• 분석과학
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• 제15권3호
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• pp.196-213
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• 2002

물 시료 중 알킬페놀류, 클로로페놀류 및 비스페놀 A의 동시분석을 기체크로마토그래피/질량분석기-선택이온검색법을 사용하여, US EPA 분석방법, isoBOC 유도체화 분석방법과 TBDMS 유도체화 분석방법을 비교하였다. 시료의 전처리는 유기용매로 추출하고 농축하여 분석한 방법과 XAD-4를 이용한 액체-고체 추출 후 isoBOC 유도체화와 TBDMS 유도체화를 실시하였다. 11종의 페놀류에 대한 회수율 실험은 3차 증류수에 각각 10 ${\mu}g/{\ell}$ (US EPA 방법) 또는 2 ${\mu}g/{\ell}$ (isoBOC 유도체화 분석방법과 TBDMS 유도체화 분석방법)의 농도를 대상으로 측정한 결과 각각 85.1~109.9%와 90.3~126.6%의 결과를 얻었다. 각 분석방법의 비스페놀 A에 대한 분석방법 검출한계는 US EPA 분석방법, isoBOC 유도체화 분석방법과 TBDMS 유도체화 분석방법이 각각 0.732 ${\mu}g/{\ell}$, 0.002 ${\mu}g/{\ell}$와 0.021 ${\mu}g/{\ell}$로 나타났으며, $5{\sim}400ng/{\ell}$의 농도 범위에서 isoBOC 유도체화 분석방법과 TBDMS 유도체화 분석방법 각각 0.9755~0.9981과 0.9908~0.9996의 직선성을 보였다. 폴리에틸렌 공장의 방류수를 대상으로 잔류량을 측정한 결과 일부페놀이 검출한계 이하에서 흔적으로 나타났다.

• Toxicological Research
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• 제21권2호
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• pp.167-173
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• 2005

Bisphenol A (BPA) is a monomer used in the manufacture of a multitude of chemical products, including epoxy resins and polycarbonate. The objective of this study was to evaluate the effects of BPA administration on reproductive characteristics and blood hematological and chemical values in offspring of pregnant dams treated with BPA. BPA was administrated to pregnant mice by intraperitoneally injection with 0, 0.05, 0.5 and 5.0 mg/kg B.W. for 5 times at 3 days interval on gestation days 1-16. There were no treatment-related effects of BPA on reproductive organ weight in male offsprings at 45 days-of-age, but body weight was the lowest in 5.0mg BPA group when compared to other groups (P<0.05). No differences in semen characteristics (sperm concentration, viability, motility and abnormality) were observed between the control and BPA treatment groups. The WBC, HB, HT, MCV, MCH, MCHC, albumin, BUN and total protein of blood hematological and chemical values in male offsprings were not difference for any treatment groups, but RBC value in BPA groups was significantly increased comparing to the control group (P<0.05). The PLT value was slightly higher in 5.0mg BPA groups than in any other group, but not significantly difference among the experimental groups. In female offsprings, the effects of BPA didn't affect to the body and ovary weight, but the uterus weight in 5.0mg BPA group was slightly heavier than that of control group (P>0.05). No statically significant difference in blood hematological values in female offsprings were observed between the control group and BPA groups, but the concentration of albumin and BUN were significantly higher in 0.5mg BPA group when compared to control and other BPA treatment groups (P<0.05). The histological evaluation of testis and ovary in growing offspring at 45 days-of-age was not difference between the control group and BPA groups, but endometriosis of the uterus in female offspring was dramatically increased in 0.5 and 5.0mg BPA groups. These founding suggest that low concentration of BPA might not have a important role on reproductive ability or blood metabolite in offspring of pregnant dams treated with BPA.

