The Cytogenetic Effects of Benzene and Toluene on Bone Marrow Cells in Rats

Roh, Jaehoon,Moon, Young Hahn,Kim, Kir-Young Yonsei University, College of Medicine 1987 Yonsei medical journal Vol.28 No.4

스코리아를 담체로 한 Biofilter에서 Benzene 제거 특성

이석희,이동환,이민규 한국화학공학회 2003 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.41 No.6

제주도 스코리아를 충전한 바이오필터에서 기상 benzene의 생물분해능을 조사하였다. Benzene 분해 미생물 균주는 Bacillus sp.를 사용하였다. 회분식 실험 결과로부터 benzene에 대한 Bacillus sp의 비증식 속도는 0.037 hr^(-1)로 얻어졌다. 연속식 바이오필터 운전에서 benzene의 유입농도가 600 ppmv일 때 공탑접촉시간(EBCT)가 20 sec 이상에서는 거의 100% 제거되었으며, EBCT를 10 sec로 낮추더라도 제거효율은 90% 이상 유지되었다. Benzene에 대한 최대 제거용량은 720 g/㎥·hr이었다. 약 200일 동안 연속 운전하였으나 전체적으로 드레인수의 pH는 6-7로 거의 일정하게 유지되었으며, 압력 강하는 평균 5 mm H₂O로 낮은 압력 강하를 보였다. 층 깊이에 따른 benzene의 농도 변화는 1차 반응 모델식을 만족하였다. The biodegradation of benzene vapor in the biofilter packed with scoria, which was from Jeju island, was investigated. Bacillus sp. was used as a benzene oxidizer. Batch experiment results showed that the specific growth rate of Bacillus species was 0.037 hr^(-1) for benzene. In the continuous biofilter operation, the empty bed contact time (EBCT) was changed from 5 to 60 sec with a fixed concentration of benzene at 600 ppmv. At the EBCTs up to 20 sec, the removal efficiency was over 99.9%. When the EBCT was further reduced to 10 and 5 sec, the removal efficiency decreased to 90% and 45%. respectively. The maximum capacity of benzene was 720 g/㎥·hr. During the 200 days operation, the biofilter gave a stable removal efficiency such that the pH of a drain water was maintained at 6-7 and the pressure drop was about 5 ㎜H₂O. The results for the benzene vapor concentration with respect to filter height followed the first order kinetics.

Stenotrophomonas maltophilia T3-c에 의한 벤젠 분해 특성

조경숙,전연신,이은영,류희욱 한국냄새환경학회 2002 실내환경 및 냄새 학회지 Vol.1 No.1

VOC 제거용 biofilter로부터 benzene 분해 세균인 Stenotrophomonas maltophilia T3-c 균주를 신규로 분리하여, 분리 균주의 benzene 분해속도에 미치는 기질농도, 배지의 pH, 배양 온도의 영향을 살펴보았다. 약 28~85 μmol의 범위에서 benzene의 첨가량이 증가할수록 benzene 분해속도도 증가하였고, benzene의 초기 농도가 85 μmol인 경우 benzene 비분해속도는 12 mmol-benzene․g-DCW-1․h-1이었다. pH와 온도의 영향을 살펴본 결과, S. maltophilia T3-c 균주는 pH가 5에서 8까지의 일반적인 중성 영역에서는 거의 비슷한 속도로 benzene을 분해할 수 있었으나, 벤젠의 생분해 속도는 온도에 크게 영향을 받았다. S. maltophilia T3-c 균주는 pH 7과 30℃ 조건에서 벤젠을 가장 잘 분해할 수 있었다. A benzene degrading bacterium, Stenotrophomonas maltophilia T3-c was isolated from the biofilter for the control of BTEX. Environmental factors such as initial substrate mass, pH in the medium, and incubation temperatures effect on the degradation rate of benzene were investigated. Within the range of initial benzene mass from 28 to 85 μmol, an increased substrate concentration increased the specific degradation rate of benzene. The specific degradation rate of benzene was 12 mmol-benzene․g-DCW-1․h-1 at the initial benzene mass of 85 μmol. The benzene degradation rate of S. maltophilia T3-c was maintained over a broad range of pH 5~8. Benzene degradation rate was highly dependent on the operation temperature. The optimum temperature and pH for the degradation of benzene by S. maltophilia T3-c was 30℃ and pH 7, respectively.

