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231.
Endocrine disrupting compounds (EDCs), pharmaceuticals and personal care products (PPCPs) have attracted much attention due to widespread contamination in aquatic environment. In this study, we determined 13 EDCs and PPCPs in fish blood, bile and muscle by using gas chromatography-mass spectrometry (GC-MS). The limits of quantitation (LOQ) were in the ranges of 0.23–2.54, 0.22–2.36 ng·mL−1, and 0.24–2.57 ng·g−1 dry weight (dw) for fish blood, bile and muscle, respectively. Recoveries of target compounds spiked into sample matrices and passed through the entire analytical procedure ranged from 65% to 95%, from 60% to 92% and from 62% to 91% for blood, bile and muscle, respectively. The methods were applied to the analysis of fish from a lake in California. Target compounds were relatively low in bile, and only bisphenol A (BPA) and diclofenac were measurable near the LOQ. Seven of 13 compounds were detected in blood, with total concentrations up to 39 ng·mL−1. Only BPA was frequently found in muscle, with mean concentration of 7.26 ng·g−1 dw. The estimated daily intake of BPA through fish consumption for U.S. resident was significantly lower than the tolerable daily intake recommended by the European Food Safety Authority. This study showed that the exposure to the bisphenol A from fish diet is unlikely to pose a health risk.  相似文献   
232.
《环境化学》2012,31(6)
甲状腺激素在脊椎动物新陈代谢、生长发育与繁殖等生理过程中起着重要的调节作用.环境污染物种类和数量不断增加,其中有很多污染物具有环境内分泌干扰的作用.甲状腺对环境污染物具有极敏感的反应,污染物不仅会引起滤泡及滤泡细胞大小、滤泡细胞数量和滤泡腔中胶质含量的改变,影响到甲状腺激素合成、分泌、转运以及代谢中多种酶的表达和活性变化,还参与和甲状腺激素的竞争性结合,进而影响到机体中由甲状腺激素调节的各项生理功能,甚至会导致机体趋于死亡.由于两栖类幼体——蝌蚪的变态发育阶段直接受到甲状腺激素的调控,现已被确认为筛选和研究环境内分泌干扰物的首选生物检测指示动物.  相似文献   
233.
环境内分泌干扰化合物干扰胰岛素分泌潜在作用机理   总被引:2,自引:1,他引:1  
不断升高的糖尿病发病率在全球范围内引起广泛关注,流行病学调查显示糖尿病发病率的增加与环境内分泌干扰化合物使用量增大之间存在显著相关,环境内分泌干扰化合物可能增加糖尿病发病风险,是影响糖尿病的危险因素。在此背景下,综述了环境内分泌干扰化合物暴露与糖尿病发病之间的流行病学关系;环境内分泌干扰化合物暴露对胰岛β细胞胰岛素分泌的调节、高胰岛素效应及其潜在的作用机理,表明影响胰岛素分泌是环境内分泌干扰化合物调节代谢,诱发糖尿病的重要作用机制。  相似文献   
234.
