• Analytical Science and Technology
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• v.19 no.6
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• pp.553-558
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• 2006

In this study, an attempt was made to measure uncertainties involved in the VOC analysis for the VOC working standards prepared by a dilution technique using Tedlar bags. For this purpose, VOC standard gases of benzene, toluene, xylene, and styrene were prepared at four different concentrations (4, 8, 20, and 40 ppb). These standard samples were then loaded on to the GC system equipped with air server/thermal desorption (AS/TD) system. Each of these four standard concentrations was analyzed individually to derive their respective calibration results. These calibration data sets were then compared across four different compounds. According to this comparison, differences in calibration patterns were moderately insignificant within the selected concentration range of 4~40 ppb. It was also observed that the loss of styrene standard was fairly high compared to other VOCs investigated simultaneously. The results of our study suggest that the analytical uncertainty associated with the preparation of VOC starndard gas using a dilution technique can be assessed in a fairly reasonable manner for samples with a narrow concentration range.

• Korean Journal of Environmental Biology
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• v.25 no.3
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• pp.191-196
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• 2007

Indoor air differs from outdoor atmosphere since it contains chemical and physical contaminants from building materials. This study deals with the biological effects of volatile organic compounds (VOCs) released from synthetic fiber carpet materials. One group of Tradescantia inflorescence was exposed to VOCs from the carpet sample in the environmental test chamber, while the other inflorescence group was exposed to a TO-14 standard gas mixture (1 ppm) for comparison. After the exposure, VOCs from the carpet were analysed by the desorber/GC/MS method, and micronuclei in the pollen mother cells of Tradescantia were scored under a microscope $({\times}400)$ to evaluate the genotocixicity induced by the exposure to VOCs. The chemical analysis confirmed that a total of 12 VOCs were released from the carpet materials, among which stylene $(71.9{\mu}g\;m^{-3})$ and toluene $(49.6{\mu}g\;m^{-3})$ were in the highest concentration. Twenty four hours of exposure to VOCs from the carpet in the environmental test chamber resulted in a micronucleus frequency as high as $7.73{\pm}0.75MCN$ per 100 tetrads, which was similar to that induced after exposure to the TO-14 standard gas mixture (1 ppm) for 4 hours. Meanwhile, two hours of exposure to the standard gas mixture did not cause a significant increase in the genotoxicity compared to the spontaneous micronucleus frequency. This result indicates that exposure for a long time to the air contaminated with VOCs from the carpet materials causes a genotoxic effect. The biological-chemical combination analyses in the study proved to be an effective tool for monitoring the indoor air contaminants.

• Korean Journal of Food Science and Technology
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• v.36 no.6
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• pp.919-923
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• 2004

Effects of adding 0, 2, 4, 6, and 8% freeze-dried kimchi powder (FDKP) on kimchi snack quality were examined. Headspace volatile compounds of 4% FDKP snack, receiving highest overall preference in sensory evaluation results, were analyzed, and 26 compounds were identified, including 13 aldehydes, 3 sulfides, a ketone, an acid, a terpene, and 7 other compounds. Pearson correlation analyses were carried out to determine a correlation between the concentration of FDKP and the amount of each volatile compound. Acetaldehyde, propanal, dimethyl sulfide, dimethyl disulfide, acetic acid, and d-limonene showed correlation coefficients above 0.90; selective ion move (SIM) analysis also showed above 0.97 for highly correlated compounds. Results suggest that these compounds can be used as indicators fur kimchi flavor of FDKP snack.

• Culinary science and hospitality research
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• v.19 no.3
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• pp.105-115
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• 2013

Maillard reaction flavors had been tried by using krill hydrolysate and precursors in order to develop Teriyaki sauce with the reaction flavors. Also, the study for applying krill to Teriyaki sauce had been tried by using krill instead of eel bones. To make boiled-type and grilled-type reaction flavors, krill hydrolysate was used with other precursors such as serine, glucose and glucosamine. In the dynamic analysis of headspace volatile compounds, 20 mL reaction flavor was analyzed by the combined system of purge & trap, automatic desorber, gas chromatography and mass selective detector. Three kinds of Teriyaki sauce were developed with reaction flavor, krill and eel bones, and their products were evaluated by 10 items of cooked vegetables, cooked potatoes, boiled shrimp, grilled shrimp, fishy smell, pungent aroma, burned smell, sweety aroma, chemical smell, mud smell and preference. In the results of headspace analysis, 35 and 33 volatile compounds were identified from grilled-type and boiled-type reaction flavors. Grilled-type had sulfur-containing, aliphatic compounds, alcohols, ketones, pyrazines, and other aromatic compounds, and grilled-type had aldehydes, furans, other nitrogen-containing compounds. In the sensory evaluation of Teriyaki sauce, the items of roasted shrimp and sweety aroma showed significant differences for grilled-type application to Teriyaki sauce. The above results show the possible application of grilled-type reaction flavor to Teriyaki sauce.

