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61.
Biodegradation of [A‐ring 14C] Estrone (E1), 17β‐estradiol (E2), and 17α‐ethinylestradiol (EE2) to 14CO2 was investigated under light and dark conditions in microcosms containing epilithon or sediment collected from Boulder Creek, Colorado. Mineralization of the estrogen A‐ring was observed in all sediment treatments, but not epilithon treatments. No difference in net mineralization between light and dark treatments was observed for 14C‐E2. Net mineralization of 14C‐E1 and 14C‐EE2 was enhanced in light treatments. Extents of 14CO2 accumulation and rates of mineralization were significantly greater for E2 than E1 under dark conditions, but were comparable under light conditions. These results indicate substantial differences in the uptake and metabolism of E1 and E2 in the environment and suggest biorecalcitrance of E1 relative to E2 in light‐limited environments. The extent of 14CO2 accumulation and rate of mineralization for EE2 in dark treatments were less than half of that observed for E2 and generally lower than for E1, consistent with previous reports of EE2 biorecalcitrance. However, 14CO2 accumulation and rates of mineralization were comparable for EE2, E2, and E1 under light conditions. These results indicate photoactivation and/or phototransformation/photodegradation processes can substantially enhance heterotrophic biodegradation of estrogens in sunlit environments and may play an important role in estrogen transport and attenuation.  相似文献   
62.
近年来,内分泌干扰物因损坏生物的内分泌系统而引起人们的广泛关注。其中甾体雌激素(SEs)由于具有极强的内分泌干扰能力,在极其微量的情况下便可对生态系统及人和动物的健康产生不可预测的危害,而城市污水处理厂排放的剩余污泥是环境中该类化合物的重要来源。文章结合最近国内外的研究成果,指出了研究内分泌干扰物在城市污水处理厂剩余污泥处理过程中归趋的重要性,重点总结了有关雌酮、17β-雌二醇、雌三醇、17α-乙炔雌二醇等甾体雌激素在城市污水处理厂污泥处理过程中归趋的主要研究进展,包括4种甾体雌激素的基本理化性质、城市污泥处理系统各处理单元中雌激素的背景含量、主要污泥处理过程对雌激素的去除效果及其机制等,并展望了今后该方面的研究前景、热点和趋势。  相似文献   
63.
作为一种新兴的环境污染物,环境中的雌激素存在于各种介质中,并且已经被证实对生物存在危害。结合国内外的研究成果,综述了不同种类的环境雌激素在我国天然水体中污染现状以及环境雌激素对人类、水生生物和微生物的生态效应。在此基础上,对我国未来开展环境雌激素相关研究和如何应对环境雌激素污染问题进行了展望。  相似文献   
64.
针对天然水体常见的重金属-有机污染物复合污染问题,探讨水体中普遍存在的溶解性有机质(DOM)对有机污染物降解的影响.采集黄河花园口断面水样,模拟天然水体中DOM质量浓度变化,研究了17β-雌二醇(E2)单一污染体系和Cu(Ⅱ)-E2复合污染体系中DOM对E2降解的影响,用环境扫描电镜、傅里叶变换红外光谱和X射线光电子能谱等手段分析了Cu(Ⅱ)-E2复合污染体系中DOM与Cu(Ⅱ)的作用机理.结果表明:在E2单一污染体系中,DOM明显促进E2降解,E2降解速率常数由0.062 d-1提高到0.430 d-1;在Cu(Ⅱ)-E2复合污染体系中,DOM与Cu(Ⅱ)络合,改变了Cu(Ⅱ)的沉淀形态,降低了Cu(Ⅱ)对微生物的抑制作用,因此,E2降解速率常数由0.006d-1提高到0.030 d-1.  相似文献   
65.