Effluents from wastewater treatment plant (WWTP) have been reported to have a broad spectrum of endocrine disrupting compounds (EDCs). The majority of studies have focused on the occurrence of estrogenic activity, while ignoring nuclear hormone receptors (NRs) pathways. In the present study, a battery of in vitro yeast bioassays and a cell bioassay, including antagonistic and agonistic effects on estrogen receptor (ER), androgen receptor (AR), progesterone receptor (PR), estrogen- related receptor (ERR) and aryl hydrocarbon receptor (AHR), were conducted to evaluate the removal efficien- cies of EDCs by different treatment processes of a WWTP located in Beijing. Estrogenic, anti-estrogenic, anti- androgenic, anti-progesteronic, anti-ERR and the activa- tion of AHR activities were detected in samples from all treatment processes and the receiving water. The concen- tration of estrogenic contaminants with estradiol (E2) equivalent concentrations ranged from 0.82 x 10-9 to 3.54 x 10 9g Ee_EQ.L-1. The concentration of anti-estrogenic contaminants with 4-hydroxytamoxifen (4-OHT) equiva- lent concentrations ranged from 1.24 × 10-6 to 2.36 x 10-6 g 4-OHT-EQ.L-1. The concentration of anti-androgenic contaminants ranged from 2.21 x 10-s to 3.52 × 10-6g flutamide-EQ. L-1. The concentration of anti-progesteronic contaminants ranged from 3.15 x 10^-5 to 2.71 x 10^-4g RU486-EQ. L-1. The concentration of anti-ERR contami- nants ranged from 7.09 x 10-5 to 6.50 x 104 g 4-OHT-EQ × L^-10. The concentration of AHR activators ranged from 1.7 × 10-10 to 3.4 × 10^-10g TCDD-EQ-L-1. These processes including secondary clarifier, coagulation, as well as coal and sand filtration could eliminated 67.2% of estrogenic contaminants, 47.0% of anti-estrogenic contaminants, 98.3% of anti-androgenic contaminants, 88.4% of anti- progesteronic contaminants, 65.4% of anti-ERR contami- nants and 46.9% of AHR activators. WWTP effluents contain multiple receptor disruptors may have very complex adverse effects on exposed organisms.  相似文献   
235.
Bo Lü 《毒物与环境化学》2013,95(5):1027-1034
In order to determine the effects of nonylphenol (NP) on endocrine regulation-associated gene expression profiles in whole brain of F1 generation rats, mRNA extracted from the brain of 2-day old F1 generation rats whose F0 male generation was treated with NP. The mRNA was then reversely transcribed to cDNA and labeled with cy5 and cy3 fluorescence. Subsequently, cDNA probes were hybridized to the Mouse40S cDNA microarray and the fluorescent signals of cy5 and cy3 were scanned and analyzed. Sixteen genes were identified which expressed differently, including 13 that were down-regulated in which 4 were related to brain regulation of endocrine function. Data suggest that NP mainly affects metabolism and synthesis of steroid hormone in various ways and disturbs the reproductive function of male rats when administered perinatally.  相似文献   
236.
The associations between blood organohalogen contaminant (OHC) concentrations and thyroid gland histology were studied in 10 adult female glaucous gulls (Larus hyperboreus) from the Norwegian Arctic (Bjørnøya) during the incubation period. This histological investigation was undertaken as previous glaucous gull studies from the same area reported negative relationships between circulating OHC concentrations and thyroid hormone levels. Organohalogen concentrations have previously been associated with altered blood plasma thyroid hormone concentrations, as a result of parenchymal thyroid gland alterations and perturbation of the hypothalamic-pituitary-thyroid (HPT)-axis. In this study, PCB (range: 186–1027 ng g?1ww), DDT (77–203 ng g?1ww) and chlordane (18–65 ng g?1ww) concentrations dominated the blood plasma OHC profile in incubating female glaucous gulls. High density of small follicles accompanied by follicular epithelial cell proliferations was seen in thyroid glands in seven of 10 gulls. Focal thyroiditis and nodular hyperplasia were found in two birds. No significant differences in plasma OHC concentrations were noted between gulls exhibiting high density of small follicles and cell proliferations and those birds not showing histological changes. Based on these findings, data suggest that the histological changes in thyroid glands of OHC-contaminated female glaucous gulls may be due to natural variance, although an OHC-induced thyroid stimulating hormone (TSH) perturbation resulting in epithelial cell hyperplasia and increased follicular density cannot be ruled out and remains to be verified. Hence, a large-scale histological study is required, in order to elaborate the potential linkage between changes in thyroid gland histology, OHC exposure and regulation of the HPT-axis in the Arctic-breeding glaucous gull.  相似文献   
237.
