• 한국물환경학회지
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• 제37권6호
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• pp.510-519
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• 2021

Volatile Organic Compounds (VOCs) in sediments, which can cause human health problems, have been monitored in Korea since 2014. Measured VOC concentrations can be affected by matrix type and the volatility of target substances. In this study, (1) VOCs volatility and the influence of matrix interference were confirmed, and (2) internal standards (IS) method was applied to improve analytical method. For these purposes, method detection limit (MDL), calibration linearity, precision and accuracy of VOCs were compared in various matrices using the IS. Some of VOCs in sediments showed different peak areas and reduced rates compared to water matrix. It was suggested that adsorption properties of sediments hindered the migration to vapor during heat pretreatment in headspace method. A calibration curve was created in clean sand. Recovery rates for the calibration curve method and IS applying method were 64.1~83.1% and 99.1~119.3%, respectively. Relative standard deviations ranged from 11.1% to 21.6% for the calibration curve method and those for IS ranged 4.7% to 13.7%. In case of real sediment, calibration curve and 1,2-Dichlorobenzene-d4 (ODCB) among IS were not suitable. The average recovery rate of Fluorobenzene (FBZ) increased by 56.4% and Relative Standard Deviation (RSD) by 4.7%. However, the recovery rate was increased in the samples with large values of igniting intensity. This study confirmed that influence of the matrix of VOCs in sediment, and addition of IS materials improved precision and accuracy. Although IS corrects volatilization and adsorption, it is recommended that more than two types of IS should be added rather than single.

• 한국환경과학회지
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• 제17권1호
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• pp.45-56
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• 2008

This study was to assess the lifetime cancer and non-cancer risk of exposure of worker and user at public facilities in Korea to volatile organic compounds (VOCs). We measured the concentrations of two aldehydes and five VOCs in indoor air at 424 public buildings that 8 kinds of public facilities (70 movie theaters, 86 offices, 86 restaurants, 70 academies, 22 auditoriums, 30 PC-rooms, 30 singing-rooms and 30 bars) all over the country. There were estimated the human exposure dose and risks with averages of the using-time and frequency for facility users and office workers, respectively. Carcinogens (formaldehyde, acetaldehyde, and benzene) were estimated the lifetime excess cancer risks (ECRs). non-carcinogens (toluene, ethylbenzene, xylene, and styrene) were estimated the hazard quotients (HQs). The average ECRs of formaldehyde and benzene for facility worker and user were $1{\times}10^{-3}{\sim}1{\times}10^{-4}\;and\;1{\times}10^{-4}{\sim}1{\times}10^{-5}$ level, respectively, in all facilities. HQs of four non-carcinogens did not exceed 1.0 for all subjects in all facilities. The estimated ECRs for restaurant and auditorium were the highest, and the PC-room and bar were the next higher facilities. Furthermore, people in a smoking facility had the highest cancer risk. Higher ECRs of formaldehyde and benzene were observed in indoor smoking facilities such as restaurant and auditorium. Higher HQs of toluene and xylene were observed at the restaurant and office building.

• 한국환경과학회지
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• 제18권5호
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• pp.479-487
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• 2009

Because of the building is made airtight, Indoor Air Quality(IAQ) is go from bad to worse. There are many source of indoor pollution in any home. These include irritation of the eyes, nose, and throat, headaches, dizziness, and fatigue. Such immediate effects are usually short-term and treatable. In this study was measured and analyzed VOCs exposure levels and characteristic of Indoor air pollutant from new apartments in Korea. VOCs were measured indoor pre-residential and residential in new apartment and analyzed GC/MS. The concentration levels of indoor respirable TVOC were found to be higher than those of outdoor TVOC for new apartments. Before occupation, the average indoor and outdoor concentrations were 1498.61 $ug/m^3$ and 468.38 $ug/m^3$, respectively. After being occupied, the average indoor and outdoor concentration were 847.04 $ug/m^3$ and 102.84, respectively. The concentrations of TVOC in new apartments before occupation were shown in the order of Toluene(328.12 $ug/m^3$) > m,p-Xylene(163.67 $ug/m^3$) > Ethy1benzene(80.70 $ug/m^3$>o-XYlene (67.04$ug/m^3$). In addition, the TVOCs concentrations after occupation were also found in the order of Toluene (272.28 $ug/m^3$) > m.p-Xylene(121.79 $ug/m^3$) > Ethylbenzene(53.92 $ug/m^3$)>O-Xylene(24.94 $ug/m^3$). As a result, the concentrations of VOCs in new apartment houses were shown to be affected by indoor environment according activity patterns. So new apartments need to be controled in indoor air quality so that the residents can have more comfortable and healthier living environment.