• 대한화학회지
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• 제47권5호
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• pp.472-478
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• 2003

본 연구에서는 표면처리된 제올라이트에 따른 제올라이트/DGEBA의 경화 동력학과 기계적 계면특성을 고찰하였다. 경화제는 4, 4''-diamino diphenyl methane(DDM)을 사용하였으며, 제올라이트는(PZ) 15와 35 wt% KOH (15-BZ 그리고 35-BZ)로 표면처리하여 XPS와 XRD로 분석하였다. 경화 동력학은 DSC로 분석하였으며, 시편의 기계적 계면특성은 임계응력 세기인자(critical stress intensity factor, $K_{IC}$)와 임계변형에너지 방출속도(critical strain energy release rate, GIC)를 통하여 알아보았다. XPS와 XRD의 결과로부터, KOH로 표면처리된 제올라이트는 나트륨 (Na)이 칼륨(K)으로 이온교환되었으며, 표면처리로 인한 Al-O의 결합세기의 약화로 $Si_{2p}/Al{2p}$의 값이 증가하였다. 동적 DSC와 기계적 계면특성 결과로부터, 제올라이트/DGEBA 중에서 15-BZ의 경화 활성화에너지($E_a$)는 감소하였으며, $K_{IC}$와 $G_{IC}$는 증가하였다. 이러한 결과들은 제올라이트의 표면처리에 의해 산성도가 증가하였으며, 이렇게 증가된 산성도가 제올라이트와 에폭시 사이의 경화반응에 영향을 준 것으로 관찰된다.

• 환경생물
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• 제34권1호
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• pp.48-55
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• 2016

본 연구는 자외선 광분해에 의한 비스페놀 A (BPA)의 에스트로겐 활성 저감에 미치는 하수처리장 방류수 유기물질의 영향을 조사하였다. 방류수 유기물질과 표준으로 사용한 스와니강 자연 유기물질은 극성에 따라 소수성, 반친수성, 친수성 분획으로 분리하였다. 특이 자외선 흡수 (SUVA) 분석 결과, 방류수 유기물질은 높는 소수성을 가지고 있는 자연 유기물질과 다르게 소수성이 낮은 미생물 기원 유기물질과 유사한 특성을 나타내었다. 3시간의 자외선 조사는 방류수 및 자연 유기물질의 극성에 따라 SUVA 값을 유의하게 감소시켰다 (p<0.0001). 유기물질이 없는 조건에서, BPA($5.0{\times}10^{-5}M$)의 상대 에스트로겐 활성도는 자외선 광분해에 의해 86%에서 63%로 감소하였다. 그러나 유기물질이 있는 조건에서 상대 에스트로겐 활성도는 평균적으로 68%에서 37%로 감소하였으며, 유기물질의 종류 (방류수 또는 자연유기물질) 및 극성 (소수성, 반친수성, 친수성)과 유의한 차이를 나타내지 않았다 (p>0.05). 결과적으로, 유기물질이 있고 없는 조건에서 자외선 광분해에 의해 감소한 BPA의 상대 에스트로겐 활성도는 각각 31%와 23%였으며, 이것은 방류수와 자연 유기물질 모두 광분해에 의한 BPA의 에스트로겐 활성 저감을 촉진시킨다는 것을 제시한다.

• Toxicological Research
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• 제21권1호
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• pp.31-37
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• 2005

The inhibitory activity against bisphenol-A (BPA), one of well-known endocrine disrupters was examined with the water extracts prepared from the Stem Bark of Syringa velutina (SBS). In this study, we have investigated the effect of SBS on the toxicity caused by BPA in human breast cancer cell line, MCF-7 cells and immature Sprague-Dawley rats. In the estrogen receptor-mediated proliferation assay using MCF-7 cells, BPA (16 ng/ml) induced the cell proliferation, but the water extract of SBS inhibited BPA-induced cell proliferation in a dose-dependent manner. These results are associated with PARP degradation and specific cleavage of anti-apoptotic protein Bcl-2 of apoptotic regulatory factors. Additionally, the BPA (400 mg/100 g) significantly induced the increase of the uterine and virginal weights, while SBS (50 mg/100 g) showed the inhibitory action against BPA, i.e. caused the increase of estrogen-related organ weights in immature rat uterotrophic assay. Taken together, the present data suggest that SBS may have anti-toxicity activities against BPA in vitro and in vivo systems. SBS may be capable of inhibiting adverse effects of BPA such as reproductive disorder.