B-시클로덱스트린(B-Cyelodextrin)의 결합 특성과 벤젠의 생물학적 분해에의 적용에 대한 연구

최종규,손현석,조경덕 한국환경보건학회 2002 한국환경보건학회지 Vol.28 No.5

Recently, surfactants were frequently used in order to desorb the hydrophobic organic compounds (HOCs) from soil and to enhance the bioavailability. Among them, j3-cyclodextrin (B-CD) is one of those. This study was performed to investigate the binding characteristics between benzene and B-CD and to examine the bioavailability of benzene. First, we investigated binding charasteristics between benzene and B-CD in waterand water/soil system. Then, we examined the effect of B-CD on the biodegradation of benzene in water and water/soil system. Experimental results on the binding characteristics showed that I3-CD resulted in an efficient complex formation with benzene. As B-CD concentration increased, the benzene concentration complexed with B-CD rapidly increased to 30-40% initial benzene added, and reached the equilibrium. We also investigated the effect of B-CD on the desorption of benzene from soil in the water/ soil system. As I3-CD concentration increased, benzene concentration desorbed into water increased up to 90%. However, in its application to biodegradation of benzene in water and water/soil system, the biodegradation rate of benzene did not improved in the presence of B-CD compared with in the absense of B-CD. This result indicated that V was more preferentially used as a carbon source than benzene. Therefore, for remediation of benzene contaminated soils, B-CD can be used as a surfactant to desorb benzene from soil, and then ex-situ chemical treatment can be applied for the remediation.

$\beta$-시클로덱스트린($\beta$-Cyclodextrin)의 결합 특성과 벤젠의 생물학적 분해에의 적용에 대한 연구

최종규,손현석,조경덕 한국환경보건학회 2002 한국환경보건학회지 Vol.28 No.5

Recently, surfactants were frequently used in order to desorb the hydrophobic organic compounds (HOCs) from soil and to enhance the bioavailability. Among them, -cyclodextrin ($\beta$-CD) is one of those. This study was performed to investigate the binding characteristics between benzene and $\beta$-CD and to examine the bioavailability of benzene. First, we investigated binding characteristics between benzene and $\beta$-CD in water and water/soil system. Then, we examined the effect of $\beta$-CD on the biodegradation of benzene in water and water/soil system. Experimental results on the binding characteristics showed that $\beta$-CD resulted in an efficient complex formation with benzene. As -CD concentration increased, the benzene concentration complexed with $\beta$-CD rapidly increased to 30-40% initial benzene added, and reached the equilibrium. We also investigated the effect of $\beta$-CD on the desorption of benzene from soil in the water/soil system. As $\beta$-CD concentration increased, benzene concentration desorbed into water increased up to 90%. How-ever, in its application to biodegradation of benzene in water and water/soil system, the biodegradation rate of benzene did not improved in the presence of $\beta$-CD compared with in the absense of $\beta$-CD. This result indicated that $\beta$-CD was more preferentially used as a carbon source than benzene. Therefore, for remediation of benzene contaminated soils, $\beta$-CD can be used as a surfactant to desert benzene from soil, and then ex-situ chemical treatment can be applied for the remediation.

