• 한국산업보건학회지
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• 제16권1호
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• pp.27-35
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• 2006

The aim of this study was to identify the sources of benzene detected in airborne of casting workplace where benzene was not used as raw material. We have identified benzene by GC/FID and GC/MSD. In this pilot test, small size iron chamber(diameter 30 cm, height 20 cm) was used. As the raw materials, new sand, recovered sand, and mixed casting sand(new sand + solidifying agent + organic resin + coating material) was tested, respectively. In the new sand benzene was not detected, but in the recovered sand and the mixed casting sand was detected. Xylenesulfonic acid(solidifying agent), one of the mixed casting sand ingredients was thought to product benzene by thermal decomposition above $400^{\circ}$..., but the other raw materials(organic resin and coating material) were thought not to product benzene. In this experiment, the most of benzene by thermal decomposition was produced within 1 hour after pouring the iron solution($1560^{\circ}$...) in small size iron chamber. When the mixed casting sand with coating material was used, the concentration of the produced benzene was average 2.91 ppm(range 1.98~3.72 ppm), and without coating material, benzene concentration was average 0.11 ppm(range 0.08~0.14 ppm).

• 한국환경농학회지
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• 제29권4호
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• pp.421-426
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• 2010

벤젠은 농약 노출 및 새집 증후군시에 나타나는 중요한 물질로 천식 및 알러지 등의 호흡 질환을 일으키는 물질로 알려져 있으나 폐 상피세포에 대한 자세한 효과는 알려져 있지 않고 있다. 본 실험에서는 폐 상피세포인 A549 세포를 이용하여 벤젠에 대한 효과를 알아보았다. 실험 결과 벤젠은 세포 생존율을 감소 시켰으며, 이러한 반응은 항산화제인 vitamin C 및 NAC 처리 시 차단되었다. 실제로 벤젠 처리시 산화성 스트레스 지표인 lipid peroxide 형성이 증가하였으며 이들 반응 역시 항산화제들에 의해 차단되었다. 한편 벤젠 처리시 세포 사멸 촉진 단백질인 Bax 발현은 증가하였으며 세포 사멸 억제 단백질인 Bcl-2의 발현은 억제 되었으며 세포 사멸 실행 단백질인 casapse-3의 활성형 역시 증가하였다. 결론적으로 벤젠은 폐 상피세포에서 산화성 스트레스 증가를 통해 세포 사멸을 일으키는 것으로 나타났다.

• 한국미생물·생명공학회지
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• 제16권5호
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• pp.379-383
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• 1988

활성슬러지법에 의한 벤젠폐수 처리실험을 통하여 활성슬러지의 벤젠처리중에 실제 그에 관여하는 세균을 분리 동정하였다. 반응조에서 분리한 세균은 6종으로, Pseudomonas fluorescens, Enterobacter agglomerans, Enterobacter cloacae, Klebsiella oxytoca, Citrobacter freundii와 Klebsiella pneumoniae로 동정되었다. 벤젠 분해능을 측정한 결과는 P. fluorescenss가 55%를 18시간만에 처리했고, E. cloacae는 24%, K. oxytoca 는 32%, E. agglomerans는 41%의 분해능을 보였다. P. fluorescens의 증식 최적조건은 온도 25-31$^{\circ}C$와 pH 7.0으로 확인되었다. P. fluorescens가 우점종일때 나타나는 지로생물은 원생동물인 Aspidisca sp.였다. 벤젠 농도가 387mg/$\ell$일 때에는 Aspidisca sp.와 Litonotus sp.가 증식을 최대로 하였고, 벤젠 농도가 1,600mg/$\ell$에서는 Litonotus sp.와 Vorticella sp.는 거의 성장하지 않았다. Glucose 배지에서는 모두 성장율이 높았다.