• Molecular & Cellular Toxicology
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• 제4권4호
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• pp.348-354
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• 2008

Bisphenol A (BPA), an environmental endocrine disrupter, enters the human body continuously in food and drink. Young children are likely to be more vulnerable than adults to chemical exposure due to the immaturities of their organ systems, rapid physical development, and higher ventilation, metabolic rates, and activity levels. The direct effect of BPA on peripheral tissue might also be of importance to the development of insulin resistance. However, the influence that BPA has on insulin signaling molecules in skeletal muscle has not been previously investigated. In this study, we examined the effect of BPA on fasting blood glucose (FBG) in post-weaned Wistar rats and on insulin signaling proteins in C2C12 skeletal muscle cells. Subsequently, we investigated the effects of BPA on insulin-mediated Akt phosphorylation in C2C12 myotubes. In rats, BPA treatment (0.1-1,000 ng/mL for 24 hours) resulted in the increase of FBG and plasma insulin levels, and reduced insulin-mediated Akt phosphorylation. Furthermore, the mRNA expression of insulin receptor (IR) was decreased after 24 hours of BPA treatment in C2C12 cells in a dose-dependent manner, whereas the mRNA levels of other insulin signaling proteins, including insulin receptor substrate-1 (IRS-1) and 5'-AMP-dependent protein kinase (AMPK), were unaffected. Treatment with BPA increased GLUT4 expression and protein tyrosine phosphatase 1B (PTP1B) activity in C2C12 myotubes, but not in protein levels. We conclude that exposure to BPA can induce insulin resistance by decreasing IR gene expression, which is followed by a decrease in insulin- mediated Akt activation and increased PTP1B activity.

• Journal of Preventive Medicine and Public Health
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• 제40권2호
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• pp.155-161
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• 2007

Objectives : Bisphenol A diglycidyl ether (BADGE) is the major component in commercial liquid epoxy resins, which are manufactured by co-reacting bisphenol A with epichlorohydrin. This study was performed to show the developmental effects of prenatal and postnatal exposures to BADGE in male rat offspring. Methods : Mated female rats were divided into four groups, each containing 12 rats. The dosing solutions were prepared by thoroughly mixing BADGE in corn oil at the 0, 375, 1500 and 3000 mg/kg/day concentrations. Mated females were dosed once daily by oral gavage on gestation day (GD) 6 - 20 and postnatal day (PND) 0 - 21. Pregnant female dams were observed general symptoms and body weight. Also, male pups were observed the general symptoms, body weight, developmental parameters (e.g. anogenital distance, pina detachment, incisor eruption, nipple retention, eye opening, testis descent), organ pathologic changes and hormone levels of plasma. Results : Pregnant rats treated with BADGE died at a rate of about 70% in the 1500 mg/kg/day group and all rats treated with 3000 mg/kg/day died. Body weight, for male pups treated with doses of 375 mg/kg/day, was significantly lower than in the control group at PND 42, 56, and 63 (p<0.05). Evaluation of body characteristics including; separation of auricle, eruption of incisor, separation of eyelid, nipple retention, descent of testis, and separation of the prepuce in the BADGE treated group showed no difference in comparisons with the control group. AGD and adjusted AGD (mm/kg) for general developmental items in BADGE 375 mg/kg/day treated pups tended to be longer than in controls, however, these differences were not statistically significant. Relative weights of adrenal gland, lung (p<0.05), brain, epididymis, prostate, and testis (p<0.01) were heavier than in control in measures at PND 9 weeks. There were no significant changes in comparisons of histological findings of these organs. Loss of spermatids was observed in the seminiferous tubule at PND 9 weeks, but no weight changes were observed. The plasma estrogen levels were similar in the control and treatment groups at PND 3, 6 and 9 weeks. The plasma testosterone levels in the control group tended to increase with age. However, in the BADGE 375 mg/kg/day treated male pups it did not tend to increase. Conclusions : These findings suggest that BADGE is a chemical that has developmental effects consistent with it being an endocrine disruptor.