The possible effects of a natural substance amygdalin and its combination with the mycotoxin deoxynivalenol (DON) on the steroid hormone secretion (progesterone and 17-β-estradiol) by porcine ovarian granulosa cells (GCs) were examined in this in vitro study. Ovarian GCs were incubated without (control group) and with amygdalin (1, 10, 100, 1,000 and 10,000 μg mL1), or its combination with DON (1 μg mL1) for 24 h. The release of steroid hormones was determined by ELISA. The progesterone secretion by porcine ovarian GCs was not affected by amygdalin in comparison to the control. However, the highest amygdalin dose (10,000 μg mL1) caused a significant stimulation of the 17-β-estradiol release. A combination of amygdalin with DON significantly (P < 0.05) increased the progesterone release at all concentrations. Similarly, a stimulatory effect of amygdalin co-administered with DON was detected with respect to the 17-β-estradiol secretion at the highest dose (10,000 μg mL1) of amygdalin and 1 μg mL1 of DON. Noticeable differences between the effects of amygdalin alone and its combination with DON on the progesterone release were detected. In contrast, no differences between the stimulatory effects of amygdalin and its combination with DON on the 17-β-estradiol synthesis by porcine GCs were observed. Findings from this in vitro study did not confirm the expected protective effect of amygdalin on mycotoxin induced reprotoxicity. Our results indicate that the stimulatory effect of amygdalin combined with DON on the progesterone release was clearly caused by the DON addition, not by the presence amygdalin per se. On the other hand, the stimulation of 17-β-estradiol production was solely caused by the presence of amygdalin addition. These findings suggest a possible involvement of both natural substances into the processes of steroidogenesis and appear to be endocrine modulators of porcine ovaries.  相似文献   
66.
介绍了进行环境雌激素检测和筛选的3种方法:鱼类卵黄蛋白原诱导实验法、重组基因酵母检测法和酵母双杂交法,着重介绍了这3种方法的基本原理、具体操作、适用条件及应用现状.卵黄蛋白原诱导实验是根据正常雄性体内不会含有卵黄蛋白原,环境雌激素能刺激卵生动物肝细胞产生卵黄蛋白原,可通过测定动物体内合成的卵黄蛋白原含量来评价其活性.重组基因酵母法是根据环境雌激素能刺激转化酵母的报告基因表达,以表达的β-半乳糖苷酶的量为依据来判断雌激素活性的大小.酵母双杂交法是在重组基因酵母法的基础上,引入了辅激活蛋白,通过检测雌激素受体和辅激活蛋白之间的相互作用来评价环境雌激素的活性.这3种方法均具有灵敏、简便、快速、经济的优点,同时既可以定性检测又可以定量检测,是目前进行环境中雌激素类物质安全检测与监测的重要手段.  相似文献   
67.
环境雌激素对水生动物的影响研究进展   总被引:12,自引:0,他引:12  
杨再福  赵晓祥 《生态环境》2005,14(1):108-112
水环境是环境雌激素的最大储存库。环境雌激素通过食物的传递进入动物体内,类似于雌激素的功能。环境雌激素可导致水生动物性别特征丧失和后代不能繁殖;可引起水蚤性别比例失调,蜕皮率下降,导致软体动物性畸形和超雌性化现象;导致鲤鱼等生殖器畸形,引起鱼类种群生存力和资源量下降。壬酚(NP)、双酚A(BPA)和E2在河水、水生附着生物和底栖生物之间的生物积累与放大倍数在18~1200倍之间,环境激素通过食物链的生物放大作用比通过水体的传递对鱼类等水生生物的危害更大,并且在河流等的枯水期对水生动物的影响更大。文章讨论了环境雌激素的降解与研究前景。  相似文献   
68.