Evaluation of headspace-gas chromatography/mass spectrometry for the analysis of benzene in vitamin C drinks; pitfalls of headspace in benzene detection

Ju, Hyun Kyoung,Park, Jeong Hill,Kwon, Sung Won John Wiley Sons, Ltd. 2008 Biomedical chromatography Vol.22 No.8

<P>Recently, there have been reports regarding the presence of benzene in vitamin C drinks. This is caused by sodium benzoate and ascorbic acid (vitamin C), which can react together to induce benzene formation. While the headspace gas chromatography method is well known for the detection of benzene, there could be pitfalls in the process of benzene extraction. This study was performed to check if benzene could be generated under high-temperature incubation conditions. As a result, the amount of benzene detected by headspace-gas chromatography/mass spectrometry (HSGC/MS) was affected by temperature changes. As the temperature of the sample vial was increased, newly generated benzene from the headspace also increased, causing false-positive determination of benzene. Although 80°C is generally accepted for the temperature of headspace sample vials, lower temperatures, such as 40°C, minimize the false-positive identification of benzene. Considering that this minimization allows benzene to be quantified at around 5 ppb, this lower temperature should definitely be considered since benzene, which is formed in sodium benzoate, can appear in vitamin C drinks under certain circumstances. The proposed analysis method of benzene in vitamin C drinks by HSGC/MS at 40°C is an accurate and universal method for the monitoring of benzene without false-positive identification. Copyright © 2008 John Wiley & Sons, Ltd.</P>

망간 기반 촉매상에서의 벤젠의 산화와 오존산화에 대한 최근 연구 동향

박성훈 ( Sung Hoon Park ),전종기 ( Jong Ki Jeon ),김상채 ( Sang Chai Kim ),정상철 ( Sang Chul Jung ),박영권 ( Young Kwon Park ) 한국공업화학회 2014 공업화학 Vol.25 No.3

벤젠은 발암성을 가진 유해성 대기 오염물질로 특별한 관리가 필요하다. 특히 벤젠은 실외 뿐만 아니라 실내에서도존재하기 때문에 실내외를 구분하여 적절한 처리 방법이 요구된다. 실외의 공정에서 배출되는 VOC는 촉매 산화법을통하여 300-400 ℃에서 제거하는 것이 바람직하지만, 실내의 경우는 100 ℃ 이하 혹은 실온에서 제거되는 것이 바람직하다. 본 총설은 촉매산화법, 촉매오존산화법 등 다양한 촉매 벤젠 산화법의 최근 동향을 다루고 있으며, 특히 저온산화반응을 위해 Mn 기반 촉매에 중점을 두고 조사하였다. Mn 기반 촉매는 다른 귀금속 촉매에 비하여 경제적으로매우 이로우며, 특히 다양한 제조법을 적용하여 보다 효율적인 Mn 기반 벤젠 제거 촉매가 개발되고 있다. 또한 오존을이용하여 100 ℃ 이하, 특히 상온에서도 효율적으로 벤젠을 제거할 수 있기 때문에, Mn 기반 촉매의 효율성은 더욱더 증가할 것으로 판단된다. Benzene is a hazardous air pollutant, classified as carcinogenic to humans, that requires special management. Benzene existsboth indoors and outdoors and the control measure of indoor benzene is different from that of outdoor benzene. The removalof indoor benzene needs to be accomplished at low temperatures (normally below 100 ℃), while outdoor benzene is usuallyremoved at much higher temperature (300-400 ℃) by using catalytic oxidation. This review paper summarizes the recent trendin catalytic treatment of airborne benzene, focusing on catalytic oxidation and catalytic ozone oxidation. Particular attentionis paid to Mn-based catalysts for low-temperature oxidation of benzene, which are more economical than the other noble-metalcatalysts. Various methods are used to generate more efficient Mn-based catalysts for benzene removal. Ozone oxidation isattracting particularly significant attention because it can remove benzene effectively below 100 ℃, even at room temperature.

