• Journal of Preventive Medicine and Public Health
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• 제28권2호
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• pp.386-397
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• 1995

A cross sectional study was performed to evaluate the neurobehavioral effects of chronic exposure of complex organic solvents, using NCTB(Neurobehavioral Core Test Battery) recommended by WHO(World Health Organization). Forty female shoe factory workers and twenty-two controls matched with age were participated. The tests were performed in the morning before start of work, to exclude the effects of acute exposure. Workers were exposed mainly to toluene, methyl ethyl ketone, n-hexane, cyclo-hexane, dichloroethylene, trichloroethylene, benzene, xylenes etc. The ranges of present solvent exposure of hygienic effect were $0.46\sim0.71$ in the process using adhesives indirectly, and $1.83\sim2.39$ in the process using it directly. We reclassified the subjects, according to cumulative exposure. It showed significantly poorer performances in high exposed group on Santa Ana Dexterity and Benton Visual Retention, compared with control group. After controlling confounder, the significances were still remained. But, further cohort studies, having the information of personal exposure dose from entering a factory, are required to clarify the effects of chronic exposure of complex organic solvents in relation to dose and duration of exposure.

• 한국대기환경학회지
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• 제26권4호
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• pp.357-366
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• 2010

The purpose of this study is to evaluate a method for the measurement of N,N-Dimethylformamide (DMF) and to apply the method to the ambient air samples. For the determination of DMF together with other general VOCs (e.g., benzene, toluene, and xylenes), adsorption sampling and thermal desorption with GC/MS was used in this study. The sampling and analytical approaches tested in this study showed a good repeatability and linearity with lower detection limits of less than 0.35 ppb. Field measurements were carried out at three industrial sites (Daegu-Seongseo, Siwha and Banwall industrial complexes) and one residential site in Daegu city during a period from October 2006 to November 2008. DMF was detected in 71.8% of the total samples from the Seongseo industrial complex, well known for textile industry. In contrast, DMF was detected in only 20.4% and 12.9% of all the samples from the other two sites in Banwall and Siwha industrial complexes, respectively. This implies that sources of DMF should be strongly associated with textile industry. The mean concentration of DMF also appeared to be the highest in Seongseo site (5.95 ppb), followed by a residential site in Daegu (3.28 ppb), Banwall (0.88 ppb) and Siwha (0.55 ppb). In this study, we demonstrated the environmental significance of DMF in urban ambient air. To our knowledge, the DMF measurement introduced in this paper is the first case of an official report in Korea.

• 대한환경공학회지
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• 제31권2호
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• pp.147-152
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• 2009

본 연구에서는 톨루엔 계열 화합물로 오염된 환경에 대해 고정화한 유전자 재조합 균주 KG1206의 적용 가능성에 대해 조사하였다. 재조합 균주 KG1206은 직접 유도제인 m-toluate, benzoate 뿐만 아니라 톨루엔, 자일렌 이성질체가 간접 유도제로서 발광 활성을 나타낸다. 연구에 의해 결정된 고정화 프로토콜의 최적 조건은 다음과 같다: 균주 농도(1 : 1 (v/v)), 오염원 용액(인산염 완충액), 발광 측정에 필요한 비드 수(4개), 5가지 오염원에 대한 최대 발광 활성은 일반적으로 m-toluate > p-xylene > 톨루엔 > o-xylene > m-xylene 순으로 나타났다. 생물발광과 오염원 감소는 HPLC로 확인하였으며, 고정 균주에 의해 초기 5 mM m-toluate는 5시간 배양 후 약 48%의 감소율을 나타내었으며 계속 분해되는 경향이 관찰되었다. 알긴산 균주 고정화에 대한 본 연구 결과는 톨루엔 계열 화합물을 함유한 석유계 탄화수소에 오염된 특정 환경을 생물학적 모니터링에 유용한 방법으로 사용할 수 있을 것이다.

