• 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.

• Environmental Analysis Health and Toxicology
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• v.17 no.2
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• pp.147-160
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• 2002

Volatile organic compounds (VOCs) are an important public health issue in Korea and many important questions remain to be addressed with respect to assessing exposure to these compounds. Because they are ubiquitous and highly volatile, special techniques must be applied in their analytic determination Valid Personal exposure assessment methods are needed to evaluate exposure frequency, duration and intensity, as well as their relationship to personal exposure characteristics. Biological monitoring is also important since it may contribute significantly in risk assessment by allowing the estimation of effective absorbed doses. This study was on ducted to establish the environmental measurement, personal dosimetry and biological monitoring methods for VOCs. These methods are needed to compare blood, urinary and exhalation breath VOC levels and to provide tools for risk assessment of VOC exposure. Passive monitors (badge type) and a active samplers (trap) for the VOCs collection were used for air sampling. Methods development included determining the minimum detectable amounts of VOCs in each media, as well as evaluating collection methods and developing analytical procedures. Method reliability was assessed by determining breakthrough volumes and comparing results between laboratories and with other methods. A total capacity of trap used in this study was 60ι. Although variable by compound, the average breakthrough was 20％. Also, there was no loss of compounds in trap even if keep for 45 day in -7$0^{\circ}C$. The recovery of active and passive methods was 69％ ~ 126％ and method detection limit was 0.24 $\mu\textrm{g}$/trap and 0.07 $\mu\textrm{g}$/badge. There was no statistical difference (P > 0.05) between active and passive methods.

• Environmental Analysis Health and Toxicology
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• v.19 no.2
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• pp.217-225
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• 2004

In order to evaluate a health effect of air pollution, we designed exposure group (taxi driver, street sweeper, street trader,) and non -exposure group (office clerk). We analysed exposure and biologic marker by using personal sampler. Mean NO$_2$ and benzene level in each group were statistically significant. Also, respiratory symptom, chronic cough, sputum, and dyspnea on exertion were statistically significant in each group.

• Journal of Korean Society for Atmospheric Environment
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• v.2 no.1
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• pp.55-72
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• 1986

This study was made to determine the factors involving personal exposure levels of nitrogen dioxide for housewives living in urban area in two seasons, winter and summer. Nitrogen dioxide was measured with a small passive sampler containing triethanolamine. The samplers were set for 24 hours at three points. They were places: on the collar of the housewife to investigate the personal exposure level, near the TV in the living room (indoor level), and near the porch of their house (outdoor level). The subjects recorded the times of cooking using a gas range, using a kitchen ventilator, passive smoking, kerosene heater, total number of minutes at an open window, going out of home, etc.$\ldots. There was an apparent increase in personal exposure level in the case of the unvented heater and also an increase by cooking on a gas range. There was no marked increase in the other situations. There was an increase in the indoor level by cooking on a gas range, only in western style cooking in the winter season. Through these observations, we concluded that personal exposure level of nitrogen dioxide was strongly related to indoor nitrogen dioxide level, and factors involving indoor nitrogen dioxide level seemed different between winter and summer. The most significant difference in nitrogen dioxide level was indoor pollution in the winter and the outdoor environment in the summer. The maximum personal exposure level appeared in the western and tenement house in the winter and the traditional korean house in the summer.

• 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.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.22 no.3
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• pp.217-223
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• 2012

Objectives: This study was conducted to evaluate personal and area exposure of airborne nicotine during harvest and weaving tasks in tobacco farms. Methods: Nicotine was measured with NIOSH method 2551 and Passive sampler which was validated in previous papers for area and personal sampling. Results: The average (geometric mean) concentrations of nicotine with two different tasks in personal sample were 6.5 ${\mu}g/m^3$ (harvest), 32.6 ${\mu}g/m^3$ (weaving) and in area sample were 0.8 ${\mu}g/m^3$ (harvest), 57.2 ${\mu}g/m^3$ (weaving). There was significant difference in area sample between harvest and weaving task (p=0.000). Also, there was significant difference with personal sample (p=0.000). Conclusions: It was found that weaving task should be considered to be the first priority for reducing nicotine exposure.

