• 한국산업보건학회지
• /
• 제26권2호
• /
• pp.178-187
• /
• 2016

Objectives: Diisocyanates are a potent inducer of diseases of the airways, especially asthma. In this study, toluenediamine(TDA) and methylenedianiline(MDA) in urine were evaluated as biomarkers of exposure to tolunenediisocyanate(TDI) and methylenediphenyl diisocyanate(MDI), respectively. Methods: Workers exposed to TDI and MDI, as well as non-occupationally exposed subjects, were studied and pre- and post-shift urine samples were collected from 8 control subjects and 8 workers from a factory which manufactures polyurethane products for reducing noise and vibration in automobiles. Airborne TDI and MDI(n=8) were sampled on solvent-free glass filters impregnated with n-butylamine and detected by liquid chromatography atmospheric pressure ionization tandem mass spectrometry. Urinary TDA and MDA were detected as pentafluoropropionic acid anhydride(PFPA) derivatives by liquid chromatography electrospray ionization tandem mass spectrometry. Results: The median levels of urinary 2,6-TDA(p<0.001), 2,4-TDA(p=0.001), and MDA(p<0.001) of workers in post-shift samples were significantly higher than those of controls. The median levels of urinary 2,6-0TDA($0.63{\mu}g/g$ creatinine vs $0.34{\mu}g/g$ creatinine, p=0.017) and MDA($4.21{\mu}g/g$ creatinine vs $3.18{\mu}g/g$ creatinine, p=0.017) of workers in post-shift samples were significantly higher than those of the pre-shift samples. There were significant correlations between the urinary 2,6-TDA, 2,4-TDA, and MDA of workers in post-shift samples and the airborne 2,6-TDI(rho=0.952, p<0.001), 2,4-TDI(rho=0.833, p=0.001), and MDI(rho=0.952, p<0.001). Conclusions: These urinary diamines, metabolites of diisocyanates, in post-shift samples were useful biomarkers to assess occupational exposure to diisocyanates.

• 실내환경 및 냄새 학회지
• /
• 제17권4호
• /
• pp.315-321
• /
• 2018

Phthalate is an endocrine disruptor that interferes with homeostasis and developmental regulation. It is highly toxic to the environment and is associated with various diseases of the human body. Using biological samples from 140 adult subjects, to evaluate the influencing factors which are related to contaminant concentration levels, we used correlation analysis and multiple regression analysis. Lastly, in order to analyze the health effects related to exposure to phthalates, we conducted a risk assessment by estimating acceptable daily intake exposure according to the influential factors. When we compared the concentration level according to influential factors, in general, the subjects who had engaged in home remodeling work had higher urinary phthalate metabolite concentrations levels than the subjects who had not engaged in home remodeling work. We can confirm statistically significant differences in DBP metabolites. In addition, we can confirm the concentration appeared higher in the categories such as using air freshener, sofa and foods. Through conducting a risk assessment of DEHP, BBzP, DiBP, and DnBP by using data on phthalate metabolite concentration in urine, it was found that the average concentration of all metabolites did not exceed TDI.

• Toxicological Research
• /
• 제34권3호
• /
• pp.199-210
• /
• 2018

Skeletal muscle can be ultrastructurally damaged by eccentric exercise, and the damage causes metabolic disruption in muscle. This study aimed to determine changes in the metabolomic patterns in urine and metabolomic markers in muscle damage after eccentric exercise. Five men and 6 women aged 19~23 years performed 30 min of the bench step exercise at 70 steps per min at a determined step height of 110% of the lower leg length, and stepping frequency at 15 cycles per min. $^1H$ NMR spectral analysis was performed in urine collected from all participants before and after eccentric exercise-induced muscle damage conventionally determined using a visual analogue scale (VAS) and maximal voluntary contraction (MVC). Urinary metabolic profiles were built by multivariate analysis of principal component analysis (PCA) and orthogonal partial least square-discriminant analysis (OPLS-DA) using SIMCA-P. From the OPLS-DA, men and women were separated 2 hr after the eccentric exercise and the separated patterns were maintained or clarified until 96 hr after the eccentric exercise. Subsequently, urinary metabolic profiles showed distinct trajectory patterns between men and women. Finally, we found increased urinary metabolites (men: alanine, asparagine, citrate, creatine phosphate, ethanol, formate, glucose, glycine, histidine, and lactate; women: adenine) after the eccentric exercise. These results could contribute to understanding metabolic responses following eccentric exercise-induced muscle damage in humans.

