• Title/Summary/Keyword: 생물축적농도

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노출평가를 위한 TLV 근거 - 2-BUTOXYETHANOL(8)

  • Kim, Chi-Nyeon
    • 월간산업보건
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    • s.379
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    • pp.9-16
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    • 2019
  • 2-부톡시에탄올(2-butoxyethanol)에 대한 생물학적 노출지수 설정에 필요한 자료는 상당수 존재한다. 다양한 실험실 및 직업적 현장연구는 2-butoxyethanol에 노출된 후 소변에서 butoxyacetic acid의 배설을 조사하여 생물학적 노출지수를 구축할 데이터베이스를 제공하였다. 실험실 연구는 작업시간 동안보다는 짧은 시간을 노출시킨다. 휴식 중에 실시한 실험 자료들을 20ppm에 8시간 노출로 외삽하면 작업시작 종료 시점의 소변 중 butoxyacetic acid의 농도가 각각 192, 272, 190 mg/g creatinine이었다. 작업부하 30 watts와 50 watts의 연구 결과를 외삽하면 각각 304 butoxyacetic acid/g creatinine과 313 butoxyacetic acid/g creatinine이었다. 작업현장 연구는 소변을 가수분해시킨 후 총 butoxyacetic acid의 검출 범위가 광범위할 것으로 예상된다. 이러한 외삽의 결과는 일반적으로 1ppm 미만의 노출에서 나온 것이라는 점에 유의해야 한다. 피부 흡수의 가능성과 2-butoxyethanol의 상대적으로 낮은 휘발성을 감안할 때 현장 연구에서는 피부 경로가 흡입 연구보다 더 중요할 수 있다. 따라서 현장 조사는 휴식을 취한 자원봉사자를 대상으로 실시한 흡입 연구와 비교하면 소변 중 butoxyacetic acid 농도를 과대평가하는 경향이 있다. 활용 가능한 시뮬레이션 연구에서 휴식 시 2-butoxyethanol의 TLV-TWA 20ppm에 8시간 전신(흡입과 피부) 노출되는 경우 가수분해된 총 butoxyacetic acid가 210 mg/g creatinine이 예상되고 작업부하 50 watts에서는 373 mg/g creatinine이 예측된다. 50 watts의 작업량으로 20ppm에서 8시간 노출되는 경우 생물학적 노출지수(BEI)는 약 400 mg/g creatinine일 것이다. 그러나 생물학적 노출지수는 외삽에 대한 불확실성, 심각한 피부 노출 및 작업장 노출평가 자료의 부족을 반영하여 200 mg butoxyacetic acid/g creatinine으로 설정하였다. 인용한 자료들의 한계에도 불구하고 자원 봉사자 연구와 시뮬레이션 연구의 자료들이 일치성이 있었다. 연구에 따르면 butoxyacetic acid는 측정 가능한 양으로 존재하며 작업 교대 중에 검출될 수 있는 충분한 시간의 반감기를 가지고 있다. Sakai 등의 연구 자료와 일부 모델링 자료에서 노출농도가 높은 경우 주중에 약간의 축적 가능성을 보고하였지만 작업장에서 일반적으로 노출되는 농도 범위에서는 누적이 예상되지 않으며 작업 종료 후에 소변시료를 채취하는 것이 바람직하다. 대다수의 연구에서 소변 중 butoxyacetic acid 농도 수준의 개인 간 다양성을 보고하였다. 또한 대부분의 작업현장 연구에서는 2-butoxyethanol의 주변 환경 농도수준과 소변 중 butoxyacetic acid 수준에 유의한 상관관계를 발견하지 못하였다. 상호 연관성이 결여된 원인은 대부분 피부 노출의 영향으로 추정하였다. 개인 보호 장갑을 착용한 근로자들에게서는 유의한 상관관계가 발견되었다.