• Korean Chemical Engineering Research
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• v.48 no.2
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• pp.244-252
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• 2010

The objective of this study is to assess feasibility of simultaneous analysis for trace multi-components odorous and volatile organic compounds using a Triple-bed adsorbent tube with a thermal desorber and GC-MS. Triple-bed adsorbent tube is 3 bed packed Tenax-TA with small amount of Carbopack B and Carbosieve SIII in order of adsorption strength in a tube. The operating conditions of GC-MS was possibly able to and effectively detect high volatile and low molecular weight compounds at the mass range of 20~350 m/z using a below impurity 1ppm of Helium carrier gas, of which quantitatively analyzed by target ion extracts. According to the experiment, $C_1{\sim}C_5$ of 14 components; sulfur containing compounds(2), ketones(2), alcohols(4) and aldehydes(6) were simultaneously analyzed with recoveries of 99%, and good repeatability and linearity. High volatile and low molecular weight compounds such as methyl alcohol and acetaldehyde can be safely quantified with high recovery at a condition of 50mL/min of flow rate, below 2L of adsorption volume, and 45% of relative humidity. Target ion extract can also simultaneously quantify multicomponents with odorous and volatile organic compounds in an occasion of piled up two peaks.

• Environmental Analysis Health and Toxicology
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• v.17 no.3
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• pp.197-205
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• 2002

Volatile organic compounds (VOCs) are an important public health problem throughout the world. Many important questions remain to be addressed in assessing exposure to these compounds. Because they are ubiquitous and highly volatile, special techniques must be applied in the analytical determination of VOCs. Personal exposure measurements are needed to evaluate the relationship between microenvironmental concentrations and actual exposures. It is also important to investigate exposure frequency, duration, and intensity, as well as personal exposure characteristics. In addition to air monitoring, biological monitoring may contribute significantly to risk assessment by allowing estimation of absorbed doses, rather than just the external exposure concentrations, which are evaluated by environmental and personal monitoring. This study was conducted to establish the analytic procedure of VOCs in air, blood, urine and exhaled breath and to evaluate the relationships among these environmental media. The subjects of this study were selected because they are occupationally exposed to high levels of VOCs. Environmental, personal, blood, urine and exhalation samples were collected. Purge ＆ trap, thermal desorber, gas chromatography and mass selective detector were used to analyze the collected samples. Analytical procedures were validated with the“break through test”, 'quot;recovery test for storage and transportation”,“method detection limit test”and“inter-laboratory QA/QC study”. Assessment of halogenated compounds indicted that they were significantly correlated to each other (p value < 0.01). In a similar manner, aromatic compounds were also correlated, except in urine sample. Linear regression was used to evaluate the relationships between personal exposures and environmental concentrations. These relationships for aromatic and halogenated are as follows: Halogen $s_{personal}$ = 3.875+0.068Halogen $s_{environmet}$, ($R^2$= .930) Aromatic $s_{personal}$ = 34217.757-31.266Aromatic $s_{environmet}$, ($R^2$= .821) Multiple regression was used to evaluate the relationship between exposures and various exposure deter-minants including, gender, duration of employment, and smoking history. The results of the regression model-ins for halogens in blood and aromatics in urine are as follows: Halogen $s_{blood}$ = 8.181+0.246Halogen $s_{personal}$+3.975Gender ($R^2$= .925), Aromatic $s_{urine}$ = 249.565+0.135Aromatic $s_{personal}$ -5.651 D.S ($R^2$ = .735), In conclusion, we have established analytic procedures for VOC measurement in biological and environmental samples and have presented data demonstrating relationships between VOCs levels in biological media and environmental samples. Abbreviation GC/MS, Gas Chromatography/Mass Spectrometer; VOCs, Volatile Organic Compounds; OVM, Organic Vapor Monitor; TO, Toxic Organicsapor Monitor; TO, Toxic Organics.

• Analytical Science and Technology
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• v.17 no.2
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• pp.130-144
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• 2004

Recently, the air pollution in A and B industrial area has become one of the most important issues, then 60 VOCs in the area were measured using a highly sensitive method. The VOCs were adsorbed onto Carbotrap using air sampler and subsequently desorbed by a thermal desorber system into gas chromatograph-mass spectrometry (TDS-GC-MS). The peaks of all compounds had good chromatographic properties and offered very sensitive response for the EI-MS (SIM). Method detection limits (MDL) ranged from 0.01 to 0.1 ppt(v/v), and linearities of calibration curves were over 0.995. We analyzed total 90 atmosphere air samples of A and B industrial complex using the method. Benzene, toluene, ethylbenzene, xylene, n-hexane, fluorotrichloromethane, carbon tetrachloride, 1,2-dichloroethane, 1,1,1-trichloroethane, trichloroethylene, tetrachloroethylene, styrene, 1,3,5-trimethylbenzene, 1,2,4-trimethylbenzene, sec-butylbenzene and naphthalen were identified as the major compounds in the air, and their average concentrations were 0.81, 5.02 1.30, 3.0, 0.81, 37.9, 0.07, 0.15, 0.15, 0.79, 0.06, 0.33, 0.03, 0.12, 0.23, and 0.35 ppb(v/v), respectively. The concentrations of VOCs were low in summer and high in fall or winter. When the concentrations detected in air compare with WHO's norm, no case exceed it.

