
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• pp.146-155
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• 2015

Objectives: The aims of this study were to set up benzene exposure matrices according to industry and process and to assess the risk of those occupational exposure to benzene. Methods: The benzene exposure matrices were assembled depending on industry and process, based on an exposure database provided by KOSHA(the Korean Occupational Safety and Health Agency), which was gathered from a workplace hazards evaluation program in Korea. These exposure matrices were assessed by Hallmark Risk Assessment tool. Results: The benzene was treated 412 industries sector(36%), 2,747 business places, and 471 industrial processes according to database. The arithmetic mean of past decade 8 hours time-weighted average of airborne benzene concentrations in the workplace was 0.10722 ppm. 1.07% of the total sample were greater than OEL, and 59.8% were showed less than the limit of detection. The highest risk values(Danger Value) were seen 36 industries including manufacture of general paints and similar product and 12 processes, such as other painting of manufacture of metal fabricated members. Exposure matrices based on employee exposure data base may provide exposure histories and can be used in epidemiological studies. Conclusions: It was found that more attentions should be paid to 36 among 412 industries and 12 of 471 processes, with a higher risk value.

• Toxicological Research
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• 제21권2호
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• pp.87-98
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• 2005

Human exposure to nano-sized particles (NSP) has increased over the last century with anthropogenic sources, and the rapid development of nanotechnology becomes an another source of such exposure. Information regarding the safety of nanotechnology and its product, nanoparticles, is urgently needed when assuming exposure through inhalation, oral intake, and penetration across skin is ever increasing as growing nanotechnology rapidly. The recent advancement of biokinetic studies with NSP and newer epidemiologic and toxicologic studies with ultrafine particles can be the basis for the nanotoxicology. Some concepts of nanotoxicology can be known from the results of these results. Specific small size of NSP, when inhaled, facilitates deposition by difusional mechanism in all regions of the respiratory tract and uptake into cells, ranscytosis across epithelial and endothelial cells into the blood and lymph circulation to reach target sites. Translocation along axons and dendrites of neuron makes an access to CNS and ganglia. These biokinetics are dependent on NSP surface chemistry. Risk assessments of NSP include appropriate and relevant doses/concentration selections, the increase effects in the organism and the benefits of possible desirable effects. An interdisciplinary team approach is desirable for nanotoxicology research and an appropriate risk assessment.

• 한국산업보건학회지
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• 제22권2호
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• pp.164-173
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• 2012

Objectives: Epichlorohydrin is a material that has been predicted to have high volatility and strong toxicity and is used normally in working area. Therefore, the hazardous and dangerous level and the foreign management system about epichlorohydrin should be invested at home and abroad and through hazard assessment for occupational environment measurement and exposure status of industrial workers in domestic working area. Methods: To assess risk and to suggest Development and Adoption to prevent health damage of workers owing to the epichlorohydrin exposure, the hazardousness and dangerousness of epichlorohydrin and its practical examples and regulation level for domestic and abroad health impairment are researched on the base of various references. Results: The epichlorohydrin caused skin and mucus membrane irritation, respiratory paralysis, kidney and live damage under the influence of acute toxicity and in animal study, it was confirmed as a doubtful carcinogenic substance to trigger reducement of sperm number and reproduction ability, abnormal spermatogenesis, mutagen, increase of forestomach epithelium and occurrence of papilloma and so on, as well as it induced stimulus asthma and allergic contact dermatitis for exposure workers. Conclusions: Epichlorohydrin was found to occur allergic contact dermatitis, carcinogenesis doubt and reproduction toxicity and was verified as a material which would be established reinforcement of management level to care health of handlers, such as denotement dangerousness of skin absorption.