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Nitrite Accumulation Characteristics According to Hydraulic Retention Time and Aeration Rate in a Biological Aerated Filter (생물여과 반응기에서 수리학적 체류시간 및 폭기량에 따른 아질산 축적 특성)

  • Yoon, Jong Moon;Kim, Dong Jin;Yoo, Ik-Keun
    • Korean Chemical Engineering Research
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    • v.44 no.2
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    • pp.200-206
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    • 2006
  • In a biological aerated filter (BAF) packed with ceramic media (void fraction of BAF=0.32), nitrite accumulation was studied with the variation of hydraulic retention time (HRT) and superficial air velocity. Synthetic ammonium wastewater and petrochemical wastewater were fed at a constant load of $1.6kgNH_4^+-N/m^3{\cdot}d$. Ammonium removal rate was mainly affected by the superficial air velocity in BAF, but nitrite ratio($NO_2-N/NO_x-N$) in the effluent was dependent on both HRT and superficial air velocity. For a fixed HRT of 0.23 hr (corresponding to the empty bed contact time of 0.7 hr) ammonium removal rate was 73/90/92% and nitrite ratio was 0.92/0.82/0.48 at the superficial air velocity of 0.23/0.45/0.56 cm/s, respectively. When HRT is increased to 0.9 hr with superficial air velocity ranging from 0.34 to 0.45 cm/s, the ammonium removal rate was 89% on average. However nitrite ratio decreased significantly down to 0.13. When HRT was further increased to 1.4 hr, ammonium removal rate decreased, thereby resulting in the free ammonia ($NH_3-N$, FA) build-up and nitrite ratio gradually increased (>0.95). Although aeration rate and FA concentration at HRT of 0.23 hr were unfavorable for nitrite accumulation compared with those at HRT of 0.9 hr, nitrite ratio at HRT of 0.23 hr was higher. Taken together, HRT and nitrogen load were found to be critical, in addition to FA concentration and aeration condition, for nitrite accumulation in the BAF tested in the present study.

The Cd and Pb Accumulation in Various Tissues of Rooted Cuttings of Four Populus Species Inoculated with Ectomycorrhizal Fungi, Pisolithus tinctorius (모래밭버섯 균근균(菌根菌)으로 접종(接種)한 포플러 4개(個)개 수종(樹種) 삽목묘(揷木苗)의 체내(體內) 부위별(部位別) Cd과 Pb 축적(蓄積) 특성(特性))

  • Han, Sim Hee;Lee, Kyung Joon;Hyun, Jung Oh
    • Journal of Korean Society of Forest Science
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    • v.90 no.4
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    • pp.495-504
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    • 2001
  • The objectives of this study were to understand the characteristics of Cd and Pb accumulation in various tissues of poplar species and the effects of ectomycorrhizal inoculation on the accumulation of above two heavy metals in the tissues. The mycelial inoculum of ectomycorrizal fungus, Pisolithus tinctorius was produced in peatmoss and vermiculite mixtures, and inoculated into potted soil with fresh cuttings of four species of Populus, P. alba ${\times}$ glandulosa (Pag). P. koreana ${\times}$ nigra var. italica (Pkn), P. nigra ${\times}$ maximowiczii(Pnm), and P. euramericana(Pe). The potted soils were added with 0, 30, and 80 ppm Cd, and 0, 50, and 300 ppm Pb. The cuttings were grown outdoors for about five months until the plants were harvested for measurement of growth, mycorrhizal infection, and metal contents in leaves, stems, and roots. The total dry weight of Pe treated with Cd and Pb was increased by mycorrhizal inoculation, while that of three other species was not affected by the inoculation. Cd was accumulated in the highest concentration in Pag and its concentration was increased by four times by mycorrhizal inoculation. The Pag accumulated Cd in the highest concentration in the leaves, while three other species accumulated Cd most in the roots. Pb was accumulated in the highest concentration in the roots of all the four species, while Pkn accumulated Pb in the leaves as much as in the roots. Without mycorrhizal inoculation Pe accumulated Pb most among the four species, while Pkn with mycorrhizal inoculation accumulated Pb two times more than in the same species without mycorrhizal inoculation. It was concluded that Pag was the most effective species among the four poplar species in Cd absorption from contaminated soil, and that Pe instead effectively absorbed Pb. Mycorrhizal inoculation increased the Cd accumulation in the tissues by four times in Pag and also increased Pb accumulation by two times in Pkn, with leaves being the major sites of metal accumulation. It may be possible to use these two poplar species in remedying the metal in the soil through the raking and removing the litter out of the contaminate site.