• 분석과학
• /
• 제13권1호
• /
• pp.121-126
• /
• 2000

이 연구의 목적은, 톨루엔에 노출된 근로자의 생물학적모니터링에 있어 혼재하는 유기산의 종류와 분석방법에 따른 요중 마뇨산 분석값을 비교하여, 다른 유기산이 혼재할 경우 UV법으로 분석했을 때 일어날수 있는 방해효과를 측정하는데 있다. 마뇨산만 포함된 소변 표준시료와 마뇨산, 메틸마뇨산, 페닐글리옥실산, 만델산 등 각각 다른 유기용제의 대사물이 포함된 소변 표준시료를 UV법, HPLC법으로 분석하고 유기산의 방해효과(IE; Inteference Efect)를 계산하였다. 또한 이들 소변 표준시료에 대해 전국 100개 검진기관을 대상으로 한 외부정도관리 결과, 참가기관들이 사용한 분석방법에 따른 요중 마뇨산 분석값을 비교하였다. 톨루엔과 크실렌에 노출된 근로자의 소변을 UV법으로 분석할 경우 크실렌 대사물인 메틸마뇨산은 마뇨산 분석값에 영향을 주어, 마뇨산 농도 0.33 g/L에서 0.5-2.0 g/L의 농도로 공존시 60-82%의 방해 영향을 가진 것으로 나타났다. 그러나 스티렌 대사물인 만델산, 페닐글리옥실산은 마뇨산 분석값에 거의 영향이 없었다. 따라서 톨루엔과 크실렌이 함께 노출되는 경우 소변 모니터링시 UV법을 사용하는 것보다 GC법이나 HPLC법을 사용하는 것이 바람직하다. 특히 특수검진기관의 의무 보유장비인 GC법은 경제적이고 신속하며 정확도가 높은 방법으로 UV법에 대체하여 사용할 수 있는 것으로 나타났다.

• 한국산업보건학회지
• /
• 제6권1호
• /
• pp.28-37
• /
• 1996

Benzidine, an aromatic amine used primarily in the manufacture of azo dyes, is recognized as a urinary bladder carcinogen in humans. In rats, mice, and hamsters, chronic exposure to benzidine resulted in tumors of the liver. The present study was undertaken to suggest analyzing the metabolites of benzidine with the optimal condition, identify the metabolites of benzidine, and observe time variance of the metabolites in the isolated perfusated rat liver. N-acetylbenzidine was synthesized by acetylation of benzidine with acetic anhydride and separated by thin layer chromatography(TLC) and high performance liquid chromatography(HPLC). To analysis benzidine and the metabolites of benzidine, HPLC operating condition has been optimized by means of preliminary experiment. The mobile phase consisted of acetonitrile(37%) in phosphate buffer, flow rate maintained at 1.0 ml/min. Optimal detective conditions were electrochemicaldetector(ECD) at 0.75 V for benzidine and N-acetylbenzidine and ultravioletdetector(UVD) at 287 nm for N,N'-diacetylbenzidine. The separation system was composed of a guard column and a separation column(Polymer C18, $4.6{\times}250cm$) at a temparature of $40^{\circ}C$. The perfusion system was equilibrated for 30 minutes before addition of benzidine to the perfusate. Samples of the perfusate were collected at time intervals(0, 10, 20, 30, 60, 90, 120 min) during the 2 hour perfusion. Before analyzing samples by HPLC/ECD/UVD, samples had been treated with sep-pak. Samples of perfusate analyzed by HPLC/ECD/UVD and the metabolites of benzidine in the isolated perfused rat liver were N-acetylbenzidine and N,N'-diacetylbenzidine. Benzidine metabolized over 60% during the initial 30 minutes of perfusion, extensively by 1 hour, and was undetectable in the perfusate. N-acetylbenzidine increased by 30 minutes of perfusion, declined. N,N'-diacetylbenzidine increased the 0-90 minutes period, remained constant during the 90-120 minutes period.

• 한국환경보건학회지
• /
• 제48권6호
• /
• pp.315-323
• /
• 2022

Background: Socioeconomical disadvantaged communities are more vulnerable to environmental chemical exposure and associated health effects. However, there is limited information on chemical exposure among vulnerable populations in Korea. Objectives: This study investigated chemical exposure among underprivileged populations. We measured urinary metabolites of phthalates in urban disadvantaged communities and investigated their correlations with residential environment factors and relative socioeconomic vulnerability. Methods: Urine samples were collected from 64 residents in a disadvantaged community in Seoul. A total of eight phthalate metabolites were analyzed by liquid chromatography-mass spectroscopy. Analytical method used by the Korean National Environmental Health Survey (KoNEHS) was employed. Covariate variance analysis and general linear regression adjusted with age, sex and smoking were performed. Results: Several phthalate metabolites, namely monomethyl phthalate (MMP), monoethyl phthalate (MEP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), and mono-n-butyl phthalate (MnBP) had higher levels than those reported in the adults of 4th KoNEHS. Notably, the MnBP level was higher in the lower socioeconomic group (geometric mean [GM]=47.3 ㎍/g creatinine) compared to non-recipients (GM=31.9 ㎍/g creatinine) and the national reference level (GM=22.0, 28.2 and 32.2 ㎍/g creatinine for adults, 60's and 70's, respectively.). When age, sex and smoking were adjusted, MEP and MnBP were significantly increased the lower socioeconomic group than non-recipients (p=0.014, p=0.023). The lower socioeconomic group's age of flooring were higher than non-recipients, not statistically significant. Conclusions: These results suggest that a relatively low income and aged flooring could be considered as risk factors for increased levels of phthalate metabolites in socioeconomic vulnerable populations.