• 한국환경농학회지
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• 제39권4호
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• pp.375-383
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• 2020

BACKGROUND: Bisphenol A (BPA) is a chemical widely used in polycarbonate plastics, epoxy resins. BPA is an endocrine disruptor. Residue of BPA in agricultural environments is a major concern. The objective of this study was to understand the characteristics of the uptake and distribution of BPA and its metabolites introduced into the agricultural environment to crops, and to use it as basic data for further research on reduction of BPA in agricultural products. METHODS AND RESULTS: This study established the analysis method of BPA and its metabolites in soil and crops, and estimated the intake of BPA and its metabolites from lettuce (Lactuca sativa) grown in sandy loam and loam soil, which are representative soils in Korea. The two major metabolites of BPA were 4-hydroxyacetophenone (4-HAP) and 4-hydroxybenzoic acid (4-HBA). BPA, 4-HAP and 4-HBA have been analyzed by using liquid chromatography tandem mass spectrometry (LC-MS/MS). These substances were detected in sandy loam and loam soil, indicating that certain portions of BPA were converted to 4-HAP and 4-HBA in the soil; however, it was observed that only 4-HBA migrated to lettuce through the roots into crops. CONCLUSION: The uptake residues showed the BPA and 4-HAP were not detected in lettuces grown on sandy loam (SL) and loam (L) soil treatments that were applied with of 10 ng/g, 50 ng/kg and 500 ng/g of BPA. However, the 4-HBA was detected at the level of 7 ng/g and 11 ng/g in the lettuce grown in sandy loam and loam soil that were treated with the 500 ng/g of BPA, respectively, while the 8 ng/g of 4-HBA was measured in the lettuce cultivated in the loam that was treated with 100 ng/g of BPA. This result presents that the BPA persisting in the soil of the pot was absorbed through the lettuce roots and then distributed in the lettuce leaves at the converted form of 4-HBA, what is the oxidative metabolite of BPA.

• 한국재료학회지
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• 제3권3호
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• pp.272-275
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• 1993

To modify the toughness of epoxy for matrix, succinonitrile(SN) was introduced to diglycidy1 ether of bisphenol-A (DGEBA)/methylene dianiline(MDA)system. Cure reaction mdchanism of the DGEBA/MDA/SN system was strdied through Fourier transform infrared(FT-IR) spectrometry. As a result, the reaction of nitrile group of SN with secondary amine and with hydroxy1 group prevented the reaction of hydroxy1 group with epoxide group from crossoinding. Nitrile groups produced amide group by reacting with hydroxy1 groups and made a lowered crosslind density in chain networks.

• Biomolecules & Therapeutics
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• 제25권5호
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• pp.545-552
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• 2017

Increasing concern is being given to the association between risk of cancer and exposure to low-dose bisphenol A (BPA), especially in young-aged population. In this study, we investigated the effects of repeated oral treatment of low to high dose BPA in juvenile Sprague-Dawley rats. Exposing juvenile rats to BPA (0, 0.5, 5, 50, and 250 mg/kg oral gavage) from post-natal day 9 for 90 days resulted in higher food intakes and increased body weights in biphasic dose-effect relationship. Male mammary glands were atrophied at high dose, which coincided with sexual pre-maturation of females. Notably, proliferative changes with altered cell foci and focal inflammation were observed around bile ducts in the liver of all BPA-dosed groups in males, which achieved statistical significance from 0.5 mg/kg (ANOVA, Dunnett's test, p<0.05). Toxicokinetic analysis revealed that systemic exposure to BPA was greater at early age (e.g., 210-fold in $C_{max}$, and 26-fold in AUC at 50 mg/kg in male on day 1 over day 90) and in females (e.g., 4-fold in $C_{max}$ and 1.6-fold in AUC at 50 mg/kg vs. male on day 1), which might have stemmed from either age- or gender-dependent differences in metabolic capacity. These results may serve as evidence for the association between risk of cancer and exposure to low-dose BPA, especially in young children, as well as for varying toxicity of xenobiotics in different age and gender groups.