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A Role of Indole-3-acetic Acid on the Growth and the Accumulation of Tannin in Callus Induced from Gallas of the Sumac (붉나무충영의 배양조직에서 생육 및 tannin 축적에 미치는 indole-3-acetic acid의 역할)

  • Xu, Ming-Zi;Oh, In-Suk;So, Sang-Sup
    • Korean Journal of Environmental Biology
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    • v.19 no.4
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    • pp.248-253
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    • 2001
  • These studies were carried out to examine the developmental process of galls caused by aphids in Rhus gavanica and the effects of indole-3-acetic acid (IAA) and ${\alpha}$-naphthalene acetic acid (NAA) on the tannin accumulation in the callus induced from that galls. The results are follows. The development of fist-shaped galls has begun at the beginning of June earlier than the case of finger-shaped galls, and also, the growth of fist-shaped galls has last to September longer than the period of finger-shaped galls. These results indicate that the life cycle and feeding activity of the aphids inhabited in fist-shaped galls were longer and mire active than the case of the aphids inhabited in finger-shaped galls. Tannin contents of fist-shaped galls revealed about 60${\sim}70%$ of total dry weights during the whole growth periods, however, the contents in finger-shaped galls were under 10% at the maximum value. These facts mean that finger-shaped galls seem to be as a habitat of aphids rather than as a major source of tannin such as fist-shaped galls. The growth of callus induced from fist-shaped galls was the most effective in the plot of $10^{-5}$ mole IAA, but the tannin accumulation in callus growth was not even caused in any plots of IAA treatments as wells as in any NAA plots. These results considered that the tannin accumulation in fist-shaped galls may be caused only in specific relation between host plant and life cycle of aphids.

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A Geo-statistical Assessment of Heavy Metal Pollution in the Soil Around a Ship Building Yard in Busan, Korea (통계지표를 활용한 부산지역 조선소 주변 토양 내 중금속 오염조사 연구)

  • Choi, Jung-Sik;Jeon, Soo kyung
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.24 no.7
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    • pp.907-915
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    • 2018
  • With the increase of metal usage in various industries, metal pollution and ecological toxicity in the environmental system have become a significant concern. A geo-statistical index has been widely used to determine contamination level with normalization through a background value. In this study, geo-statistical indexes such as an enrichment factor, accumulation index, and potential ecological risk index were used to assess metal pollution in soil at locations associated with shipbuilding manufacturing industries. Metal contamination, especially of Cu and Pb, was observed in some samples located closer to manufacturing sites. Enrichment factor and accumulation (IGEO) values were indicative of concerning levels of soil contamination in specific samples, and the soil contamination could be induced by anthropogenic sources. In further study, after more detailed sampling for soil and potential pollution sources, high interpretation techniques such as Pb isotope analysis and X-ray analysis will be needed to investigate source identification.

Removal of Mixed Cd, Cr, Cu, Ni and Zn by Hibiscus canabinas (Hibiscus canabinas를 이용한 Cd, Cr, Cu, Ni 및 Zn의 제거)

  • 최문술;임철호
    • Korean Journal of Environmental Biology
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    • v.22 no.1
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    • pp.120-126
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    • 2004
  • Kenaf plants were hydroponically grown in reactor containing toxic metals as Cd, Cu, Cr, Ni and Zn to examine the ability to take up heavy metal. The plants were fertilized using a nutrient solution, which was appropriately adjusted to optimum pH, DO and conductivity. For n hydraulic retention time of 8 days, Cr, Cd, Cu, Ni and Zn were removed up to 90.5, 80.5, 66.1%, 71.1% and 79.4%, and reduced from 2.34 to 0.54 mg $L^{-1}$, 3.37 to 1.07 mg $L^{-1}$, 4.92 to 3.19 mg $L^{-1}$, 6.31 to 4.41 mg $L^{-1}$ and 6.27 to 2.09 mg $L^{-1}$. Especially, accumulation rate of Cr, Cd, Cu, Ni and Zn in the plant were measured up to 347.32, 275.39, 157.52, 50.48 and 211.01 mg DW kg $L^{-1}d^{-1}$, respectively. We considered that Kenaf plants removed Cr, Cd and Zn more effectively than other toxic metals applied.

