• Korean Chemical Engineering Research
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• 제51권6호
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• pp.745-754
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• 2013

본 연구에서는 유해원소로 오염된 현장토양을 대상으로 물리적 및 화학적 토양세척공법을 적용하였을 경우, 유해원소의 처리효율과 더불어 토양세척공법에서 발생하는 폐수를 중화, 응집, 흡착 반응을 이용하여 처리할 경우를 고려하여 최적 토양세척공법의 선정방법을 평가하고자 하였다. 본 연구에서 사용한 토양에서 주된 유해원소인 비소제거에 수산화나트륨 수용액이 황산 수용액보다 효과적이었다. 반면, 폐수 처리의 경우 수산화나트륨 수용액으로 토양 세척 시 함께 추출되는 토양유기물로 인하여 폐수처리가 복잡하고 유해원소의 제거가 잘되지 않아 세척공정의 세척제로는 산을 이용하여 토양을 세척하는 것이 좋으며, 발생하는 세척액의 pH를 6.5 이상으로 중화시켜 대부분의 유해원소를 제거할 수 있었다. 흡착제로 GFO(Granular ferric oxide)를 이용하였을 경우 비소와 납의 제거율이 뛰어났으며, 중화공정과 결합하였을 경우 대부분의 유해원소를 제거할 수 있었다. 결과적으로, 토양세척 공법 적용 시 토양의 특성에 따라 유해원소의 제거율 및 세척액의 처리 및 재이용 방법이 차이가 있으므로, 세척효율 및 세척수 처리 공정을 고려한 체계적인 최적화를 진행하여야 할 것으로 판단된다.

• ALGAE
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• 제22권4호
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• pp.319-323
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• 2007

This study was conducted with using chlorophyll a fluorescence (indicated as photosynthetic activity) to examine the toxic effect of 96 h exposure of heavy metals and herbicides on the benthic diatom Nitzschia sp. which was isolated from pristine sediment in Pamquat Harbour, Nova Scotia, Canada. Samples of benthic diatom were exposed to 0, 0.01, 0.1 and 1 mg L–1 of copper, 0, 1, 10 and 100 mg L–1 of chrome (VI), 0, 2.45, 24.5 and 245 mg L–1 of paraquat dichloride, and 0, 4.37, 43.7 and 437 mg L–1 of alachlor during 96 hours. The effective quantum yield of photochemistry (ΔF/Fm’) was evaluated by subjecting light acclimated samples to saturating pulses of light using a pulse amplitude modulated (PAM) fluorometer. The impact of heavy metals on Nitzschia sp. photosynthesis was not severe in < 1 mg L–1 but in the high concentrations (> 1 mg L–1) clearly increased toxic stress during 96 h. Herbicides had a limited impact during the exposure period but clearly increased stress on the benthic diatom with increasing concentrations. Acute response of Nitzschia sp. to selected heavy metals and herbicides was characterized, and the capacity of a benthic diatom to tolerate and recover from toxic stress was assessed.

• Environmental Analysis Health and Toxicology
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• 제2권1_2호
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• pp.43-53
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• 1987

Among the environmental toxic metals, cadmium and lead compounds are very hazard for human health because these may affect the biological function of human body and furthermore enhance the cause of various disease. In recent years, as the view of environmental toxicology, the combination of toxic metals suffering human health is especially significant cadmium chloride (10 mg/kg P. 0., 1 mg/kg I.P.) and lead acetate (20 mg/kg P.O., 2 mg/kg I.P.) were administered to rats for 4 weeks on alternate days and then examined the effect of these on body weight, tissue weight and also biochemical function in blood and tissue were investigated and comparision of the two experimental groups such as single and combined administration. According to the results of this experiment, accumulation of heavy metals increased and biological metabolic function grew worse but, in tissue, toxic effect decreased by combined administration and intraperitoneal administration was more toxic than per OS.

• Toxicological Research
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• 제31권1호
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• pp.1-9
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• 2015

Environmental toxicants such as toxic metals can alter epigenetic regulatory features such as DNA methylation, histone modification, and non-coding RNA expression. Heavy metals influence gene expression by epigenetic mechanisms and by directly binding to various metal response elements in the target gene promoters. Given the role of epigenetic alterations in regulating genes, there is potential for the integration of toxic metal-induced epigenetic alterations as informative factors in the risk assessment process. Here, we focus on recent advances in understanding epigenetic changes, gene expression, and biological effects induced by toxic metals.

• Journal of Applied Biological Chemistry
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• 제57권2호
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• pp.131-136
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• 2014

An attempt was made to assess metal ionic toxicity levels of different fishes in the polluted rivers viz., Buriganga and Turag. Fish samples collected from two polluted rivers were analyzed for the levels of metals such as Cd, Cr, Cu, Mn, Pb, and Zn in order to elucidate the status of these contaminants in fish meant for human consumption. The detected concentrations of Cr, Cu, Mn, and Zn ions in fish species collected from the polluted rivers were below the toxic levels and did not appear to pose a threat. Among the analyzed metals, Cd and Pb ions were detected above the permissible levels in liver and muscle tissues of stinging catfish (Heteropneustesfossilis), spotted snakehead (Channapunctata) and wallago (Wallagoattu) collected from the polluted rivers causing toxicity for human consumption. Stinging catfish (Heteropneustesfossilis) was the species found to highly bioaccumulate these metals. Fish species bioconcentrated appreciable amounts of Cd and Pb as toxic metals in the liver as compared to the muscle. Levels of these toxic metals varied depending on different tissues in fish species.