• Journal of Environmental Health Sciences
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• v.27 no.1
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• pp.20-26
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• 2001

personal nitrogen dioxide(NO$_2$) exposures for 31 professional drivers were measured using passive sampler and time activity diary in Asan and Chunan area, and were estimated using time-weighted average model. Mean concentrations of driver’s indoor and outdoor were 24.7$\pm$10.7 ppb and 23.3$\pm$8.3 ppb, respectively with indoor/outdoor of 1.1. Mean personal NO$_2$ exposure was 30.3$\pm$9.7 ppb. Personal NO$_2$ exposures were strongly correlated with indoor car NO$_2$ levels ($R^2$=0.80) rather than residential indoor NO$_2$ level ($R^2$=0.55). and outdoor NO$_2$ level ($R^2$=0.50). The driver’s NO$_2$ exposure using LP-gas with 24.4$\pm$8.0 ppb were statistically different from those using diesel with 36.3$\pm$14.1 ppb(p<0.01). The effect of driver’s smoking for personal NO$_2$ exposure was not found. It was considered that the main NO$_2$in driver is transportation. Since drivers mostly spent their times in indoor and inside car, time-weighted average model could be used to estimated personal NO$_2$ exposure using time activity diary, Though we did not measure all microenvironments, the estimated personal NO$_2$ exposures with 26.9$\pm$10.2 ppb were statistically correlated with measured personal NO $_2$ exposures30.3$\pm$9.7 ppb ($R^2$=0.89). The mean and standard deviation of personal NO$_2$ exposure using Mote-Carlo simulation were 26.6$\pm$7.2 ppb.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.11 no.1
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• pp.34-41
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• 2001

Passive samplers have been used for personal, indoor, and outdoor air monitoring of VOCs at ppb concentrations in community and office environments. The path length of modified passive sampler was shortened, so it was intended to increase an uptake rate. The performance of the modified 3M 3500 organic vapor monitor(OVM) as a tool for assessing exposures to toxic air pollutants in nonoccupational community environments was evaluated using combined controlled test atmospheres of six selected target volatile organic compounds(VOCs): benzene, methyl tert-butyl ether(MTBE), chloroform, 1,4-dichlorobenzene, tetrachloroethylene, and toluene. The experiments were conducted by exposing the dosimeters to concentrations of $50{\sim}100{\mu}g/m^3$ on six face velocity(0.00, 0.02, 0.06, 0.12, 0.20, 0.30 m/sec) for 24 hours. If the uptake rate was increased, that means that we could use the passive sampler more effectively. The uptake rates were increased linearly according to reduce the path length. Although the diffusion path length was shortened, the change of uptake rate was within ${\pm}25%$ of theoretical value, indicating that the modified passive sampler(TM) can be effectively used over the range of concentrations and environmental conditions tested with a 24-h sampling period if the face velocities were over 0.12 m/s for 6 components of VOCs. But when the face velocities were less than 0.12 m/s, uptake rates were reduced more than expected values. So, the passive sampler with the shortened path length should be used at indoor or outdoor environment where the face velocity should be over about 0.10 m/s. If the path length was shortened more, the uptake rate was more effected by starvation.

• Journal of Environmental Health Sciences
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• v.37 no.5
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• pp.369-375
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• 2011

Objectives: Exposure to hazardous chemicals during pregnancy may result incritical reproductive health outcomes. Indoor residential levels are significant component of personal exposure. The collection of residential exposure data has been hampered by the cost and participant burden of health studies of indoor air pollution. This study utilized a participant-based approach to collect volatile organic compounds concentration from homes. Methods: Four hundred thirteen women were recruited from three major hospitals in Seoul and Gyeongi Provence and 411 agreed to participate. A passive sampler (OVM 3500, 3M, USA) with instructions were given to the participants, as well as a questionnaire. They were asked to deploy the sampler in their homes for three to five days and return them viapre-stamped envelope. Results: Three hundred forty six participants returned the sampler. Among the returned samplers, three hundred samplers satisfied our monitoring quality criteria. The success rate of the monitoring method was 73%. The geometric mean of TVOC level was 429(2) ${\mu}g/m^3$. The TVOC guideline of 500 ${\mu}g/m^3$ was exceeded in 38% of the houses. The residential VOC levels were significantly associated with remodeling of the house. Conclusions: The results suggested that a participant-based sampling approach may be a feasible and costeffective alternative to exposure assessment involving home visits by a field technician.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.1 no.1
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• pp.68-72
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• 1991

The present investigation studied the welding fumes produced during the arc welding process at a shipyard. The air at the shipyard was sampled (between February and May, 1990) to determine the total welding fume concentration, its heavy metal content and the concentrations of different sized particles of the welding fumes. The results were as follows : 1. Forty-four out of 50 samples showed welding fume concentrations which exceeding the threshold limit value of $5mg/m^3$. The geometric mean of welding fume concentration was $9.73mg/m^3$ ($2.14-24.86mg/m^3$), and the nighest level was found at the dock assembly shop ($12.0mg/m^3$). 2. The welding fume concentration measured with personal air sampler was 4.2 times greater than that measured with area sampler. 3. Of the heavy metals analyzed, Fe was found to be the most concentrated at $1.29mg/m^3$ ; it constitued 13.3% of the total welding fume concentration. 4. Of the different sized particles that make up the welding fumes, there was a tendency for the smaller particles to be more concentrated. Particles that measured $7{\mu}$ or less in diameter constituted 85.8% of the total welding fume concentration.