• Asian Pacific Journal of Cancer Prevention
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• 제14권2호
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• pp.1083-1087
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• 2013

Background: Colorectal cancer has several modifiable behavioural risk factors but their relationship to the risk of colon and rectum cancer separately and between countries with high and low incidence is not clear. Methods: Data from participants in the Asia Pacific Cohort Studies Collaboration (APCSC) were used to estimate mortality from colon (International Classification of Diseases, revision 9 (ICD-9) 153, ICD-10 C18) and rectum (ICD-9 154, ICD-10 C19-20) cancers. Data on age, body mass index (BMI), serum cholesterol, height, smoking, physical activity, alcohol and diabetes mellitus were entered into Cox proportional hazards models. Results: 600,427 adults contributed 4,281,239 person-years follow-up. The mean ages (SD) for Asian and Australia/New Zealand cohorts were 44.0 (9.5) and 53.4 (14.5) years, respectively. 455 colon and 158 rectum cancer deaths were observed. Increasing age, BMI and attained adult height were associated with increased hazards of death from colorectal cancer, and physical activity was associated with a reduced hazard. After multiple adjustment, any physical activity was associated with a 28% lower hazard of colon cancer mortality (HR 0.72, 95%CI 0.53-0.96) and lower rectum cancer mortality (HR 0.75, 95%CI 0.45-1.27). A 2cm increase in height increased colon and all colorectal cancer mortality by 7% and 6% respectively. Conclusions: Physical inactivity and greater BMI are modifiable risk factors for colon cancer in both Western and Asian populations. Further efforts are needed to promote physical activity and reduce obesity while biological research is needed to understand the mechanisms by which they act to cause cancer mortality.

• 자원환경지질
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• 제38권3호
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• pp.237-245
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• 2005

중금속으로 오염된 산성 지하수의 현장 정화방법으로 투수성반응벽체 기술의 적용 가능성을 평가하기 위하여 반응매질 선정을 위한 실내실험을 수행하였다. 처리대상 오염지하수로 이용한 임기광산 폐석적치장 침출수는 낮은 pH와 높은 금속농도를 갖는다(산도부하량으로 65 kg $CaCO_3$/일, 금속부하량(Fe+Al+Mn)으로 11.6kg/일). 이러한 특성의 오염지하수는 반응매질로 유기탄소 혼합물을 이용하여 황산염환원 반응에 의한 처리가 가능할 것으로 판단된다. 다섯 가지 서로 다른 배합비를 갖는 버섯퇴비, 소나무 바크, 석회석의 혼합 반응매질을 이용한 배치실험 결과를 통해 보면 투수성반응벽체를 적용할 경우 산도부하량은 12.3kg $CaCO_3$/일, 금속부하량은 3.3kg/일로 줄일 수 있다. 대상 지하수의 낮은 pH와 높은 금속부하량을 고려하여 무기탄소를 위주로 한 완충용 반응벽체를 먼저 두고, 이어서 유기탄소 혼합물로 구성되는 반응벽체로 황산염 환원을 유도하는 방법 적용한다면 보다 효과적인 광산배수에 대한 정화를 기대할 수 있을 것이다.

• 자원환경지질
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• 제53권6호
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• pp.781-792
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• 2020

망간단괴, 망간각, 해저열수광상 개발에서 필연적으로 발생하게되는 선광잔류물은 방대한 양과 잠재적인 독성으로 인해 관심이 증가하고 있지만, 아직까지 선광잔류물의 발생량, 물리·화학적 특성, 환경 유해성, 해양생태계에 미치는 영향 등에 관한 정보가 부족한 실정이다. 최근에는 선광잔류물의 친환경적인 처리 중요성이 인식되고, 그에 따른 저감/처리법이 강구되고 있다. 심해저 광물자원개발 시 선광잔류물이 선상에서 처리되지 못할 경우, 선광잔류물의 육상으로 운반 비용이 발생하고 육상 환경오염 문제를 해결해야하는 경우가 발생하게 된다. 따라서, 한국해양과학기술원에서는 1) 오염인자/환경영향, 2) 환경/생물 위해성 영향, 3) 입자 확산, 4) 선광, 5) 저감/처리(정화)를 친환경적인 선상에서의 선광잔류물 처리를 위한 주요 핵심 요소로 구분하여 선광잔류물의 유해성, 해양생태계에 미치는 영향, 오염 입자 확산 모델, 선광 및 정화처리 후보기술 등에 대한 연구를 수행하고 있다. 본 연구 결과는 향후 심해저광물자원 개발과정에서 발생할 수 있는 환경영향에 대한 과학적인 증거 확보를 통해 환경문제를 최소화 할 수 있는 연구 기반을 제시할 수 있고, 이는 다른 기원의 오염물 및 규제없이 방치되고 있는 육상 폐광산의 누출수 처리에도 적용할 수 있을 것이라 기대한다.

