• Safety and Health at Work
• /
• v.8 no.2
• /
• pp.220-225
• /
• 2017

Background: Benzene is a known occupational and environmental pollutant. Its urinary metabolite trans, trans-muconic acid (tt-MA) has been introduced by some environmental and occupational health regulatory associations as a biological index for the assessment of benzene exposure; however, recently, doubts have been raised about the specificity of tt-MA for low-level benzene exposures. In the present study, we investigated the association between urinary levels of tt-MA and inhalational exposure to benzene in different exposure groups. Methods: Benzene exposure was assessed by personal air sampling. Collected benzene on charcoal tube was extracted by carbon disulfide and determined by a gas chromatograph (gas chromatography with a flame ionization detector). Urinary tt-MA was extracted by a strong anion-exchange column and determined with high-performance liquid chromatography-UV. Results: Urinary levels of tt-MA in intensive benzene exposure groups (chemical workers and police officers) were significantly higher than other groups (urban and rural residents), but its levels in the last two groups with significant different exposure levels (mean = 0.081 ppm and 0.019 ppm, respectively) showed no significant difference (mean = $388{\mu}g/g$ creatinine and $282{\mu}g/g$, respectively; p < 0.05). Before work shift, urine samples of workers and police officers showed a high amount of tt-MA and its levels in rural residents' samples were not zero. Conclusion: Our results suggest that tt-MA may not be a reliable biomarker for monitoring low-level (below 0.5 ppm) benzene exposures.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.9 no.1
• /
• pp.173-186
• /
• 1999

To utilize diffuse sampling of formaldehyde in air, a new sampler was designed. A glass fiber filter was impegnated with 2,4-dinitrophenylhydrazine(DNP) and phosphoric acid and mounted 37mm cassette. The formaldehyde vapor was sampled in the dynamic chamber and measured by high performance liquid chromatograph and compared with solid sorbent tube. The results were as follows ; 1. The desorption efficiencies of diffusive sampler between 97.0% and 100%. 2. the sampling rate is constant as in $58{\sim}61.8m{\ell}/min$ when sampling times are between 120 and 360 min. 3. There was a significant relationship between concentrations of diffusive samples and active samples with the coefficient of determination(R2) of 0.92. 4. Desorbed amount of formaldehyde diffusive sampler was increased by high relative humidity. 5. Wheth diffusive samplers were stored at room temperature or at refrigerator there was no statistically significant difference in the accuracy of result. 6. When the diffusive samplers, which collected formaldehyde vapor, were exposed to clean air for three hours, there was no significant loss of formaldehyde due to reverse diffusion. In conclusion, this study suggest that developed diffusive samplers will be a reasonable substitute for the solid sorbent tube for sampling formaldehyde and practical comparative study of developed diffusive sampler should be performed at workplaces of manufacturing industry.

• YAKHAK HOEJI
• /
• v.48 no.6
• /
• pp.384-390
• /
• 2004

Polyphenol oxidase-catalyzed oxidation of substrates (t-butylcatechol, 4-methylcatechol, chlorogenic acid, caffeic acid and pyrocatechol) were performed in the Ph range 4~8. Co ncentrations of substrate's major oxidation products were monitored by high performance liquid chromatograph. The nature and amounts of products formed were highly pH dependent. They also were ifluenced by kinds of substrates. Major oxidation product of 4-methylcatechol appeared the maxium value at pH 5, them of chlorogenic acid, caffeic acid and pyrocatechol at pH 6.0 and that of t-butylcatechol at pH 5~7. Time-dependent PPO activity was determined at $4^{\circ}C\;and\;30^{\circ}C$. PPO extracted by phosphate buffer containing triton X-114 (t-PPO) was more stable than PPO by phosphate buffer (b-PPO). The result of electrophoresis, at first PPO was showed only a band at 48 kd. After 1~3 days a partial degrade band was appeared in b-PPO and three partial degrade bands in t-PPO. No activity band was appeared in PPOs at $30^{\circ}C$ and b-PPO at $4^{\circ}C$ after 4 days. And a band (37 kDa) in t-PPO was remained finally and disappered. PPO from Perillae leaves has two activity bands at 48 and 37 kDa in previous paper. It was supposed that PPO in the leaves of Perilla frutescens was a protein having one molecular weight as 48 kDa. And 37 kDa protein, relatively proteolysis-resistant, was a proteolyzed form of a major form.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.10 no.2
• /
• pp.165-172
• /
• 2000

