• Journal of Radiation Protection and Research
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• v.27 no.1
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• pp.21-26
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• 2002

For the consideration of the influence on radioactive contamination of foods due to rain during the release period of radionuclides in a nuclear accident, the previous dynamic food chain model was improved. Wet interception coefficients for the agricultural plants were derived as a function of radionuclide and rainfall amount, and mathematical formula of the model was also re-established. In the results for the same time-integrated radioactive concentrations on the ground, radioactive contamination of foods decreased greatly by rainfall, and it decreased dramatically according to increasing rainfall amount. It means that predictive contamination in foods using the previous dynamic food chain model, in which dry interception to the agricultural plants is only considered, can be overestimated. Among radionuclides considering in this study ($^{137}Cs,\;^{90}Sr,\;^{131}I$), influence of rainfall for food contamination was the most sensitive to $^{131}I$, and the least sensitive to $^{90}Sr$.

• Journal of Soil and Groundwater Environment
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• v.9 no.1
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• pp.12-27
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• 2004

The contamination pattern of indoor air was simulated when groundwater dissolving benzene was used for household activities. Indoor exposure scenario consisted of inhalation, ingestion, and dermal absorption. Physiologically based pharmacokinetic (PBPK) model was used to analyze how benzene exposed to human body was distributed in internal organs. Main exposure pathways contributing total internal dose were inhalation and ingestion while the contribution of dermal absorption was very small. Man showed higher exposure rate than woman due to his higher breath rate. For a short-term exposure, benzene concentration in venous blood of SPT, RPT and liver changed rapidly while slowly did in venous blood of adipose tissue at a low concentration. For a long-term exposure, woman accumulated about 2.1 times higher than man. Most of benzene exposed to human body was removed by exhalation and metabolism at lung and liver, respectively. For inhalation and ingestion, the benzene removals by exhalation were 69.8 and 48.4%, respectively. Relative importance of removal mechanism was different according to the inflow displacement of benzene. The results obtained from this study would help understand exposure, distribution, and removal phenomena and make plans for the reduction of the health risk associated with the contaminated groundwater by various organic compounds.

• The Journal of Engineering Geology
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• v.28 no.3
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• pp.411-429
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• 2018

Daeyoung mine (also called "Daema mine") produced gold and silver from mainly gold- and silver-bearing quartz veins. The mine tailings are a waste hazard, but most of the tailings were swept away or dispersed throughout the area around the mine long before the tailing dump areas were transformed into agricultural land. Soil liner and protection facilities, such as retaining walls, were constructed in the mine area to prevent the loss of tailings. The content of the tailings is 3,424.41~3,803.61 mg/kg, which exceeds the safety standard by a factor of 45. In addition, contamination was detected near agricultural areas and in the sediments in downstream drainage channels. A high level of As contamination was concentrated near the waste tailings yard; comparaable levels were detected in agricultural areas close to streams that ran through the waste dump yard, whereas the levels were much lower in areas far from the streams. The contamination in stream sediments showed a gradual decrease with distance from the mine waste yard. Based on these contamination patterns, we concluded that there are two main paths that affect the spread of contaminants: (1) loss of mine waste, and (2) the introduction of mine waste into agricultural areas by floods after transportation by streams. The agricultural areas contaminated by mass inflow of mine waste can act as contamination sources themselves, affecting other agricultural areas through the diffusion of contaminants. At present, although the measured effect in minimal, sediments in streams are contaminated by exposed mine waste and surface liners. It is possible for contaminants to diffuse or spread into nearby areas if heavy elements trapped in soil grains in contaminated agricultural areas leach out as soil solution or contaminant particles during diffusion into the water supply.

• Journal of Radiation Protection and Research
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• v.19 no.3
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• pp.209-221
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• 1994

In the case of a severe accident of a nuclear power plant, the whole body dose and the relative importance of the radionuclides during the lifetime of an exposed person were estimated for each exposure pathway with distances from the release point. The external exposure pathways due to immersion of radioactive cloud and deposition of radioactive materials on the ground, and the internal exposure pathways due to inhalation and ingestion of contaminated foodstuffs were considered. The effects due to the ingestion of contaminated foodstuffs were estimated considering the variation of radioactive concentration in the foodstuffs according to deposition time and elapsed time after deposition using a dynamic ingestion pathway model applicable to Korean environment, named 'KORFOOD'. As the results up to 80 km from the release point, the effects due to ingestion of contaminated foodstuffs showed the highest contribution to total exposure dose. The contribution of I isotopes was the highest in the case of the external dose due to immersion of radioactive cloud and internal dose due to inhalation. The contribution of Cs isotopes was highest in the case of the external dose due to deposition of radioactive materials on the ground. In the case of the internal dose due to ingestion of contaminated foodstuffs, Cs deposition in summer and Sr deposition in winter, respectively, were the most dominant radionuclide to whole body.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.11
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• pp.619-630
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• 2015