• 한국산업보건학회지
• /
• 제25권4호
• /
• pp.493-505
• /
• 2015

Objectives: The purpose of this study was to evaluate the relevance of adjusting a urinary sample for urine hippuric correction value and its effects. Urinary biological monitoring data are typically adjusted to a constant creatinine and specific gravity concentration to correct for variable dilutions among spot samples. This study was conducted to evaluate the suitability of adjusting the urinary concentrations of urine creatinine and specific gravity(SG). Methods: We measured the concentrations of hippuric acid, in spot urine samples collected from control(119), case(120) individuals. The value of hippuric acid was adjusted by SG and urinary creatinine(HPLC & Jaffe). Results: The major results were as follows. The concentrations of urinary creatinine and SG for the control group were 1.84 g/L(SD 0.99) for arithmetic mean and 1.56 g/L(GSD 1.86) for geometric mean by HPLC method, 1.57 g/L (SD, 0.82) for arithmetic mean and 1.33 g/L(GSD 1.85) for geometric mean by Jaffe method, 1.028(SD 0.09) for arithmetic mean and 1.02(GSD 1.06) for geometric mean by refractometer. Hippuric acid levels were 0.40 g/L(SD 0.51) by arithmetic mean and 0.20 g/L(GSD 3.59). In that case the exposed group was 1.40 g/L(SD 0.58) for arithmetic mean and 1.28 g/L(GSD 1.55) for geometric mean by HPLC method, 1.27 g/L(SD 0.56) for arithmetic mean and 1.14 g/L(GSD 1.62) for geometric mean by Jaffe method, 1.045 L(SD 0.27) for arithmetic mean and 1.02(GSD 1.13) for geometric mean by refractometer(P<0.05). Hippuric acid levels were 0.67 g/L(SD 0.79) for arithmetic mean and 0.39 g/L(GSD 2.94)(p<0.05). The urine creatinine concentrations were affected by gender(p < 0.01) but SG levels were not affected by gender or age(p>0.05). After adjustment, urine hippuric acid was correlated with creatinine(HPLC & Jaffe)(r=0.723, P<0.05, r=0.708, P<0.05) and SG(r=0.936, P<0.05) and the control group shows significantly higher than the case group. In the case group for adjusted urine hippuric acid was correlated with creatinine(HPLC & Jaffe), (r=0.736, P<0.05), r=0.549, P<0.05), SG(r=0.549, P<0.05). After adjusting urine hippuric acid by urine creatinine(HPLC and Jaffe method) and specific gravity, significant associations were found between the control group and case group, respectively(r=0.832, P<0.05, r=0.845, P<0.05) and (r=0.841, P<0.05, r=0.849, P<0.05). Specific gravity adjustment appears to be more appropriate for variations in the urine creatinine method. Conclusion: we found that urinary creatinine concentrations were significantly affected by gender, and other factors and that care should therefore be exercised when correcting urinary metabolites according to the urinary creatinine concentration in spot urine. It is determined that additional study is needed for biological monitoring.

• 대한예방의학회:학술대회논문집
• /
• 대한예방의학회 1999년도 제51차 추계 학술대회 연제집
• /
• pp.94-95
• /
• 1999

• 한국환경과학회지
• /
• 제9권3호
• /
• pp.209-214
• /
• 2000

The preventive effects of sodium molybdate on the acute toxicity of lead were studied by investigating tissue accumulation of lead, changes of nerve conduction velocity and concentrations of metabolites related to function of sciatic nerve in rats treated with lead, sodium molybdate and both, respectively. In lead-intoxicated rat, the conduction velocity, myo-inositol concentration and $Na^{+}/K^{+}$ ATPase activity of sciatic nerve were decreased by about 33 %, 48 % and 58 %, respectively. However, sodium molybdate treatment significantly normalized the conduction velocity, $Na^{+}/K^{+}$ ATPase activity and myo-inositol concentration of sciatic nerve in lead-intoxicated rat. Also, sodium molybdate treatment decreased the contents of lead in blood and sciatic nerve through promotion of urinary excretion of lead. But sodium molybdate treatment did not affect the glucose concentration in sciatic nerve. These results suggest that sodium molybdate prevented peripheral neuropathy not only by reducing lead contents in sciatic nerve and blood, but also by enhancing $Na^{+}/K^{+}$ ATPase activity in sciatic nerve.

• 대한예방의학회:학술대회논문집
• /
• 대한예방의학회 1996년도 제48차 추계 학술대회 연제집
• /
• pp.205-206
• /
• 1996