• Journal of the Korean Wood Science and Technology
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• v.34 no.4
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• pp.22-30
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• 2006

The volatile organic compound (VOC) Analyzer is a portable device to measure the four main aromatic hydrocarbon gases: toluene, ethylbenzene, xylene and styrene. With the VOC Analyzer, a semiconductor gas sensor eliminates the need for the carrier gas which is required for conventional gas chromatographs. In addition, since the semiconductor gas sensor is supersensitive to gas components, it is not necessary to use a conventional gas concentrator or other complicated equipment. Compared with other measurement methods, the VOC analyzer is useful for measuring toluene, ethylbenzene, xylene and styrene in wood-based panel because of its ease in obtaining field results and repeating the test. The VOC Analyzer primarily measures four VOC in the air. In this study, we designed a test method of VOC measurement for particle board. A specimen was sealed in 3L polyester bag, after 96hours we could measure maximum VOC emission level that is a stabilized VOC Value. For easy, fast and economic testing of TVOC emission from wood-based panel, we developed the test method with the VOC Analyzer. The VOC Analyzer is expected to gain widespread use in the manufacturing field where a quick and easy test for VOC emission from wood-based panel is required. Furthermore, the VOC Analyzer promises to become an easier, faster and more economic technique than the currently used standard methods.

• Analytical Science and Technology
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• v.18 no.6
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• pp.552-558
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• 2005

A type of dimethyl sulfide gas CRM in the ppb level was developed for the analysis of trace-level odorous gas in environmental atmosphere. The concentration of dimethyl sulfide ($(CH_3)_2S$) was 10 umol/mol level in the cylinder filled with nitrogen, 1500 psi. And the variability of the concentration for 3 years was about 0.1% due to the adsorption or instability of $(CH_3)_2S$. The gas standards produced simultaneously in 4 bottles and examined by GC-FID were shown with 0.4%, reproducibility of preparation and 0.25%, standard uncertainty due to weighing and purity. The relative expended uncertainty of 1.1% (95% of confidence level, k=2) was assigned to the certified value of 10 umol/mol level of $(CH_3)_2S$ after quantitative evaluation on the purity, mixing, weighing, analysis, adsorption and stability of dimethyl sulfide gas.

• Analytical Science and Technology
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• v.35 no.3
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• pp.116-123
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• 2022

Polymer bags, metallic canisters, and glass bottles have been used as containers for analyzing the volatile organic compounds (VOCs) in air. In this study, various sampling containers were compared to investigate the short-term stability of VOCs, that is, from the time they are sampled to the time they are analyzed. Polyvinyl fluoride (PVF), polypropylene (PP), polyester aluminum (PE-Al) bags, canisters, and glass bottles were used as sample containers. A 100 nmol/mol standard gas mixture of benzene, toluene, ethylbenzene, m-xylene, styrene, and o-xylene was used for the VOC comparison. Changes in the concentrations of samples stored for 10~20 day in each container were measured using a thermal desorption-gas chromatograph-flame ionization detector (TD-GC-FID). As a result, VOCs stored in a canister and two kinds of amber glass bottles have shown immaterial decreases in concentration in one week, and more than 80 % of the initial concentration was maintained for two weeks. In the case of polymer bags, the concentration of all VOCs, except benzene and toluene, were remarkably decreased below 70% of the initial concentration in one day. Particularly, ethylbenzene, xylene, and styrene have shown dramatic decreases in concentration below 30 % of the initial concentration in all polymer bags in one day.

• Analytical Science and Technology
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• v.19 no.6
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• pp.498-503
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• 2006

A type of dimethyl disulfide gas CRM in the ppb level was developed for the analysis of tracelevel odorous gas in environmental atmosphere. The concentration of dimethyl disulfide($(CH_3)_2S_2$) was $10{\mu}mol/mol$ level in the cylinder filled with nitrogen, 1500 psi. And the variability of the concentration for 2 years was about 0.14% due to the adsorption or instability of $(CH_3)_2S_2$. The gas standards produced simultaneously in 4 bottles and examined by GC-FID were shown with 0.4%, reproducibility of preparation and 0.25%, standard uncertainty due to weighing and purity. The relative expended uncertainty of 1.1%(95% of confidence level, k=2) was assigned to the certified value of $10{\mu}mol/mol$ level of $(CH_3)_2S_2$ after quantitative evaluation on the purity, mixing, weighing, analysis, adsorption and stability of dimethyl sulfide gas.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.10 no.1
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• pp.126-146
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• 2000

To develop and evaluate formaldehyde measurement method using 2,4-dinitro-phenylhydrazine (2,4-DNPH) coated sampler and gas chromatography, laboratory test and field test were conducted. Results of this study are as follows. Limit of detection(LOD) of measurement methods, HPLC-UVD, GC-NPD and GC-FID, is $0.008{\mu}g/m{\ell}$ $0.060{\mu}g/m{\ell}$, $0.472{\mu}g/m{\ell}$ respectively. Coefficiency of measurement methods, HPLC-UVD, GC-NPD and GC-FID, is 0.008, 0.009, 0.020 respectively. Desorption efficiency of sep-pak xposure aldehyde sampler and sorbent sample tube is 1.05(range : 0.99 - 1.12), 1.02(range : 0.99 - 1.06) respectively. Samples of sorbent sample tube and sep-pak xposure aldehyde sampler turned out to be stored at refrigerator, according to storage test results. Measurement methods of HPLC-UVD, GC-NPD, GC-FID, according to results of precision for the combined sampling and analytical procedure, became acceptable to OSHA evaluation standard. Field test using exposure chamber met the NIOSH overall uncertainty recommendation(less than 25%). Overall uncertainty of Sepak-HPLC(UVD), Tube-GC(NPD), Tube-GC(FID) is 11.0% - 17.0%. Consequently gas chromatography(GC-NPD, GC-FID) and high performance liquid chromatography(EPA TO-11) using 2,4-DNPH coated sampler for formaldehyde measurement turned out to be suitable to measure personal formaldehyde exposure at workplaces.