This study was conducted to propose the methodology of human risk assessment specialized to domestic mine areas and to quantify the human risk of heavy metal (As, Cd, Cu, Pb, and Zn) contamination around two abandoned metal mines. To attain the goals, we established a relevant exposure scenario, including 7 exposure pathways and extracted a variety of exposure factors reflecting the characteristics of inhabitants around abandoned metal mine areas. Finally, carcinogenic and non-carcinogenic risks were compared between two areas, exposure pathways, heavy metal contaminants, and receptors. The total excess carcinogenic risks of two mine areas of concern were calculated to be larger than the acceptable carcinogenic risk ($1{\times}10^{-6}$), indicating those two areas are not safe for carcinogenic hazard. In addition, the hazard indices of two areas were computed to be higher than unit risk (1), suggesting that the areas of concern have non-carcinogenic risk. Ingestion of crop and intake of groundwater were evaluated to be main exposure pathways contributing to carcinogenic and non-carcinogenic risks within the areas. Also, the results show that carcinogenic and non-carcinogenic hazards were mostly attributed to As and As, Cd, and Pb, respectively.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2002.04a
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• pp.155-158
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• 2002

질산성질소 및 탁도로 오염된 지하수공에 대하여 환경성 복원을 위한 오염방지 시설을 시범 설치하였다. 지하수공에 대한 오염 정도를 조사한 결과 PS-1, CW-1, 그리고 CW-2 공이 질산성질소로 오염되어 먹는물 수질기준을 초과하였고, CW-3 공은 탁도가 먹는물 수질기준을 초과하였다. 오염원은 지하수공 개발시 수량 확보를 위하여 그라우팅을 제대로 하지 않은 불량시공으로 인한 오염된 지표수의 유입으로 기인되었다. 금번 연구는 오염된 지하수의 환경성 복원을 위한 것으로, 오염원과 지하수를 격리시켜 오염물질의 지하수 내 유입을 방지할 수 있도록 패커 그라우팅을 완벽하게 다시 실시하였으며, 오염방지시설을 설치하였다. 이 연구를 위하여 먼저 대수층의 분포 및 특성팍악, 지하수공내 지표수의 유입구간 규명, 지하수 오염원, 오염실태, 오염경로 등을 파악하였다 오염방지시설을 설치한 후, 설치 전,후의 질산성질소와 탁도의 함량을 비교하기 위하여 수질 분석을 실시하였다. PS-1의 경우, 오염방지시설 설치전의 질산성질소 함량은 16.1 mg/L 이었으나, 설치후에는 8.1 mg/L, 7.9 mg/L로써 설치전에 비하여 51% 감소되었으며, CW-1은 10.3 mg/L에서 6.3mg/L으로 39%, 그리고 CW-2는 14.9 mg/L에서 9.0 mg/L 으로 40% 감소되었다. CW-3 공의 탁도는 157 NTU에서 0.97 NTU로 완벽하게 복원되었다.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.191-192
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• 2003

원자력시설의 사고시 대기중으로 누출된 방사성물질에 의해 오염된 토양으로부터 재배된 농작물로 인한 인체노출은 각종 환경오염물질에 의한 인체영향 연구결과에 보듯이 직접적인 방사능에 의한 인체노출 못지 않게 상당히 중요하다. 이러한 섭식경로를 통한 노출은 각 나라마다 서로 다른 토양조건 및 작물체종류의 다양성등 다른 양상을 보이고 있어, 연구가 수행된 미국이나 유럽등지의 평가방법을 그대로 사용하면 국내의 토양에서 재배되는 농작물이나 이를 이용한 축산물에 따른 한국인의 독특한 섭취양상을 충분히 고려하여 평가하기 어려울 수 있다. (중략)

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2001.11a
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• pp.235-236
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• 2001

전 세계적으로 진행되고 있는 경제성장에 따른 급속한 산업발달은 인류에게 문명의 이기를 제공해 주고 있으나, 이에 수반하여 다양하고 새로운 오염물질(Bioaerosol)이 발생하고 있다. 이러한 새로운 오염 물질의 문제점은 그 피해 정도가 확실히 규명된 것이 아니라는 데 있으며, 또한 여러 경로를 통하여 오염될 수 있다는 데 있다. (중략)

• KOREAN POULTRY JOURNAL
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• v.15 s.164
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• pp.126-131
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• 1983

식중독은 단체급식소에서 주로 발생하여 많은 사람들에게 피해를 준다. 이를 예방하기 위해서는 식품을 저온 보존하여 세균증식을 억제하고, 식품취급을 위생적으로 하여 오염 경로를 차단하는 것이 중요하다.

• Air Cleaning Technology
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• v.26 no.2
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• pp.24-30
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• 2013