• Journal of Engineering Education Research
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• v.7 no.2
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• pp.22-39
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• 2004

The study aims to explore whether the management and operation of national technique qualification system has a suitable role division between the government and non-government and to design plans for building it. To do so, a direction for role division between the government and non-government was investigated in the management, national technique qualification system. In addition, limitations in the operation of government-centered qualification system were pointed out by analyzing the present status on the management and operation of national technique qualification system and plans for role division between the government and non-government were proposed in the management and operation of qualification system. Various methods were applied to this study as its methodology: the collection and analysis of the relevant literatures, surveys targeting companies(internal qualification managers) and associations by industrial classification(owners' groups) as respondents, holding expert consultations for setting a direction in dividing roles between the government and non-government, interviews with companies and associations by industrial classification for gathering their opinions, forming and operating a collaborative research group consisting of specialists in qualification system.

• Analytical Science and Technology
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• v.32 no.6
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• pp.252-261
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• 2019

Pyrrolizidine alkaloids (PAs) are a group of secondary metabolites that are produced by plants all over the world as a defense mechanism against herbivores. To date, over 660 PAs have been identified from more than 6,000 plant species that have been reported to be widely present in plants belonging to Asteraceae, Boraginaceae, and Fabaceae. This study describes an analytical method based on UPLC-MS/MS for the quantitation of 7 pyrrolizidine alkaloids (Lycopsamine, Echimidine, Retrorsine, Retrorsine N-oxide, Senecionine, Heliotrine, and Trichodesmine) in honey, and was applied to 84 honey samples for validation. Quantitation was performed based on a matrix-matched calibration to compensate for the matrix effect on the electrospray ionization. Good linear calibrations were obtained for all 7 PAs in the spiked honey samples (2.575-202.14 ㎍/kg; R² ≥ 0.998). The extraction recoveries for most of the PAs in the honey samples were in the range of 81 %-108 %. The analysis showed that 6 of the 84 honey samples were contaminated by the PAs with the mean total sum of PAs being 47.19 ㎍/kg, and the concentrations of the PAs were observed to be in the range of 1.76-202.1 ㎍/kg. The retronecine type compounds (Echimidine, Lycopsamine) were the most frequently found PAs in honey. These data provide useful information for the assessment of human risk posed by the consumption of honey contaminated PAs.

• Journal of Environmental Impact Assessment
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• v.21 no.3
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• pp.353-365
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• 2012

This study is understanding characteristics and analyzing contributions of the odor causing compounds of complex-odor & major specified odor materials, and contribution analysis, caused pre-treatment facilities(input and storage) and post-treatment facilities(heating and drying). The target of this study is feeds-production-facilities, located in Seoul. The averaged complex-odor compounds on the boundary line is 21 times higher, and it is 15 times higher than emission standards. In cracking&collection(pre-treatment facilities), the concentration of compounds is 4,881 times, 2,080 times in drying, and 1,442 times in putting&storing facilities. Ammonia occupies the largest portion of the results of monitoring specified odor compounds in input&storage facilities, followed Acetaldehyde > Hydrogen sulfide > Methyl mercaptan. In cracking&collection, Ammonia also occupies most of odor compounds, followed Methyl mercaptan > Acetaldehyde > Dimethyl disulfide > Dimethyl sulfide > Hydrogen sulfide. Acetaldehyde > Methyl mercaptan in drying facilities. On the boundary line, however, the concentration of specified odor compounds stays below emission standards. The result of contribution analysis is that methyl mercaptan has the highest contribution in input & storage, as well as cracking&collection facilities, followed Acetaldehyde > Hydrogen sulfide > Dimethyl sulfide > Dimethyl disulfide. In the drying facilities, the contribution shows Methyl mercaptan > Acetaldehyde > i-Valeraldehyde and Butyraldehyde. Therefore, to decrease odor in foodwaste treatment facilities, proper prevention facilities need to be installed and operated, according to characteristics of individual odor compounds, based on monitored data.