• 상하수도학회지
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• 제30권6호
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• pp.673-682
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• 2016

In this study, we investigated influent and effluent water pollutants in 53 Public Sewage Treatment Works (PSTWs) where industrial wastewater or landfill leachate is combined four times for two years from 2014 to 2015. Also, we analyzed the characteristics of heavy metals and volatile organic carbons at influent and effluent of these PSTWs caused by sewage treatment combined with industrial wastewater or landfill leachate. As a result, six heavy metals such as barium, copper, iron, manganese, nickel and zinc, and four volatile organic carbons (VOCs) including phenols, di(2-)ethylhexyl phthalate (DEHP), formaldehyde and toluene were observed above detection limits in most of PSTWs. Also, it was revealed that six heavy metals such as hexavalent chromium, mercury, cadmium, chromium, nickel and selenium, and four VOCs including 1,1-dichloroethylene, vinyl chloride, naphthalene, and epichlorohydrin were observed more frequently according to precipitation. As a result of reviewing the monitoring data on "Water Quality Monitoring Networks" in lower watersheds of PSTWs, both heavy metals and VOCs were below detection limits, indicating that the effluent water had little influence on the watershed. Nevertheless for the better management of influent and effluent pollutants in PSTWs, it is necessary to establish the advanced management plans for water pollutants in PSTWs, which include a list of priority substances management, monitoring plans, and guidelines for industrial wastewater and landfill leachate combined in PSTWs.

• 한국대기환경학회지
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• 제25권6호
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• pp.523-538
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• 2009

Recently, there has been a keen demand for real-time automatic monitoring of VOCs not only in Korea but other developed countries. We carried out this study to evaluate and to optimize the performance of a continuous automatic monitoring system for hazardous VOCs (HVOCs) in the ambient atmosphere, using an on-line GC system. The online system normally consisted of a Nafion dryer prior to a cold trap of an automatic thermal desorption apparatus and a GC system equipped with two detectors, i.e. PID and ECD. Preliminary tests conducted to check out any contamination of the system revealed an evidence of significant artifact formation of benzene, and it was found that the Nafion dryer (even brand new one) is the source of the benzene artifact. Thus, all the subsequent experiments in this study was carried out inevitably by removing the Nafion dryer. The on-line GC method was investigated with a variety of QC/QA performance criteria such as repeatability, linearity, lower detection limits, and accuracy. In order to find out the best operating condition for the on-line GC system, three different types (in terms of adsorption strength) of cold trap combinations were tested, i.e. (i) Tenax-TA and Carbopack-B combination (weak and hydrophobic); (ii) Tenax-TA, Carbopack-X and Carboxen-1000 combination (strong and hydrophilic); and (iii) Tenax-TA and Carbopack-X combination (medium and hydrophobic/hydrophilic). The USEPA TO-17 manual method was selected as a reference method to evaluate the performance of the on-line method. A series of experiments revealed that the system performance was superior to others when a cold trap packed with hydrophilic adsorbents (Tenax-TA/Carbopack-X/Carboxen-1000 combination) was used and operated at $25^{\circ}C$. However, the system with a cold trap packed with a combination of Tenax-TA and Carbopack-X is more recommended for field applications since the carboxen-1000 adsorbent is too sensitive to water vapor, and hence the performance of the system might be very unstable to humid samples or during rainy days. Furthermore, the precision and accuracy criteria of the Tenax-TA/ Carbopack-X combination were generally compatible with the triple adsorbents cold trap. The continuous automatic monitoring method is, thus, considered very useful to real-time monitoring to understand the variations of VOCs concentrations in ambient air, as it adopts much simpler procedures in sampling, analysis, and data integration steps than manual monitoring methods. However, it should be noted that there is a high possibility of benzene artifacts formation through the Nafion dryer, which is often installed to remove water vapor in air samples before being adsorbed onto the cold trap. Therefore, if a Nafion dryer is used in any studies of monitoring VOCs, the benzene contamination should be carefully examined before carrying out obtaining the data.