벤젠 대사에 있어서 GST Subfamily와 NQO1 유전자다형성의 영향

정효석(Hyo Seok Jeong),김기웅(Ki-Woong Kim),이종은(Jong Eun Lee),이원택(Won Taek Lee),박경아(Kyung Ah Park),장성근(Sung Keun Chang) 대한해부학회 2003 Anatomy & Cell Biology Vol.36 No.4

본 연구는 정유회사 근로자 90명를 대상으로 하여 benzene의 노출농도와 대사산물인 phenol의 배설량을 측정한 후, benzene의 대사에 관여하는 glutathione S-transferase (GST)M1, GSTT1, GSTP1과 NAD(P)H: quinone oxidoreductase (NQO1) 유전자다형성을 분석하여 이들 효소의 유전자 아형 (genotype)에 따라 benzene의 대사에 어떠한 영향을 미치는지를 파악하고자 하였다. 연구 대상자들이 노출되는 benzene의 평균농도는 0.042±0.069 (mean±S.D) mg/m3이었고, 뇨중으로 배설되는 phenol의 평균 배설량은 7.42±11.3 (mean±S.D) mg/g creatinine으로, 상관성 (r)은 0.604 (p⁄0.01)이었다. benzene의 대사와 이들 효소의 유전자다형성에 대한 상관성을 보면, benzene의 대사산물인 phenol의 배설량과 GSTM1과 GSTT1 null 아형에서는 0.769과 0.863의 상관성을 보였고 (p⁄0.01), present 아형보다 다소 높은 상관성을 보였다. 또한 GSTP1의 경우에도 GSTP1*1/*1 유전자 아형이 GSTP1*1/*2 (r = 0.413, p⁄0.05)보다 높은 상관성을 보였다. 그리고 NQO1에서의 polymorphic site가 존재하는 아형(r = 0.833, p⁄0.01)과 존재하는 않는 유전자 아형 (r = 0.877, p⁄0.01)에서 비슷한 상관성을 보였다. 이러한 현상은 Cytochrome P450 2E1 CYP2E1에 의하여 benzene의 대사가 촉진되어 phenol의 생성이 증가되고, 포합반응 은 활성이 결여된 GST subfamily null 유전자 아형보다 present 아형에 의해서 이루어지는 것으로 보인다. 또한 NQO1의 경우에 polymorphic site가 있는 유전자와 없는 유전자 아형에서 비슷한 상관성을 보인 것은 phenol이 semiquinone계 물질로 대사 변형되는 기전보다 다른 기전을 통하여 대사 변형되는 경로가 우세하기 때문에 상대적으로 생성되는 물질의 양이 적어서 유전자 아형에 따른 차이를 보이지 않은 결과로 생각된다. The higher concentration of traces of aromatic hydrocarbons prevailing in the refinery atmosphere causes severe occupational health hazard to refinery workers. In this study, the biochemical role of genetic polymorphism in modulating urinary excretion of benzene metabolite as phenol level has been investigated in 90 workers exposed to benzene in the petroleum refinery plants of Korea. Glutathione S-transferase (GST) subfamily as GSTM1, GSTT1 and GSTP1 and NAD(P)H: quinone oxidoreductase 1 (NQO1) gene polymorphisms were determined by polymerase chain reaction (PCR)-based methods. The mean concentration of volatile benzene in the refinery environment was 0.042 mg/m3 (SD, 0.069) and that of urinary phenol was 7.42 mg/g creatinine (SD, 11.3). The airborne benzene concentration was significantly related to the concentration of phenol in urine (r = 0.640, p⁄0.01). However, all the genotypes of GST subfamily and NQO1 except small sample size of genotypes in GSTM1 and GSTT1 none of them were higher than that of present genotype. Also, it was higher in the GSTP1*1/*1 than in the GSTP1*1/*2. The various biological (i.e. age and liver function parameters) or lifestyle factors (i.e. medication, smoking, alcohol and coffee intake), also taken into account as potential confounders, did not influence the correlations found. These results suggested that GST subfamily and NQO1 genotypes might play an important role in the metabolism of benzene.

Benzene increases the ratio of arachidonic acids to docosahexaenoic acids and inhibits the de novo synthesis of ceramide in the rat liver

Sul, Donggeun,Shim, Ilsub,Im, Hosub,Won, NamHee,Kim, Hae-Joon,Lee, Eunil WILEY 2005 Journal of Applied Toxicology Vol. No.