• Journal of Food Hygiene and Safety
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• v.30 no.4
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• pp.366-371
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• 2015

This work was conducted to apply the multi class pesticide multiresidue method for determining the use of hexaconazole in the agricultural products using GC-NPD. The multi class pesticide multiresidue method results were validated for the assay of hexaconazole by using linearity, accuracy, precision, limit of detection and quantitation. The linearity in the concentration ranged from 0.025 to 5.0 mg/L ($R^2$ > 0.999). Lettuce recoveries ranged from 89.42% to 94.15% with relative standard deviations below 7.78%, for spiking levels from 0.04 to 4.0 mg/kg. The limit of detection was 0.04 mg/kg, and the limit of quantitation was 0.11 mg/kg. The intra- and inter-day precisions were 2.42~3.49% and 4.90~7.78%, respectively. We suggested that the multi class pesticide multiresidue method for determining hexaconazole was highly accurate and reproducible, and it will be used as a routine analysis in agricultural products.

• Journal of Environmental Health Sciences
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• v.39 no.2
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• pp.166-177
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• 2013

Objectives: The genus Legionella is common in aquatic environments. Some species of Legionella are recognized as potential opportunistic pathogens for human, notably Legionella pneumophila that causes, Legionellosis. Thus, we investigated the contamination of Legionella pneumophila on water supply systems in Seoul, including cooling towers, public baths, hospitals and fountains. Methods: The existence of 16S rRNA and mip gene of L. pneumophila was confirmed in the genome of the isolated strains by PCR. Results: During the summer season of 2010 and 2011, Legionella pneumophila were detected from 163 samples (21.1%) out of 772 samples collected. Among the 163 strains of L. pneumophila, eighty one isolates belonged to serogroup 1 (57.4%), 23 isolates were serogroup 5 (16.3%), 21 isolates were serogroup 6 (14.9%), 8 isolates were serogroup 2 (5.79%), and 8 isolates were identified in serogroup 3 (5.7%). Through PFGE (pulsed-field gel electrophoresis) analysis using Sfi I, genetic types of L. pneumophila were classified into five (A to E) patterns by the band similarity with excess of 70% from public baths. Conclusions: The PFGE patterns of the serotypes showed a tendency for diversity of L. pneumophila. Our results suggest the existence of serological and genetic diversity among the L. pneumophila isolates.

• Journal of Food Hygiene and Safety
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• v.31 no.1
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• pp.8-14
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• 2016

The purposes of this study are to confirm ways to reduce bacteria of minimally processed agricultural products, using antibacterial foods that are easily available in home and to improve bacterial hygienic condition of them. We chose garlic-allicin, ginger-gingerol, green tea-catechin, cinnamon-cinnamic aldehyde, wasabi-allyl isothiocyanate as antibacterial foods and their unique antibiotic materials. We confirmed the better washing effect when these antibiotic extracts were used, compared to washing effect by only distilled water. Their antibiosis was proved by statistical processing. PFGE (Pulsed Field Gel Electrophoresis) of Bacillus cereus shows continuous contamination probability of minimally processed vegetables by same product suppliers and the necessity of systematic measures against bacterial contamination.

• Journal of Food Hygiene and Safety
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• v.35 no.4
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• pp.354-364
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• 2020

For this paper we analyzed heavy metals including lead, cadmium, arsenic and mercury, and conducted risk assessment on 171 types of herbal medicines used as foods and drugs distributed in Seoul's Yangnyeongsi and Kyungdong (Gyeongdong) herbal medicine markets. The concentrations of the heavy metals were measured by the ICP-MS and a mercury analyzer. The detection ranges of the lead, cadmium, arsenic and mercury were found to be ND-4.719 mg/kg, ND-1.019 mg/kg, 0.002-8.696 mg/kg and ND-0.058 mg/kg, respectively. Artemisiae Capillaris Herba exceeded the standards of the MFDS (Ministry of Food and Drug Safety) for cadmium items, and Actinidiae Ramulus et Fulium et Fructus Vermicultus exceeded the standards for arsenic items. The non-carcinogenic risk assessment showed that there were no items exceeding 1 and that they were safe. The risk of carcinogenicity to lead was below 10^-6 in all items and was evaluated as safe. The risk of carcinogenicity of arsenic was almost all in the range of 10^-4 to 10^-6. All %PTWI are considered to be safe below 100.