• 대한화학회지
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• 제37권3호
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• pp.317-326
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• 1993

변형된 ZSM-5 제올라이트 촉매에서 톨루엔의 n-프로필알코올에 대한 산촉매 반응이 조사되었고, 이알킬벤젠 이성질체들의 100$^{\circ}C$에서의 흡착 실험이 수행되었다. 4-프로필암모늄이온, 알루민산나트륨, 콜로이달실리카 등으로부터 수열반응에 의하여 ZSM-5가 합성되었으며, H-, K-, Sr-, P-Mg-HZSM-5, H-Y 및 H-모더나이트 등이 전통적인 방법에 의하여 만들어졌다. HZSM-5에서 톨루엔의 n-프로필알코올에 의한 주반응생성물은 크실렌, 프로필톨루엔 뿐만 아니라 에틸톨루엔을 포함하며, P-Mg-HZSM-5에서는 이알킬벤젠 이성질체중 높은 파라 선택성이 얻어졌다. 다양한 p-이성질체들의 확산계수는 1 ${times}$ 10$^{-10}$ cm$^2$/sec로 일정했으며 o-이성질체보다 m-이성질체가 10배 이상 느리게 나타났다. 이들 반응 및 흡착특성이 제올라이트의 세공구조에 의한 형상 선택성, 제올라이트의 산성도 등의 관점에서 해석되었다.

• 한국분무공학회지
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• 제23권4호
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• pp.185-191
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• 2018

Benzene, toluene, ethylbenzene and xylene (BTEX) were well known as ozone precursors from photochemical reactions and contribute to the formation of photochemical smog which pose health hazards. Also, some of these compounds directly affect the human health due to their toxicity such as benzene. In this study, BTEX ratios and correlation of $C_2$-benzenes (xylenes, ethylbenzene) in vehicle exhaust from recreational vehicle (RV) and multi-purpose vehicle (MPV) were characterized using a chassis dynamometer. VOCs were collected by tedlar bag and a GC/MS system was used for their quantification. Among all of the BTEX, toluene has the highest concentration(more than 30% in composition of BTEX). The average ratio of toluene to benzene emissions (T/B ratio=2.2) was found in vehicle exhaust. The average m,p-xylene/ethylbenzene and m,p-xylene/o-xylene ratios were 1.0 and 3.0 respectively. As a result, it showed a good correlation between the $C_2$-benzenes ($R^2=0.98{\sim}0.99$). In the future, it can be used as a marker for effect evaluation to atmospheric environment by vehicle exhaust.

• 한국물환경학회지
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• 제27권2호
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• pp.167-177
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• 2011

Oil이나 Gas생산시 발생하는 Produced water의 양은 미국 내에서만 연간 수십억 배럴에 육박한다. 이러한 Produced water의 재이용을 위한 첫 번째 과제는 유해 유기물질을 제거하는 것으로, 본 연구에서는 수중의 BTEX를 가스상태로 변화시킨 후 Vapor phase biofilter (VPB)로 분해, 제거 효능을 평가하였다. VPB 시스템은 짧은 기간의 시스템 shutdown에는 거의 영향을 받지 않는 것으로 나타났다. 그러나 주입 되는 농도가 Peak 형태를 가질때는 제거효능의 저하가 관찰 되었으며, 이중 Benzene이 가장 민감하게 반응하였다. 이를 위한 해결책으로 GAC로 충진된 Buffering Column이 사용되었으며, 이는 peak 형태의 유입농도 Profile을 완만한 형태로 buffering하는 역할을 하였다. 현장 적용을 통하여, 본 시스템이 Produced water내에 존재하는 용존 BTEX를 효과적으 로 제거할 수 있음을 확인하였다.

• Journal of Microbiology and Biotechnology
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• 제33권7호
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• pp.875-885
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• 2023

Volatile organic compounds such as benzene, toluene, ethylbenzene, and isomers of xylenes (BTEX) constitute a group of monoaromatic compounds that are found in petroleum and have been classified as priority pollutants. In this study, based on its newly sequenced genome, we reclassified the previously identified BTEX-degrading thermotolerant strain Ralstonia sp. PHS1 as Cupriavidus cauae PHS1. Also presented are the complete genome sequence of C. cauae PHS1, its annotation, species delineation, and a comparative analysis of the BTEX-degrading gene cluster. Moreover, we cloned and characterized the BTEX-degrading pathway genes in C. cauae PHS1, the BTEX-degrading gene cluster of which consists of two monooxygenases and meta-cleavage genes. A genome-wide investigation of the PHS1 coding sequence and the experimentally confirmed regioselectivity of the toluene monooxygenases and catechol 2,3-dioxygenase allowed us to reconstruct the BTEX degradation pathway. The degradation of BTEX begins with aromatic ring hydroxylation, followed by ring cleavage, and eventually enters the core carbon metabolism. The information provided here on the genome and BTEX-degrading pathway of the thermotolerant strain C. cauae PHS1 could be useful in constructing an efficient production host.