<P>The present study investigated the effects of inhalation exposure of benzene at 0, 10, 200 and 600 ppm for 1, 2 and 4 weeks on n-6 and n-3 fatty acids and ceramide levels in the rat liver. No signicant difference in the ratio of saturated fatty acid to unsaturated fatty acid was found on increasing benzene exposure levels, but the ratio of saturated fatty acid to unsaturated fatty acid decreased with increasing benzene exposure times, with the exception of the phospholipids of rats exposed to 200 and 600 ppm of benzene. A signicant increase in the ratio of arachidonic acid to docosahexaenoic acid was found in the phospholipids of rats exposed to 200 and 600 ppm of benzene for 4 weeks. In our study, no change in the relative amounts of sphingomyelin in phospholipids, due to benzene exposure at 600 ppm for 4 weeks resulted in the lack of sphingomyelin turnover. However, ceramide levels in the livers of rats exposed to 600 ppm of benzene for 4 weeks were signicantly reduced upon increasing the benzene concentration. This result shows that the de novo synthesis of ceramide was signicantly inhibited at higher levels of benzene and that the ratio of arachidonic acid to docosahexaenoic acid in phospholipids is dose-dependently related to benzene exposure. Copyright © 2005 John Wiley & Sons, Ltd.</P>

반연속배양의 혼합균주에 의한 Benzene, Toluene 및 Phenol 혼합물 분해

오희목,김서인,이창호,서현효,이문호,고영희,윤병대 한국산업미생물학회 1994 한국미생물·생명공학회지 Vol.22 No.4

Benzene, toluene 및 phenol을 각기 250 ㎎/ℓ 포함한 합성폐수에 혼합균주인 GE1을 접종하고 반연속배양에 의하여 군집의 안정을 이룬 후 방향족화합물의 생분해에 대하여 조사하였다. 미생물 무처리구인 대조구에서 75 ㎖/ℓ/min의 폭기에 의해 배양 24시간에 phenol은 37%, benzene은 83%가 휘발되고, toluene은 배양 12시간에 모두 휘발되었다. Benzene과 toluene의 생분해는 섬모상 고정화 담체를 설치한 SB(strains+biofilm) 처리구에서 효과적이며, phenol은 glucose를 첨가한 SG(strains+glucose) 처리구에서 보다 신속히 분해되었다. Benzene, toluene 및 phenol을 250 ㎎/ℓ 또는 1000 ㎎/ℓ 첨가하였을 때 SG 처리구는 16시간이나 32시간에 이들 화합물을 완전히 제거하였다. COD 제거율은 SG 처리구에서 초기에 80 ㎎/ℓ/h로 가장 높았으나, 증식된 균체량에 의하여 배양 12시간 이후에는 116∼140 ㎎/ℓ의 일정한 값을 보였다. 결론적으로 혼합균주 GE1은 benzene, toluene 그리고 phenol 등의 방향족화합물이 혼합된 산업폐수의 처리에 폭 넓게 사용될 수 있는 가능성을 보였다. The biodegradation of aromatic compounds by a mixed culture GE1 was investigated in an artificial wastewater containing 250 ㎎/ℓ of benzene, toluene, and phenol in semicontinuous culture. In the control group (no strains) with an aeration rate of 75 ㎖/ℓ/min, 37% of phenol and 83% of benzene were volatilized during early 24 hrs and toluene was disappeared form the medium within 12 hrs. The biodegradation of benzene and toluene was effective in SB (strains+biofilm) treatment, while phenol was degrade more quickly in SG (strains+glucose) treatment including glucose as an additional carbon source. Aromatic compounds added at a concentration of 250 ㎎/ℓ or 1000 ㎎/ℓ were completely removed by SG treatment after 16 hrs or 32 hrs, respectively. The removal rate of COD was high as much as 80 ㎎/ℓ/h in SG treatment during early period, but COD revealed a stable value of 116∼140 ㎎/ℓ after 12 hrs caused by increased biomass. Therefore, it is concluded that the mixed culture GE1 could be used for the wastewater treatment including aromatic compounds such as benzene, toluene, and phenol.