East Greenland polar bears (Ursus maritimus) are among the mammals with the highest bioaccumulated concentrations of organohalogen contaminants (OHCs). Since Greenlanders in this region ingest significant quantities of adipose tissue from polar bears and also ringed seals (Pusa hispida), initial conservative estimates of the daily oral exposure to this chemical cocktail are thus presented. The tolerable daily intake was exceeded approximately five-fold for polychlorinated biphenyls and chlordane pesticides and metabolites, while the estimated daily toxic equivalent (TEQ) (based on the 2,3,7,8-tetrachlorodibenzo-rho-dioxin toxicity equivalence factors) for East Greenland subsistence hunters was three- to ten-fold higher than the WHO ∑TEQ guidelines even though the estimations were conservative. The daily oral OHC exposure from polar bear and ringed seal blubber consumption is markedly high and needs to be reduced in order to remove this co-factor with respect to the influence on the development of chronic diseases. Furthermore, it is warranted that a physiologically based pharmacokinetic model for Greenlander's exposure to OHCs is constructed and that risk quotients calculated to estimate the threats to health for East Greenland subsistence hunters.  相似文献   
238.
Abstract

Atrazine, an endocrine-disrupting compound and environmental pollutant, can have adverse effects on amphibian reproductive development and function. To determine the effects of atrazine on anuran gonadal development, Lithobates pipiens larvae were exposed from Gosner stage 25 through 1-month post metamorphosis to 0, 2, 20, or 200?μg/L atrazine or estradiol. Exposure to atrazine did not markedly alter tadpole growth, development, gonadal histology, or reproductive steroidogenesis. Testicular ovarian follicles appeared in L. pipiens metamorphs following all treatments, including controls, whereas ovotestes occurred only in positive controls. Testicular ovarian follicles may be a natural ontogenetic occurrence in this species while ovotestes indicate disruption in development. Establishing the normal pattern of reproductive development for anuran species and conducting comparisons in fully sexually differentiated animals is necessary to clarify the influence of endocrine disrupting compounds.  相似文献   
239.
Regeneration is a vital physiological process for survival of adult organisms. Bisphenol A (BPA), diethystilbestrol (DES), 17α-ethinylestradiol (EE2), and 17β-estradiol (E2) were examined for their effects on head formation in decapitated freshwater planarians (Dugesia japonica). The median lethal concentration of the test chemicals and the median inhibitory concentration for decapitated planarians and different regenerative endpoints, were determined for 3–7 d of exposure. For planarian head regeneration, the no-observed-effect level of BPA and DES was 0.05 mg L?1 and 1 mg L?1 for EE2 and E2. The effects of BPA, DES, and EE2 on asexual planarian regeneration did not correspond with the order of their estrogenic potencies, suggesting that the effects, at least partially, were due to general toxicity rather than their estrogenicity. In view of the published data on concentrations of xenoestrogens in water bodies versus the nominal levels tested here, this study suggests that the current environmental levels of BPA, DES, EE2, and E2 have no immediate adverse effects on freshwater planarian regeneration.  相似文献   
240.
长江中下游某Unitank污水处理厂去除雌激素的效果分析   总被引:1,自引:0,他引:1  
以长江中下游地区某实际运行的Unitank污水处理厂为研究对象,跟踪监测了其进、出水类固醇雌激素(SE)的浓度水平,考察了雌激素去除效果随时间的变化规律,并分析了不同处理工段对雌激素去除的贡献。结果表明:污水厂进水中雌酮(E1)、17β-雌二醇(E2)、17α-乙炔基雌二醇(EE2)的浓度分别为32.4~89.0,19.4~78.0和12.3~45.0 ng/L,且夏季浓度高于冬季;Unitank工艺对E1、E2、EE2的去除率分别为21.3%~77.0%,23.4%~73.5%和25.2%~68.1%。SE去除主要依靠好氧生物降解实现,物理沉降(沉砂或沉淀)对SE的去除贡献较小。温度是影响SE去除的重要因素之一,较高的温度有利于SE的去除。  相似文献   
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