• 대한예방의학회:학술대회논문집
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• 대한예방의학회 1994년도 교수 연수회(환경)
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• pp.651-657
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• 1994

To assess quantitatively the association between benzene exposure and leukemia, we examined the mortality rate of a cohort with occupational exposure to benzene. Cumulative exposure for each cohort member was estimated from historical air-sampling data and, when no sampling data existed, from interpolation on the basis of existing data. The overall standardized mortality ratio (a measure of relative risk multiplied by 100) for leukemia was 337 (95 percent confidence interval, 154 to 641), and that for multiple myeloma was 409 (95 percent confidence interval, 110 to 1047). With stratification according to levels of cumulative exposure, the standardized mortality ratios for leukemia increased from 109 to 322, 1186, and 6637 with increases in cumulative benzene exposure from less than 40 parts per million-years (ppm-years), to 40 to 199, 200 to 399, and 400 or more. respectively. A cumulative benzene exposure of 400 ppm years is equivalent to a mean annual exposure of 10 ppm over a 40-year working lifetime; 10 ppm is the currently enforceable standard in the United States for occupational exposure to benzene. To examine the shape of the exposure-response relation, we performed a conditional logistic-regression analysis, in which 10 controls were matched to each cohort member with leukemia. From this model, it can be calculated that protection from benzene induced leukemia would increase exponentially with any reduction in the permissible exposure limit.

• 한국소음진동공학회논문집
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• 제22권10호
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• pp.940-948
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• 2012

In Korea, researches on the exposure assessment of the hand-transmitted vibration started from the mid-90, however, they were performed in the limited industries such as auto-assembly plants and the evaluation of the vibration was mostly conducted by ISO 5349(1986). Therefore, it was necessary to assess hand-transmitted vibration levels of workplace such as ship building/repairing industry or mining industry where occupational injuries are largely occurred and to evaluate the vibration levels using revised ISO 5349(2001). The SVAN 948 Four Channels Sound & Vibration Analyser was used for the measurement. The workers using a chain saw were exposed to 1.7~2.8 $m/s^2$ of daily vibration level. Workers using a rock drill in a coal mining were exposed to the highest vibration acceleration among workers and the levels were 7.1~10.8 $m/s^2$. Vibration levels of grinders were different according to the types of grinders. The hand-transmitted vibration of 3 types of grinders were measured and the levels were 3.3~11.1 $m/s^2$. Workers using a impact wrench were exposed to 1.5~1.6 $m/s^2$ of vibration. Out of 20 kinds of machines, only 4 tools provided the information of vibration acceleration on the instructions. In addition, the current condition of workplace to control vibration was not much different from the past because there are no vibration exposure limit.

• Safety and Health at Work
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• 제12권2호
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• pp.174-183
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• 2021

Background: Toluene diisocyanate (TDI) is a highly reactive chemical that causes sensitization and has also been associated with increased lung cancer. A risk assessment was conducted based on occupational epidemiologic estimates for several health outcomes. Methods: Exposure and outcome details were extracted from published studies and a NIOSH Health Hazard Evaluation for new onset asthma, pulmonary function measurements, symptom prevalence, and mortality from lung cancer and respiratory disease. Summary exposure-response estimates were calculated taking into account relative precision and possible survivor selection effects. Attributable incidence of sensitization was estimated as were annual proportional losses of pulmonary function. Excess lifetime risks and benchmark doses were calculated. Results: Respiratory outcomes exhibited strong survivor bias. Asthma/sensitization exposure response decreased with increasing facility-average TDI air concentration as did TDI-associated pulmonary impairment. In a mortality cohort where mean employment duration was less than 1 year, survivor bias pre-empted estimation of lung cancer and respiratory disease exposure response. Conclusion: Controlling for survivor bias and assuming a linear dose-response with facility-average TDI concentrations, excess lifetime risks exceeding one per thousand occurred at about 2 ppt TDI for sensitization and respiratory impairment. Under alternate assumptions regarding stationary and cumulative effects, one per thousand excess risks were estimated at TDI concentrations of 10 - 30 ppt. The unexplained reported excess mortality from lung cancer and other lung diseases, if attributable to TDI or associated emissions, could represent a lifetime risk comparable to that of sensitization.