This study was carried out to investigate relationship between plasma $\delta$ - aminolevulinic acid (ALAP) and lead exposure indices in exposure to lead. The subjects were 218 male workers in 2 storage battery companies and 2 secondary smelting companies. Blood lead(PbB), blood zinc-protoporphyrin( ZPP), urinary $\delta$ - aminolevulinic acid (ALAU), hemoglobin(Hb), and hematocrit(Hct) were measured as lead exposure indices. The results were as follows, 1. The means of blood lead and blood ZPP concentration of subjects were $27.2{\pm}14.0{\mu}g/d{\ell}$ and $55.1{\pm}47.6{\mu}g/d{\ell}$, respectively. The means of plasma $\delta$ - ALA and urinary $\delta$ - ALA concentration were $18.9{\pm}25.1{\mu}g/d{\ell}$ and $2.1{\pm}4.6mg/{\ell}$, respectively. 2. The concentration of ALAP was $11.2{\mu}g/{\ell}$ for below $20{\mu}g/d{\ell}$ PbB, $12.8{\mu}g/{\ell}$ for from $21-40{\mu}g/d{\ell}$ PbB, and $51.2{\mu}g/{\ell}$ for over $40{\mu}g/d{\ell}$ PbB, respectively. 3. ALAP was significantly correlated with ALAU(r=0.829, p<0.01), ZPP(r=0.724, p<0.01) and PbB(r=0.552, p<0.01).

• Proceedings of the Ginseng society Conference
• /
• 2002.10a
• /
• pp.238-252
• /
• 2002

In order to screen out indicators for the discrimination of ginseng habitat, some physical and chemical characteristics of Korean red ginsengs (94 kinds) and Chinese red ginsengs (50 kinds) were analyzed by using a rheometer, an electronic nose system, a combined technique of solid phase micro-extraction (SPME) and gas chromatograph equipped with an electron capture detector (GC/ECD), an X-ray fluorescence spectrometer (XRF), an inductively coupled plasma mass spectrometer (ICP/MS), a near infrared spectrometer (NIRs) and high performance liquid chromatography equipped with evaporative light scattering detector (HPLC/ELSD). The results are summarized as follows: (i) The rhizome strengths of Korean red ginsengs were significantly higher than those of Chinese red ginsengs. (ii) The electronic nose patterns of Korean red ginsengs were significantly different from those of Chinese red ginsengs. (iii) Some unidentified peaks were detected not in the headspace of Korean red ginsengs but in the headspace of Chinese red ginsengs when the headspace volatiles prepared by the SPME technique were analyzed by GC/ECD. (iv) Either the content ratios of K to Ca or Mn to Fe were significantly different between Korean red ginsengs and Chinese red ginsengs. (v) The reflectance ratios of NIRs wavenumbers such as $904\;cm^{-1}\;to\;1088\;cm^{-1}$ for Korean red ginsengs were significantly different from those for Chinese red ginsengs. (vi) The content ratios of ginsenoside-Rg to ginsenoside-Re of Korean red ginsengs were significantly higher than those of Chinese red ginsengs. These results indicate that the rhizome strength, the electronic nose pattern, the occurrence of ECD-sensitive headspace volatile components, the content ratios of K to Ca and Mn to Fe, the NIRs pattern and the content ratio of ginsenoside-Rg to -Re may be indicators for the discrimination of ginseng habitat.