• 한국환경과학회지
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• 제8권3호
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• pp.319-323
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• 1999

This study was designed to evaluate the exposure to benzene by residents in neighborhoods near a major roadways, by persons waiting buses, and by drivers and service station attendants while refueling. It was confirmed that the outdoor air benzene concentrations near the major roadways were higher than those further away from the sources. However, neither the indoor air nor breath concentrations were different for two specified residential areas. Smoking was confirmed as an important factor for the indoor air benzene levels. Persons waiting buses, drivers and service station attendants were exposed to elevated benzene levels compared to even the residents in neighborhoods near a major roadways. The mean benzene concentration at bus stop was 2.7 to 6.9 times higher than the mean ambient air concentration. The mean benzene concentrations in the breathing zone of drivers and service station attendants were 95 to 160 and 120 to 202 times higher than the mean ambient air concentrations, respectively.

• KSBB Journal
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• 제15권6호
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• pp.589-593
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• 2000

Several bacterial strains growing on benzene minimal medium were isolated from soil by enrichment culture, Burkholderia sp. SKK381 was identified and selected. In order to determine the ability of Burkholderia sp. SKK381 to degrade benzene. Changes in substrate concentration, cell growth, and pH were monitored from start-up in bath culture. At 30$^{\circ}C$, 1000 ppm of benzene was degraded 100% within 28hours. Cell growth conditions were best at an initial pH of 7.0 and a benzene concentration of 1000 ppm at 30$^{\circ}C$.

• 한국환경과학회지
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• 제7권3호
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• pp.393-400
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• 1998

A microorganism, Klebsiella gr. 47, capable of degrading BTX(benzene, toluene and xylene) was isolated from oil-contaminated soil and its characteristics of BTX degradation were investigated. When benzene and toluene were fed to Klebstella gr. 47 simulataneously, they showed competitive ingibition. The degradation rate of xylene was enhanced as much as 3 times when xylene was fed with benzene or toluene. Degradation rate of benzene and toluene was also enhanced by cocultured with Alcaligenes xylosoxidans. When benzene-adapted microorganism was used, each BTX compound was degraded efficiently within 5 hours.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2003년도 추계학술대회
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• pp.96-102
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• 2003

Benzene is an environmental pollutant that is present in mineral oil, natural gas, coal tar, gasoline, motor vehicle emissions, and tobacco smoke. The importance of benzene resides in the fact that it can induce hematotoxicity and leukemia in human and mice. However, the underlying mechanism of benzene hematotoxicity and leukemogenicity is still not fully understood.(omitted)

• Bulletin of the Korean Chemical Society
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• 제22권12호
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• pp.1287-1288
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• 2001

• 한국화재소방학회논문지
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• 제27권1호
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• pp.8-13
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• 2013

최소자연발화온도는 가연성액체의 안전한 취급을 위해서 중요한 지표가 된다. 본 연구에서는 ASTM E659 장치를 이용하여 가연성 혼합물인 Benzene과 n-Hexane 계의 최소자연발화온도와 발화지연시간을 측정하였다. 2성분계를 구성하는 순수물질인 Benzene과 n-Hexane의 최소자연발화온도는 각 각 $583^{\circ}C$, $240^{\circ}C$로 측정되었다. 그리고 측정된 Benzene과 n-Hexane 계의 최소자연발화온도는 제시된 식에 의한 예측값과 적은 평균절대오차에서 일치하였다.

• 한국대기환경학회지
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• 제19권1호
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• pp.57-66
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• 2003

TiO$_2$ sol was prepared by sol-gel method, and this sol was coated in ceramic and glass bead by dip-coating method. The coated catalyst was applied to degrade benzene in the gas phase by exposing to UV -lamp (365 nm) in a batch reactor. The removal efficiency of the benzene was compared by changing various conditions such as the kind of chemical additives, the coating beads (ceramic and glass), solution pH, the initial concentration of TiO$_2$ sol, UV intensity, and benzene concentration. The physical structure of TiO$_2$ sol used in this study was found to be pu-rely anatase type from XRD analysis. The results showed that ceramic bead was effective as the coating agent rath-er than glass bead. The significant change in the benzene removal efficiency of benzene did not occur with chang-ing coating frequency and the initial concentration of TiO$_2$ sol. The removal efficiency of benzene increased with increasing UV intensity, and with acidic treatment of TiO$_2$-coated ceramic bead.