• 한국환경보건학회지
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• 제49권2호
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• pp.108-117
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• 2023

Background: When particles are absorbed into the human body, they penetrate deep into the lungs and interact with the tissues of the body. Heavy metals in PM_2.5 can cause various diseases. The main source of PM_2.5 emissions in South Korea's atmosphere has been surveyed to be places of business. Objectives: The concentration of heavy metals in PM_2.5 near the Ulsan Industrial Complex was measured and a health risk assessment was performed for residents near the industrial complex for exposure to heavy metals in PM_2.5. Methods: Concentrations of heavy metals in PM_2.5 were measured at four measurement sites (Ulsan, Mipo, Onsan, Maegok) near the industrial complexes. Heavy metals were analyzed according to the Air Pollution Monitoring Network Installation and Operation Guidelines presented by the National Institute of Environmental Research. Among them, only five substances (Mn, Ni, As, Cd, Cr⁶⁺) were targeted. The risk assessment was conducted on inhalation exposure for five age groups, and the excess cancer risk and hazard quotient were calculated. Results: In the risk assessment of exposure to heavy metals in PM_2.5, As, Cd, and Cr⁶⁺ exceeded the risk tolerance standard of 10^-6 for carcinogenic hazards. The highest hazard levels were observed in Onsan and Mipo industrial complexes. In the case of non-carcinogenic hazards, Mn was identified as exceeding the hazard tolerance of 1, and it showed the highest hazard in the Ulsan Industrial Complex. Conclusions: This study presented a detailed health risk from exposure to heavy metals in PM_2.5 by industrial complexes located in Ulsan among five age groups. It is expected to be utilized as the basis for preparing damage control and industrial emission reduction measures against PM_2.5 exposure at the Ulsan Industrial Complex.

• Toxicological Research
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• 제20권2호
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• pp.89-100
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• 2004

The comet assay (also called the single-cell gel electrophoresis assay) has been widely used for detecting DNA damage and repair in individual cells. Since the conventional methods of evaluating comet assay data using frequency statistics are unsatisfactory we developed a new quantitative measure of DNA damage/repair that is based on all information residing in the dose/time-response curves of a comet experiment. Blood samples were taken from 25 breast cancer patients before undergoing radiotherapy. The comet assay was performed under alkaline conditions using isolated lymphocytes. Tail DNA, tail length, tail moment and tail inertia of the comet were measured for each patient at four doses of $\gamma$-rays (0, 2, 4 and 8 Gy) and at four time points after irradiation (0, 10, 20 and 30 min) using 100 cells each. The resulting three-dimensional dose-time response surface was modeled by multiple regression, and the second derivative, termed 2D, on dose and time was determined. A software module was programmed in SAS/AF to compute 2D values. We applied the new method successfully to data obtained from cancer patients to be assessed for their radiation sensitivity. We computed the 2D values for the four damage measures, i.e., tail moment, tail length, tail DNA and tail inertia, and examined the pairwise correlation coefficients of 2D both on the log scale and the unlogged scale. 2D values based on tail moment and tail DNA showed a high correlation and, therefore, these two damage measures can be used interchangeably as far as DNA repair is concerned. 2D values based on tail inertia have a correlation profile different from the other 2D values which may reflect different facets of DNA damage/repair. Using the dose-time response surface, other statistical models, e.g., the proportional hazards model, become applicable for data analysis. The 2D approach can be applied to all DNA repair measures, Le., tail moment, tail length, tail DNA and tail inertia, and appears to be superior to conventional evaluation methods as it integrates all data of the dose/time-response curves of a comet assay.

• 방사선산업학회지
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• 제7권2_3호
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• pp.155-159
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• 2013

Late effects of chronic exposure to gamma radiation are potential hazards to worker in radiation facilities as well as to the general public. Recently, chronic gamma radiation exposure effects have become a serious concern. Using a total of 60 mice, we studied the biological effects of medium-dose chronic exposure to gamma radiation. Sixty female 6-week-old specific pathogen free Balb/c mice were randomly divided into six groups (five groups irradiated and one non-irradiated control group). Irradiation was carried out for 7 days using gamma rays at dose rates of 119.65, 238.10, 357.14, 476.19 and $595.24mGy\;h^{-1}$ with total doses 20, 40, 60, 80 and 100 Gy. After irradiation, we determined survival rate of gamma radiation exposed mice during 1 week and 476.19 and $595.24mGy\;h^{-1}$ exposed group mice showed less 10% of survival rate. Otherwise, 119.65, 238.10 and $357.14mGy\;h^{-1}$ exposed group mice were survived each 100%, 80% and 70%. Half of survived mice after 1 week are immediately sacrifice and counted body and spleen weights. Compared with control non-irradiated group, total body weights and spleen weights isolated from 119.65, 238.10 and 357.14 irradiated group mice showed significant decreased. However, no significant alteration was observed between 119.65, 238.10 and $357.14mGy\;h^{-1}$ irradiated group. Overall, our results show for the first time that medium-dose chronic gamma radiation has the potential to stimulation of biological effects.