• Analytical Science and Technology
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• v.22 no.3
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• pp.191-200
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• 2009

The aim of this study was to evaluate and establish of emission test method for liquid phase building materials such as paint, adhesive, sealant by emission cell. A small-scale emission chamber and emission cell were used to evaluate emission of TVOC from paint, adhesive, sealant. The quantity of TVOC emission were measured by a gas chromatography/mass spectrometry (GC/MS). Background concentration of TVOC was below $10{\mu}g/m^3$ in the emission chamber and cell. Air tightness and recovery in chamber and cell showed good results. The recovery of thermal desorber for toluene and n-dodecane were about 120%. The repeatability of response factor and retention time in GC/MS below 30%. The method detection limit of VOCs ranged 0.04~8.82 ng. The concentration of TVOC emission using emission cell was 1.35~1.41 times higher than emission chamber. The correlation of TVOC emission using chamber and cell method was significantly high (r=0.91~0.97).

• Analytical Science and Technology
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• v.28 no.3
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• pp.246-254
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• 2015

From 2013 to 2014, volatile organic compounds (VOCs) were analyzed to determine biogenic volatile organic compounds (BVOCs) and anthropogenic volatile organic compounds (AVOCs) at eight sites in Mt. Mudeung and one site in downtown, by using a GC/Mass-ATD (automatic thermal desorber). The concentration of terpene noted as biogenic volatile organic compounds at Pungamjeong (PA), in a forest of Chamaecyparis obtusa, was 821 pptv, which was the highest among the eight sites. This value was followed by Wonhyogyegok (WH: 785 pptv), Norritzae (NZ, coniferous forest: 679 pptv), Dongjeokgol (DJ, mixed species forest: 513 pptv), Jangbuljae (JB, Abies koreana: 476 pptv), and Seinbongsamgerri (SS, pine trees: 464 pptv). 11~15 species of terpene was detected in the forest depending on the site. At PA in May, α-pinene showed the highest value, occupied 20% of terpene followed by coumarin, sabinene, phellandrene, myrcene, borneol, eucalyptol, β-pinene, cymene, δ-limonene, γ-terpinene, camphor, camphene, and mentol in the order. The mean concentrations of AVOCs were 0.74~2.52 ppbv in the forests and 3.14 ppbv in the downtown area. From May to July, the AVOCs ratios of the downtown to each forest were 1.9~4.0. Among 10 species of AVOCs, the sum of toluene and benzene was 2.34 ppbv and occupied 75%. In June, the ratios of toluene were 44.1% at DJ site and 53.1% at JW site (downtown). The BVOCs showed a positive correlation with the AVOCs at the forest sites (r = 0.328), which was statistically insignificant (p = 0.184).

• Analytical Science and Technology
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• v.26 no.4
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• pp.268-275
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• 2013

Many kinds of liquid spray products are used in livelihood activities these days. Spray products can be distinguished by the target to be sprayed (like into the air or on human skin (body)). Because human can be exposed to volatile organic compounds (VOC) emitted from spray products, some considerations on safety or hazard of spray products should be needed. In this study, emission characteristics of VOCs were investigated against 10 types of liquid spray products (6 skin spray and 4 air spray products). The concentrations of benzene and toluene were determined by gas chromatography/mass spectrometry (GC/MS) equipped with a thermal desorber (TD). Their average concentrations from 6 skin spray products exhibited$ 5.64{\pm}1.95$ ($mean{\pm}S.D$) and $8.52{\pm}2.89$ ppb(w), respectively. In contrast, those of 4 air spray samples had $7.30{\pm}1.31$ and $7.19{\pm}1.78$ ppb(w), respectively. If liquid contents in spray samples are completely vaporized in one cubic meter (1 m3) after spraying for 10 seconds, their mean concentrations of skin spray products are $31.7{\pm}8.80$ (benzene) and $50.5{\pm}17.1{\mu}g/Sm^3$ (toluene). In contrast, those of air spray products are $24.0{\pm}4.30$ (benzene) and $23.6{\pm}5.83{\mu}g/Sm^3$ (toluene). The estimated concentration levels of benzene from two types of products (31.7 and $24.0{\mu}/Sm^3$) exceeded the Korean atmospheric environmental guideline ($5{\mu}g/Sm^3$). The results of this study thus suggest that some measures should be made to reduce or suppress the contents of VOC in spray products.