• The Korea Journal of Herbology
• /
• v.33 no.5
• /
• pp.67-72
• /
• 2018

Objectives : Natural extracts have been extensively studied to replace single agent drugs that cause a variety of side effects. However, studies of changes to the formulation of natural extracts has not been nearly proceed. We aimed to investigate whether pharmacological stability of hyeonggaeyeongyotang gagambang (HYT) is altered by formulation changes for foaming tablet. Methods : In this study, we performed freeze - drying of HYT, which is known to have antioxidant and anti - inflammatory properties, and then changed the formulation by foaming. Results : As a result, the foaming reaction appeared normally when HYT foamed tablets were put into water, and almost all of the substances were dissolved in the aqueous solution. In addition, we confirmed using high-performance liquid chromatograph that the geniposide used as an indicator material of HYT was stable in most of the formulations. It was confirmed that the change of HYT formulation did not affect the antioxidant efficacy by the 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid assay. Moreover, quantitative real-time PCR confirmed that the inhibitory effect of HYT on IL-$1{\beta}$ mRNA expression induced by lipopolysaccharides treatment in murine macrophage RAW 264.7 cells was similar in the solution of foaming tablet. Conclusions : These results suggest that the materials with various pharmacological effects can be stably maintained even when the formulation is changed by the foaming action of HYT. Our results are expected to provide important basic knowledge on formulation changes using various natural extracts.

• Journal of Food Hygiene and Safety
• /
• v.29 no.3
• /
• pp.234-240
• /
• 2014

Fluxapyroxad is classified as carboxamide fungicide that inhibits succinate dehydrogenase in complex II of mitochondrial respiratory chain, which results in inhibition of mycelial growth within the fungus target species. This study was carried out to assure the safety of fluxapyroxad residues in agricultural products by developing an official analytical method. A new, reliable analytical method was developed and validated using High Performance liquid Chromatograph-UV/visible detector (HPLC-UVD) for the determination of fluxapyroxad residues. The fluxapyroxad residues in samples were extracted with acetonitrile, partitioned with dichloromethane, and then purified with silica solid phase extraction (SPE) cartridge. Correlation coefficient($R^2$) of fluxapyroxad standard solution was 0.9999. The method was validated using apple, pear, peanut, pepper, hulled rice, potato, and soybean spiked with fluxapyroxad at 0.05 and 0.5 mg/kg. Average recoveries were 80.6~114.0% with relative standard deviation less than 10%, and limit of detection (LOD) and limit of quantification (LOQ) were 0.01 and 0.05 mg/kg, respectively. All validation parameters were followed with Codex guideline (CAC/GL 40). LC-MS (Liquid Chromatograph-Mass Spectrometer) was also applied to confirm the analytical method. Base on these results, this method was found to be appropriate fluxapyroxad residue determination and can be used as the official method of analysis.

• Journal of Food Hygiene and Safety
• /
• v.31 no.3
• /
• pp.186-193
• /
• 2016

An analytical method was developed for the determination of oxathiapiprolin in agricultural commodities. Oxathiapiprolin is a new oomycide (fungicide of piperidinyl thiazole isoxazoline class) which controls downy mildew in cucurbits caused by Pseudoperonospora cubensis (oomycete plant pathogen). Agricultural commodities were extracted with acetonitrile and partitioned with dichloromethane to remove the interference, adjusting pH between 9 and 10 by 1 N sodium hydroxide. After purification by silica SPE cartridge to clean up the interference of organic compounds, they were finally quantified by HPLC-UVD (high performance liquid chromatograph ultraviolet detector) using a wavelength at 260 nm and confirmed by LC-MS (liquid chromatograph mass spectrometer) in electro-spray ionization positive ion mode. The standard calibration curve was linear with coefficients of determination ($r^2$) 1.00 over the calibration ranges (0.025-2.5 mg/L). Recoveries were ranged between 86.7 to 112.7%, with relative standard deviations less than 10% at three concentration levels (LOQ, 10LOQ, and 50LOQ) performing five replicates. The overall results were determined and estimated according to the CODEX guidelines (CAC/GL40). The proposed method for determination of oxathiapiprolin residues in agricultural commodities can be used as an official method.