• 화약ㆍ발파
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• 제29권2호
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• pp.59-66
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• 2011

자연적, 기술적, 생물학적 재해에 의해 유발된 다양한 리스크가 조직의 업무연속성에 위협을 미친다. 업무연속성은 모든 조직에 가장 중요한 과제로써 그것을 적절히 관리하는 것은 조직의 성패를 가르게 된다. 업무연속성계획(BCP)은 업무연속성을 담보할 수 있는 관리 절차로 정의될 수 있다. BCP는 리스크관리, 상시운영계획, 재난대응/복구, 훈련/학습, 위기 전달 등을 포함한다. 이중에서 리스크관리는 리스크확인, 분석, 평가 처리를 하기 위한 체계적 방법으로 리스크평가는 리스크확인, 분석, 평가로 구성된다. 리스크평가는 BCP를 계획하기 위한 첫 번째 단계이다. 본 연구에서는 하수관거 매설 공사에 대해서 리스크평가를 수행하였다. 리스크평가 과정을 통해 건설 공사에 위협을 주는 18개의 리스크를 확인하였고 이들에 대한 리스크 수준 분석을 통해 대책이 필요한 가장 상위 수준의 리스크로는 '굴착면의 붕괴', '지중매설물 파손', '소음 및 먼지날림', '원자재값 상승'으로 나타났다.

• 한국산학기술학회논문지
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• 제15권7호
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• pp.4310-4317
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• 2014

본 연구는 수작업 떡류의 HACCP(Hazard Analysis Critical Control Point)시스템 적용을 위한 목적으로 하였다. 본 실험에 사용된 시료는 떡의 주원료, 작업장 시설, 도구와 작업자는, 2012년 9월 12일~2013년 2월 13일까지 서울시 용산구 서계동 소재에 있는 KB 업체에서 제공받았다. 제조공정도는 일반적인 떡류 제조업체의 제조공정을 참고로 작성하였다. 제조 공정도는 원료 농산물(맵쌀, 찹쌀, 잣 등), 부재료(분말원료), 용수와 포장재료의 입고, 보관, 정선 및 계량, 세척, 불림, 탈수, 분쇄, 주재료 혼합, 익반죽, 수작업 성형, 증자, 냉각, 절단, 내포장, 금속검출, 외포장, 보관 및 출하공정으로 작성하였다. 원료 농산물의 미생물학적 위해요소 분석결과는 Table 1과 같다. 본 연구결과 증자공정 후의 떡과 원재료의 미생물검사 결과는 안전한 것으로 보인다. 하지만, 체계적인 세척 및 소독을 실시하여 미생물학적 위해를 감소시키고 작업자 위생교육 등을 통하여 개인위생개념 향상과 작업장의 미생물 관리가 함께 이루어져야 할 것으로 여겨진다.

• Safety and Health at Work
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• 제8권3호
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• pp.237-245
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• 2017

Background: Solar furnaces are used worldwide to conduct experiments to demonstrate the feasibility of solar-chemical processes with the aid of concentrated sunlight, or to qualify high temperature-resistant components. In recent years, high-flux solar simulators (HFSSs) based on short-arc xenon lamps are more frequently used. The emitted spectrum is very similar to natural sunlight but with dangerous portions of ultraviolet light as well. Due to special benefits of solar simulators the increase of construction activity for HFSS can be observed worldwide. Hence, it is quite important to protect employees against serious injuries caused by ultraviolet radiation (UVR) in a range of 100 nm to 400 nm. Methods: The UV measurements were made at the German Aerospace Center (DLR), Cologne and Paul-Scherrer-Institute (PSI), Switzerland, during normal operations of the HFSS, with a high-precision UV-A/B radiometer using different experiment setups at different power levels. Thus, the measurement results represent UV emissions which are typical when operating a HFSS. Therefore, the biological effects on people exposed to UVR was investigated systematically to identify the existing hazard potential. Results: It should be noted that the permissible workplace exposure limits for UV emissions significantly exceeded after a few seconds. One critical value was strongly exceeded by a factor of 770. Conclusion: The prevention of emissions must first and foremost be carried out by structural measures. Furthermore, unambiguous protocols have to be defined and compliance must be monitored. For short-term activities in the hazard area, measures for the protection of eyes and skin must be taken.

• 대한의용생체공학회:의공학회지
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• 제28권6호
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• pp.811-816
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• 2007

The social activities of the elderly have been increasing as our society progresses toward an aging society. As their activities are increased, the occurrence of falls that could lead to fractures are increased. Falls are serious health hazards to the elderly and we need more thorough understanding of falls including the progress of falls and the impact area in various fall directions. Many of the traditional methods of falls research dealt with voluntary falls by younger subject since older subject can easily get fracture from voluntary falls. So, it has been difficult to get exact data about falls of the elderly. Here, we tried to capture the characteristics of the movements of major joints using three dimensional motion capture system during falls experiments using a moving mattress that can safely induce unexpected falls. Healthy younger subjects participated in the actual falls experiment and the moving mattress was actuated by a pneumatic system. The kinematic parameters such as velocities and accelerations of major segments were imported to a computer simulation environment and falls to hard surfaces were simulated in a computational environment using a realistic human model of aged persons. The simulation was able to give approximations to contact forces which can occur during actual falls.