Heavy Metal Accumulation Analyses of the Korean Water Deer (Hydropotes inermis argyropus) in Cheorwon, Gangwon Province and the Eastern Part of Jeonnam Province (강원도 철원지역과 전라남도 동부지역에 서식하는 한국고라니(Hydropotes inermis argyropus)의 중금속 축적 분석)

  • Park, Bo-Hyeon;Kim, Baek-Jun;Lee, Sang-Don
    • Korean Journal of Environmental Biology
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    • v.27 no.4
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    • pp.363-368
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    • 2009
  • The Korean water deer (Hydropotes inermis argyropus) is an endemic species and one of the common species in Korea. The species ranges throughout the Korean peninsula and plays an important role as herbivores in natural ecosystem. Therefore, the species could be used as a good bio-indicator to monitor the quality of habitats. This study was to estimate the concentrations of five heavy metals (Fe, Cu, Zn, Cd and Pb) from three different organs (kidney, liver and spleen) in the Korean water deer. According to the analyses of heavy metal accumulations, the concentration of Fe is higher than Cu, Zn, Cd and Pb from all the organs. Among the organs, spleen (286.50) showed higher heavy metal concentrations than kidney (39.40) and liver ($23.21\;{\mu}g\;g^{-1}$). In general, the concentrations of the heavy metals were about two times higher in Cheorwon, Gangwon province than in the Eastern part of Jeonnam province. In particular, Cd and Pb showed a significant difference (P<0.05). Except for Fe in spleen, all of the heavy metal concentrations were below background levels.

${\cdot}$ 무기 복합 고분자를 이용한 granule의 활성도 실험

  • Jeong, Hyeon-Seong;Kim, Yong-Hwan;Ryu, Jeong-Yong;Song, Bong-Geun;Lee, Sang-Il
    • 한국생물공학회:학술대회논문집
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    • 2003.04a
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    • pp.676-679
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    • 2003
  • Long time over 6 month was required to form granuler sludge, which is critically necessary for UASB reactor. By feeding both high molecular cationic polymer and anionic silica sol to conventional digestion sludge, granular sludge was obtained within 5 minutes. Succession adaptation was performed for granular sludge for 30 days. $80{\sim}90%$ COD removal efficiency was shown with granular sludge, which was comparable with that of typical UASB granular sludge.

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Mathematical Analysis of a High Density Animal Cell Culture with a Spin-Filter (회전식 여과기를 이용한 고농도 동물세포배양의 수학적 해석)

  • 박흥우
    • KSBB Journal
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    • v.9 no.2
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    • pp.230-237
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    • 1994
  • Spin-filters are used as cell separation devices for achieving high cell density and high productivity in animal cell culture. We have proposed a model for the cell growth in a spin-filter perfusion culture and examined the effects on cell growth by several parameters including ammonia inhibition, specific growth rate, specific feeding rate, and cell retention. Results from computer simulation and sensitivity analysis indicate that the cell retention affects the cell growth mostly while there is a significant inhibition on cell growth by the ammonia accumulated during the culture. The specific feeding rate has minimal effects on cell growth, which is consistant with the fact that the cell growth with a step feeding is quite similar to that with a continuous feeding.

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Community structure analysis of nitrifying biofilms by 16S rRNA targeted probe and fluorescence in situ hybridization (FISH)

  • Han, Dong-U;Kim, Dong-Jin
    • 한국생물공학회:학술대회논문집
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    • 2001.11a
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    • pp.282-285
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    • 2001
  • The microbial community structure and in situ spatial distribution of ammonia oxidizing and nitrite oxidizing bacteria in nitrifying biofilm of an upflow biological aerated filter system were investigated. The reactor had been continuously operated under high free ammonia concentration and low DO concentration for nitrite accumulation more than 2 years before the experiment. Fluorescence in situ hybridization

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