• Journal of Korean Medicine Rehabilitation
• /
• v.21 no.2
• /
• pp.63-85
• /
• 2011

Objectives : This study was carried out to know the effects of Danggwisayeokgaohsuyusaenggang-tang(hereinafter referred to DST) on arthritis induced by collagen on DBA/1 OlaHsd mice. Methods : For this purpose, DST was orally administered to mouse with arthritis induced by collagen II. Cytotoxicity, high performance liquid chromatograph(HPLC) analysis, arthritis index, value of immunocyte in draining lymph node and paw joint, cytokine were measured in vivo. Results : 1. The cytotoxicity against human fibroblast cells(hFCs) was not measured in any concentration. 2. In HPLC analysis, There are high peak patterns at 8 minute(min), 12 min, 35 min, 45 min. 3. The arthritis index was decreased significantly. 4. The degree of arthritis induced damage of joint of DST group is slight compared with control group in histopathologic observation(Hematoxylin and eosin stain(H&E), Masson's trichrome(M-T) staining). 5. In total cell counts of draining lymph node(DLN) and paw joint, the cells in DLN decreased significantly on DST 200 mg/kg and the cells in paw joint decreased significantly on 200 mg/kg and 50 mg/kg. 6. In DLN, $CD4^+/CD25^+$, $CD3^+/CD69^+$, major histocompatibility complex(MHC), class-II/$CD11c^+$ cells decreased significantly on DST 200 mg/kg and 50 mg/kg $CD3^+/CD8^+$ cells decreased significantly on DST 200 200 mg/kg, $CD4^+$, $CD3^+/CD44^+$ cells decreased. 7. In paw joints, $CD4^+$, $CD11b^+/Gr-1^+$ cells decreased significantly on DST 200 mg/kg and 50 mg/kg. 8. In joints, levels of $IL-1{\beta}$, IL-6, $TNF-{\alpha}$, cyclo-oxygenase-2(COX-2), NOS-II were decreased on DST 200 mg/kg and DST 50 mg/kg. 9. In analysing of cytokine in CD3/CD28 activated spleen, IL-17 was decreased significantly, IL-4 was increased significantly $INF-{\gamma}$ was decreased on DST 200 mg/kg. 10. In analysing of cytokine in collagen activated spleen, IL-17 were decreased significantly, IL-4 was increased significantly. Conclusions : This results demonstrated that DST suppressed the inflammatory progression of collagen-induced arthritis(CIA) mice and supported further studies are required to survey continuously in looking for the effective substance and mechanism in the future.

• Journal of Environmental Health Sciences
• /
• v.38 no.2
• /
• pp.105-117
• /
• 2012

Objectives: This study aimed to assess the concentration of perfluorooctanoic acid (PFOA) and perfluorooctanesulfonate (PFOS) in blood and factors controlling their exposure among Koreans. Methods: Study subjects were selected to include 718 members of the general population residing in five metropolitan cities and the Gangwon Province area from August 2008 to January 2009. A questionnaire was administered to investigate lifestyle, socio-demographic characteristics, and other related factors. Blood samples were collected and extracted using solid-phase extraction and anion-exchange methods, and quantified by high-performance liquid chromatograph (HPLC, Agilent 1200 Series) coupled with a Triple Quad LC-MS/MS system (Agilent 6410). Results: Geometric mean concentrations of PFOA and PFOS in the blood were measured as 1.82 and 6.06 ng/ml, respectively. Mean PFOA and PFOS concentrations generally increased with age in both genders. Blood PFOA concentration was significantly different according to such variables as age, family income, residential district, and province. Blood PFOS concentration was significantly different by such variables as gender, age, lifestyle factors such as regular exercise, alcohol consumption, and smoking status. Also, family income, hazardous facilities, job classification, and province contributed significantly to differences in blood PFOS concentration levels. Conclusions: Blood PFOA and PFOS concentrations in Koreans were similar with those found in Japan, the USA, and Germany, but less than those in Australia. PFOA and PFOS exposure seems to be affected by a variety of factors in Korea. Therefore, investigation is required for each factor to assess the relative contribution of different variables.