• 분석과학
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• 제16권5호
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• pp.407-417
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• 2003

본 연구에서는 중형 규모의 매립장지역을 중심으로 환경대기 및 배출가스 중의 VOC농도를 관측하였다. 특히 배출가스에 대해 15가지 VOC성분을 GC-PID방식으로 분석하고, 이를 이용하여 15가지 성분의 탄소성분의 조성에 미치는 기여도를 평가하였다. 본 연구의 결과에 의하면, 배출가스 중의 VOC는 수 십 ppm 수준으로 일반 대기 중의 농도와 1천배 가까운 차이를 보여주었다. 따라서 배출가스와 환경대기 중의 VOC 농도에는 상당한 수준의 차이가 존재하는 것을 확인할 수 있었다. 이를 자료를 이용하여, 배출량을 산정한 결과 15가지 VOC성분과 전체 비메탄계 탄화수소 (NMHC)의 배출량은 연간 8.6과 103 ton으로 계산되었다. 특히 이들 15개 VOC성분 중에서 BTEX의 기여도가 절대적으로 중요하다는 것을 확인할 수 있었다.

• 대한환경공학회지
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• 제27권5호
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• pp.468-475
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• 2005

휘발성 유기화합물(VOCs)의 제거를 위한 담체충진형 바이오필터법은 운전이 용이하고 처리비용이 낮다는 장점에도 불구하고 낮은 운전성능과 막힘현상등의 문제를 안고 있다. 이에 대한 대안으로 계면활성제로 형성된 거품을 사용해 VOCs의 물질전달율과 분해효율을 향상시킨 미생물반응기(BFR)가 제안되었다. 본 연구는 VOCs 저감기술로서 BFR의 적용가능성을 확인하기 위하여 수행되었다. 우선, BFR에 사용될 계면활성제를 선정하기 위해, 4종류의 계면활성제를 대상으로 회분실험을 수행하였으며, 실험결과 TritonX-100이 미생물의 생분해도에 미치는 영향이 가장 적어 BFR에 적용하기 적합한 계면활성제로 판명되었다. 선정된 계면활성제를 BFR에 첨가하고, 반응기 내에 유입되는 가스의 체류시간과 톨루엔 유입부하량을 변화시키면서 반응기의 운전성능을 평가하였다. 가스체류시간이 0.5분에서 2분으로 증가하면서 반응기의 톨루엔 분해율도 50%에서 80%로 증가하였다. 그러나 톨루엔 유입부하량이 $38\;g/m^3/hr$에서 $454\;g/m^3/hr$으로 증가하면서 톨루엔 분해율은 70%에서 20%로 감소하였다. 본 실험에서는 BFR의 최대분해능은 $108\;g/m^3/hr$로 나타나 기존 담체 충진형 바이오필터에 비해 높았으며, 따라서 BFR 시스템이 기존의 담체를 이용하는 생물학적 VOCs 저감기술에 대한 대안으로서 가능성이 있음을 알 수 있었다. 하지만, 높거나 낮은 가스유속에서 거품이 안정적으로 발생하지 않는 점 등은 여전히 해결해야할 과제로 남아있다.