• 환경영향평가
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• 제9권4호
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• pp.271-276
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• 2000

The research centers on the health risk assessment of airborne toxic metals in Taejon third and fourth industrial complexes. Total suspended particulates were collected on glass microfibre filters by high volume air samplers. Fifteen toxic metals including 6 carcinogenic metals were analyzed by ICP-MS and ICP-AES after the pre-treatment of mixed acid extraction. The following results were summarized from the research : 1) the concentrations of TSPs were $17.7{\sim}219.6{\mu}g/m^3$ while the arithmetic mean concentration was $101.7{\mu}g/m^3$; 2) the arithmetic mean concentrations of human carcinogens such as arsenic, hexavalent chromium and nickel subsulfide were 10.22, 6.96 and 6.42 $ng/m^3$, respectively while those of probable human carcinogens such as beryllium, cadmium and lead were 0.13, 3.41, 97.65 $ng/m^3$, respectively; 3) the point risk estimate for the inhalation of carcinogenic metals was $1.5{\times}10^{-4}$, which was much higher than a risk standard of $10^{-5}$; 4) approximately 93% of the cancer risk were to the inhalation of human carcinogens, arsenic and hexavalent chromium, which should be properly managed in Taejon third and fourth industrial complexes.

• 대한예방한의학회지
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• 제13권1호
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• pp.93-103
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• 2009

Evidences from various countries suggest that toxic heavy metals in herbal medicine may constitute a serious health problem. In order to evaluate whether the toxic heavy metals caused by herbal medicine intake, blood samples collected from 222 patients taking herbal medicine were analyzed. In average levels of analyzed metals, $0.4{\sim}33.9%$ of total samples for 8 metals such as Cd, Co, Cu, Hg, Mn, Ni, Pb and Zn except Cr and Fe exceeded the upper limit for WHO reference value. In analysis of regression coefficients indicating the levels of metals increased or decreased after taking herbal medicine for one month, however, there were different aspects by intake types for herbal medicine. For example, the metals increased by taking decoction in blood samples were as follows; Cd and Pb whether Mn, Ni and Pb as increased metals were identified in the group taking pill and decoction(combined intake group). The odds ratio showing values higher than 1 indicating that people who take herbal medicine would have possibility higher for metal accumulation in blood than that from people who do not take herbal medicine. The metals showing the odds ratio higher than 1 were Hg and Ni in decoction group, and Cd and Hg in combined intake group. However, eight of the total, 10 metals showed the odds ratios lower than 1 by taking herbal medicine. Thus, this may explain the possible role of herbal medicine as a chelator for heavy metals in body.

• ALGAE
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• 제21권4호
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• pp.471-477
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• 2006

Amphora costata W. Smith 1853 is a down thrown diatom species and also known as metal corrosive ship-fouling organism. A. costata was isolated from Alang ship breaking yard, Alang and evaluated the toxicity tolerance and growth responses of the cultures exposed to different doses of toxic and relatively accessible heavy metals, such as Fe, Mn, Cd, Co, Cu, Zn, Ni, and Pb in the constantly monitored laboratory culture conditions. The strongest toxic effect was observed on A. costata exposed to Cd even at relatively low concentrations as compared to other metals. The following trend of decreasing order of toxicity i.e. Cd>Zn>Ni>Co>Pb>Cu>Fe was observed, when they were exposed to equal concentration and expose time.

• 환경영향평가
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• 제8권2호
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• pp.1-8
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• 1999

The research centers on the concentration profile and risk assessment of toxic metals for ambient air in Taejon industrial complex. Airborne concentrations of each toxic metal for risk assessment were obtained from 2-year sampling by high volume air sampler and analysis by ICP-MS and ICP-AES in the complex. The long-term arithmetic mean of human carcinogen, arsenic, hexavalent chromium and nickel subsulfide was 5.53, 2.16 and $3.46ng/m^3$ while the mean of probable human carcinogen, beryllium, cadmium and lead was 0.08, 2.35, $293.29ng/m^3$, respectively. And the long-term arithmetic mean concentration of non-carcinogenic metal, manganese was $55.91ng/m^3$. The point risk estimate for the inhalation of carcinogenic metals was $3.6{\times}10^{-5}$, which was higher than a risk standard of $10^{-5}$. About 75% of the cancer risk was to the inhalation of human carcinogen, arsenic. Thus, it is necessary to properly manage arsenic risk in Taejon industrial complex. The point hazard index by the inhalation of manganese was 1.1. Therefore, an investigation into Taejon industrial complex is needed to obtain more fine long-term concentration data for airborne non-carcinogenic metals including manganese.

• 한국식품과학회지
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• 제36권4호
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• pp.523-526
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• 2004

본 연구는 우리나라에서 유통되는 과일류 중 유해중금속 함량을 파악하여 각국의 모니터링 및 기준과 비교함으로써 안전성을 평가하고자 하였다. 9종(386건)의 과일류에 대하여 4개 금속(Hg, Pb, Cd, As) 함량을 수은은 Mercury Analyzer로 납, 카드뮴, 비소는 습식분해 후 ICP 및 AAS로 분석하였다. 본 연구결과로부터 알아 낸 국내에서 유통되는 과일류 중 유해중금속 평균함량은 Hg 0.001 mg/kg, Pb 0.013 mg/kg, Cd 0.006 mg/kg, As 0.017 mg/kg으로 외국에서 보고된 결과와 유사한 수준이었다. 또한 우리나라 국민이 과일류를 통해 섭취하는 수은, 납, 카드뮴 등 유해중금속량은 FAO/WHO에서 설정한 잠정주간섭취허용량(PTWI)의 약 1-2% 수준으로 낮게 나타났다.