• 한국환경과학회지
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• 제32권6호
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• pp.403-417
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• 2023

In this study, we investigated the characteristics of Volatile Organic Compounds(VOCs) emission from painting and printing facilities in the Pyeongdong industrial complex in Gwangju. In addition, the objective was to understand the distribution characteristics of VOCs in the ambient air in industrial complexes affected by painting and printing facilities. The painting facility mainly emitted toluene, acetone, butyl acetate, 4-methyl-2-pentanone, ethyl acetate, 1-butanol, methyl ethyl ketone, m,p-xylene, o-xylene, 4-ethyltoluene, ethylbenzene, 3-ethyltoluene, and 1,2,4-trimethylbenzene. The main emission components in printing facilities were methyl ketone, ethyl acetate, acetone, 2-propanol, toluene, heptane, and butyl acetate. Ethyl acetate, toluene, 2-butanone, acetone, butyl acetate, 2-propanol, xylenes, and 4-methyl-2-pentanone were detected in the ambient air of the Pyeongdong industrial complex, consistent with the VOCs emitted by painting and printing facilities. The average concentration of seasonal TVOCs followed an order of winter > fall > spring > summer, whereas the concentrations of daytime and nighttime TVOCs were generally higher at night than those during the day, and the wind speed was greater during the day than it was at night. Based on a factor analysis of VOCs in the ambient air of Pyeongdong industrial complex, it is considered that organic solvents used in coating, printing, and electronics manufacturing facilities, as well as diesel vehicle emissions played a major role.

• 대한환경공학회지
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• 제36권7호
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• pp.498-505
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• 2014

본 연구는 대구광역시 산단지역 대기 중의 휘발성유기화합물 특성을 조사하였다. 산단지역은 비산단지역에 비해 톨루엔, 에틸벤젠, m,p-자일렌, o-자일렌 순으로 높은 농도차를 보였고, 벤젠과 클로로포름은 지역별로 뚜렷한 농도차가 없었다. 측정계절별로는 산단지역은 하고동저형을 보였다. 특히 화학물질 사용 영향으로 인해 산단지역은 측정요일별로는 평일이 휴일에 비해 높게 나타났고, 측정시간대별로는 가동시간을 포함한 오전, 오후 시간대가 상대적으로 높게 나타났다. VOCs 물질간의 상관성은 산단지역이 비산단지역에 비해 유의한 상관이 많았고, 기상인자와는 풍속이 VOCs와 음의 상관을 보였다.

• 환경영향평가
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• 제20권4호
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• pp.497-507
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• 2011

This research studied human health risk assessment of benzene from industrial complexes of Chungcheong Province (Seosan industrial complex) and Jeonla Province (Iksan industrial complex and Yeosoo industrial complex). The residents near the industrial complexes areas can be often exposed to volatile organic compounds (e.g., benzene, toluene, xylenes) through a number of exposure pathways, including inhalation of the organic pollutant via various environmental matrices (air, water and soil), contaminated water, and soil intake. Benzene is well known to be a common carcinogenic and toxic compound that is produced from industrial and oil refinery complexes. In this study, a number of samples from water, air, and soil were taken from the residential settings and public school zones located near the industrial complex sites. Based on the carcinogenic risk assessment, the risk estimates were slightly above $10{\times}10^{-6}$ at all three industrial sites. According to deterministic risk assessment, inhalation was the most important route. The distribution of benzene in the environment would be dependent on vapor pressure, and the physical property influencing the extent of the potential risks. Non-carcinogenic risk assessment of benzene shows that the values of Hazard Index(HI) were much lower than 1.0 at all industrial complexes. Therefore, benzene was not a cause of concern in terms of non-carcinogenic risk posed to the residents near the sites. When compared to probabilistic risk assessment, the CTE(central tendency exposure) cancer risk values of deterministic risk assessment were close to the mean values predicted by the probabilistic risk assessment. The RME(reasonable maximum exposure) values fell within the range of 95% to 99.9% estimated by the probabilistic risk assessment. Since the values of carcinogenic risk assessment were higher than $10{\times}10^{-6}$, further detailed monitoring and refined risk assessment for benzene may be warranted to estimate more reliable and potential inhalation risks to receptors near the industrial complexes.