• 한국대기환경학회지
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• 제26권1호
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• pp.77-84
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• 2010

The diffusion and partition coefficients of polyurethane foam (PUF) are estimated using a microbalance experiment and small chamber test. The microbalance is used to measure sorption/desorption kinetics and equilibrium data. When the diffusion condition is controlled in the chamber of the sample, interactions between volatile organic compounds (VOCs) and PUF can lead to the estimation of a relatively homogenous rate of mass transfer in the interiors and surfaces of PUF. The estimates of the material/air partition coefficient (K) and the material-phase diffusion coefficient (D) are shown to be independent of the concentrations of VOCs. This approach, if applied to a diffusion-controlled or physically-based model, can facilitate more precise prediction of their source/sink behavior. Although further research and more rigorous validation is needed, an emission model applied with the diffusion and partition coefficients from this research holds promise for the improvement of reliability in predicting the behavior of VOCs emitted from porous building materials by D and K.

• 환경생물
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• 제25권3호
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• pp.191-196
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• 2007

실내 공기는 대기와는 달리 실내 건축 자재에서 유래된 물질로 오염될 수 있다. 본 연구는 실내자재인 카펫에서 방출되는 휘발성 유기화합물의 생물학적 영향을 평가하기 위하여 수행되었다. 카펫과 자주달개비 BNL 4430 꽃차례를 환경노출시험용기에 넣고 일정시간 노출을 실시하였고 흡착관의 VOCs에 대한 화학분석을 실시하였다. 화학분석결과 카펫에서는 12종의 VOCs가 방출되는 것이 확인되었으며 이중 스틸렌$(71.9{\mu}g\;m^{-3})$과 톨루엔$(49.6{\mu}g\;m^{-3})$의 농도가 높았다. 환경노출시험용기에서 카펫에서 방출되는 VOCs에 24시간 노출된 자주달개비 실험군의 미세핵 빈도는 100사분자 당 $7.73{\pm}0.75MCN$으로서 TO-14 표준혼합기체 1ppm에 4시간 노출된 실험군의 미세핵 빈도인 $7.31{\pm}0.70$와 유사한 높은 값을 나타내었다. 반면 표준혼합기체 1ppm에 2시간 노출된 실험군의 경우 미세핵 자연발생 빈도와 유사한 수준을 보였다. 이 같은 결과로부터 카펫에서 방출된 휘발성 유기화합물이 함유되어 있는 실내공기에 장시간 노출될 경우 생물유전독성이 유발된다는 것이 확인되었다. 본 연구에 적용한 생물-화학 병용분석 기법은 실내 공기오염의 생물학적 감시에 매우 효율적임이 입증되었다.

• 한국환경보건학회지
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• 제45권2호
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• pp.142-153
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• 2019

Objectives: The aim of this study was to determine environmental chemical exposure related to residential and personal lifestyle characteristics in the adult Korean population. The observations of this study can provide information useful for developing reduction approaches for exposure to chemicals among the general adult population. Methods: The second stage of the Korean National Environmental Health Survey (KoNHES) was conducted from 2012 to 2014, with 6,478 persons participating. Using the results of the survey, the relationship between exposure levels of heavy metals and organic chemicals and exposure factors, e.g. residential and personal lifestyle characteristics, were analyzed. Results: The exposure levels of VOCs and PAHs were significantly lower in participants living at a distance of more than 100 m from roads versus living closer to roads. Home ventilation lowered VOC and PAH exposure but did not lower chemical exposure from household products. Use of public transportation showed lower exposure to heavy metals, VOCs, and PAHs. Current smoker was significantly higher for levels of heavy metals, VOCs, and PAHs, and the exposure trend was similar for current drinkers. Physical activity was related with higher exposure to phthalates and environmental phenols. Conclusion: Our observations based on a nationally representative population for Korea show that exposure to chemicals varies by residential and personal lifestyle, and this should be considered for developing appropriate mitigation measures and policies. Given the health concerns surrounding environmental chemicals, it is necessary to develop comprehensive measures to reduce chemical exposure.