• Journal of Environmental Health Sciences
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• v.47 no.5
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• pp.384-397
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• 2021

Background: With volatile organic compounds (VOCs) containing aromatic and halogenated hydrocarbons such as benzene, toluene, and xylene that can adversely affect the respiratory and cardiovascular systems when a certain concentration is reached, it is important to accurately evaluate the source and the corresponding health risk effects. Objectives: The purpose of this study is to provide scientific evidence for the city of Seoul's VOC reduction measures by confirming the risk of each VOC emission source. Methods: In 2020, 56 VOCs were measured and analyzed at one-hour intervals using an online flame ionization detector system (GC-FID) at two measuring stations in Seoul (Gangseo: GS, Bukhansan: BHS). The dominant emission source was identified using the Positive Matrix Factorization (PMF) model, and health risk assessment was performed on the main components of VOCs related to the emission source. Results: Gasoline vapor and vehicle combustion gas are the main sources of emissions in GS, a residential area in the city center, and the main sources are solvent usage and aged VOCs in BHS, a greenbelt area. The risk index ranged from 0.01 to 0.02, which is lower than the standard of 1 for both GS and BHS, and was an acceptable level of 5.71×10^-7 to 2.58×10^-6 for carcinogenic risk. Conclusions: In order to reduce the level of carcinogenic risk to an acceptable safe level, it is necessary to improve and reduce the emission sources of vehicle combustion and solvent usage, and eco-car policies are judged to contribute to the reduction of combustion gas as well as providing a response to climate change.

• Korean Journal of Food Science and Technology
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• v.53 no.3
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• pp.239-244
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• 2021

In the present study, liquid chromatography tandem-mass spectrometry was used to conduct a risk assessment of ethoxyquin and ethoxyquin dimer residues in 288 farmed fish sold in wholesale and traditional markets in Seoul. The detection range (detection rate) of ethoxyquin and ethoxyquin dimer was 0.005~0.309 mg/kg (4.9%) and 0.001~2.828 mg/kg (69.8%), respectively. Ethoxyquin was detected only in freshwater eels, loaches, catfish, and flatfish, whereas ethoxyquin dimer was present in all fish species. To estimate the dietary exposure levels of ethoxyquin and ethoxyquin dimer, the hazard index, calculated using the acceptable daily intake and estimated daily intake, ranged from 0.001 to 0.300%. Our results indicate that there is no significant exposure risk to humans from these farmed fish despite 10 farmed fish samples exceeding the maximum residue level (1.0 mg/kg as the sum of ethoxyquin and ethoxyquin dimer).

• Journal of the Society of Cosmetic Scientists of Korea
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• v.48 no.2
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• pp.147-155
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• 2022

From March to August 2021, a total of 66 lip makeup products were collected from Seoul to measure the contents of lead, arsenic, cadmium, antimony, and nickel, and compared by product type (lip gloss, lip balm and lip tint), production area (domestic and imported), and user (for adults and children). The average metal contents were as follows; 0.284 ㎍/g for lead, 0.020 ㎍/g for arsenic, 0.003 ㎍/g for cadmium, 0.004 ㎍/g for antimony and 0.415 ㎍/g for nickel. The results of lip cosmetics were below the recommended maximums in regulations on safety standards for cosmetics of Ministry of Food and Drug Safety.