• Analytical Science and Technology
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• v.14 no.2
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• pp.147-158
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• 2001

Polychlorinated dibenzo-p-dioxins(PCDDs), dibenzofurans(PCDFs), and biphenyls(PCBs) were analyzed by HRGC/HRMS in human blood samples from the Siwha industrial area in Korea. The PCDD/F and PCB concentrations in workers were higher than those in residents. The average TEQ concentrations of PCDD/Fs in workers and residents were 40.3 pg I-TEQs/g lipid and 16.6 pg I-TEQs/g lipid, respectively, and the total PCB concentrations were 174.1 ng/g lipid and 151.0 ng/g lipid, respectively. When applied to principal component analysis, the PCDD/F congener distributions of workers were differentiated from those of residents. But, all of them were similar to the distribution in several Korean foods. Estimated daily intake(EDI) of each person was calculated, and then only 40% to the total people were within the tolerable daily intake range(1-4pg I-TEQ/kg bw/day) suggested by WHO(1997).

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.20 no.1
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• pp.53-62
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• 2010

일샵 종사자들의 1) 공기 중 화학물질에 대한 노출정도를 파악하고 2) 공기 중 미량으로 존재하는 아세톤 및 톨루엔과 요 중 아세톤 및 마뇨산과의 연관성을 분석하여 후자들이 아직도 생물학적인 지표로 유용한지를 알아보고자 본 연구를 실시하였다. 경인 지역소재 9개의 네일숍에 근무하는 20명의 종사자들을 노출군으로 선정하였으며 이 작업과 무관한 일반 여성 20명을 대조군 선정하였다. 작업장 공기는 한 네일숍에 3개씩 총 27개의 시료를 가능한 한 작업자의 호흡영역에서 가장 가까운 곳에서 지역시료로 채취하였다. 공기 중 유기증기 13개 물질, 포름알데히드, 요 중 아세톤, 요 중 마뇨산을 가스크로마토그래프, 자외선분광광도계 그리고 GC/MS를 이용하여 분석하였다. 유기증기 13개 물질 중 아세톤과 톨루엔은 모든 네일샵에서 검출되었다. 각 네일샵 공기 중 유기증기의 노출정도를 기하평균(GM)과 복합물질간 상가작용을 이용하여 평가를 하였을 때 노동부 노출기준의 10%, ACGIH의 13% 수준에 불과하여 네일샵 종사자들의 유기증기에 대한 직업적인 노출정도는 매우 낮은 것으로 판단되었다. 요 중 아세톤과 마뇨산은 공기 중 아세톤과 툴루엔과 약한 상관성을 보였다(아세톤의 상관 계수 r=0.49, 톨루엔의 상관계수 r=0.45). 그러나 요 중 아세톤의 농도가 노출군과 대조군 간에 통계적으로 유의하지 않았으며 마뇨산은 대조군에 비해 노출군에서 약간 높은 것으로 나타났다. 따라서 저자들은 공기 중 아세톤과 톨루엔의 농도가 낮은 작업장에서 요 중 아세톤과 마뇨산을 생물학적 지표로 삼는 것은 적절하지 못한 것으로 결론지었다.

• Analytical Science and Technology
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• v.13 no.4
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• pp.520-533
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• 2000

We analyzed the PCDD/Fs and PCBs in human milk samples from a city and an industrial region by HRGC/HRMS. The average concentrations of PCDD/Fs and PCBs in human milk were 15.13 TEQ pg/g fat and 5.64 TEQ pg/g fat respectively. We discovered two kinds of homologue distributions. We compared congeners of each distributions with those of the commercial PCBs products. The daily intake of infant was predicted to be 60 TEQpg/kg/day according to the mean concentration of PCDD/Fs based on primipara. This value is much higher than the estimated range for background exposure to adult in the USA (1-3 TEQ pg/g fat).

• Analytical Science and Technology
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• v.13 no.1
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• pp.72-80
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• 2000

The HS/GC/MS method was performed to analyze the volatile organic compounds in waste sludge samples. This study was performed to establish the fundamental data by studying the effects of salt, equilibrium temperature and time in the volatile organic compounds analysis. The presence of salts have been found to increase the sensitivity. The peak area is increased from 1.07 to 2.61 times by adding the salts to the water sample, compared with a salt tree sample. The recoveries of target compounds have found between 90% and 127% at sample temperature of $85^{\circ}C$ for 30 min. This HS/GC/MS method can be applied to analyze the volatile organic compounds and organohalo compounds in the environmental matrix.

• Analytical Science and Technology
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• v.17 no.6
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• pp.443-453
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• 2004

Toluene is currently used as a major organic solvent of glues which are abused by the youngster for its hallucinogenic effect. In this study, toluene determination method using headspace gas chromatography (HS-GC) in the biological fluids like blood, urine and saliva of glue sniffers was validated and related uncertainties were estimated. LOD of $0.01{\mu}g/mL$ in saliva and LOQ of $0.1{\mu}g/mL$ in blood were the highest among LODs and LOQs in urine, blood and saliva. Other performance characteristics such as linearity, working range, accuracy, precision and recovery were also measured. The uncertainty at toluene concentration of $1{\mu}g/mL$ was estimated to be 0.13, 0.09 and $0.17{\mu}g/mL$ for blood, urine and saliva, respectively, and the uncertainty contribution from the least linear regression was dominant at the lower concentration of toluene.