Background, Goals and Scope In response to concerns that have been raised about chemical substances that may alter the function of endocrine systems and result in adverse effects on human health, an OECD initiative was undertaken to develop and validate in vitro and in vivo assays to identify chemicals that may interfere with endocrine systems of vertebrates. Here we report on studies that were conducted to develop and standardize a cell-based screening assay using the H295R cell line to prioritize chemicals that may act on steroidogenic processes in humans and wildlife. These studies are currently ongoing as part of the ‘Special Activity on the Testing and Assessment of Endocrine Disruptors’ within the OECD Test Guidelines Program to review, develop, standardize, and validate a number of in vitro and in vivo toxicological assays for testing and assessment of chemicals concerning their potential to interact with the endocrine system of vertebrates. Study Design Six laboratories from five countries participated in the pre-validation studies. Each laboratory tested the effects of three model chemicals on the production of testosterone (T) and estradiol (E2) using the H295R Steroidogenesis Assay. Chemicals tested were well described inducers or inhibitors of steroidogenic pathways (forskolin, prochloraz and fadrozole). All experiments were conducted in 24 well plates following standard protocols. Six different doses per compound were analyzed in triplicate per plate. A quality control (QC) plate was run in conjunction with the chemical exposure plate to account for inter-assay variation. Each chemical exposure was conducted two or three times. Results All laboratories successfully detected increases and/or decreases in hormone production by H295R cells after exposure to the different model compounds and there was good agreement in the pattern of response for all groups. Forskolin increased both T and E2 while fadrozole and prochloraz decreased production of both hormones. All chemicals affected hormone production in a dose-dependent manner with the exception of fadrozole which caused maximum inhibition of E2 at the two least concentrations tested. Some inter-laboratory differences were noted in the alteration of hormone production measured in chemically exposed cells. However, with the exception of the production of T measured at one laboratory in cells exposed to forskolin, the EC50s calculated were comparable (coefficients of variation 34–49%) for all hormones. Discussion and Perspectives The results indicated that the H295R Steroidogenesis Assay protocol was robust, transferable and reproducible among all laboratories. However, in several instances that were primarily related to one laboratory there were unexplained minor uncertainties related to the inter-laboratory hormone production variation. Based on the findings from this Phase 2 prevalidation study, the H295R Steroidogenesis Assay protocol is currently being refined. The next phase of the OECD validation program will test the refined protocol among the same group of laboratories using an extended set of chemicals (∼30) that will include positive and negative chemical controls as well as a broad spectrum of different potential inducers and inhibitors of steroidogenic pathways. Submission Editor: Dr. Carsten Brühl (bruehl@uni-landau.de)  相似文献   
69.
辽东湾海水中甾体雌激素的检测及生态风险评价   总被引:1,自引:0,他引:1       下载免费PDF全文
建立了SPE-丹酰化衍生-UPLC-MS/MS海水中雌激素的高灵敏度分析方法,对辽东湾海水中甾体雌激素的浓度水平及分布进行了调查并对其潜在的生态风险进行了评估.结果表明:辽东湾海水样品中检出雌酮,17β-雌二醇,17α-雌二醇,雌三醇和17α-乙炔基雌二醇的浓度分别为(0.714±0.407),(0.089±0.077),(0.009±0.011),(0.008±0.008),(0.001±0.003)ng/L.雌激素浓度在大辽河入海口区域最高,双台子河入海口次之,大凌河及小凌河入海口区域最低.辽东湾海水中的17β-雌二醇等当量浓度(EEQ-E2β)为0.562±0.327ng/L,导致野生梭鱼雌雄同体发生的概率约为0.83%,不足以解释该海域野生梭鱼雌雄同体的高发生率.为了有效管理该海域的环境安全,有必要对原因物质进行进一步解析.  相似文献   
70.
天然类固醇雌激素源解析、环境行为及其污染控制   总被引:2,自引:0,他引:2  
天然类固醇雌激素是一种在生物体内具有极强雌激素效应的内分泌干扰物,其在环境中的广泛存在严重影响野生动物尤其是鱼类的正常生长和发育,对环境生态系统所产生的破坏也日趋严重,然而其危害依然没有引起足够的重视。文章研究在阐述天然类固醇雌激素基本理化性质和环境存在形态的基础上,解析其在人类和畜禽的环境来源,分析其在地表水和地下水的污染状况以及环境迁移和生物积累等环境行为,并综合探讨了现今较为常见的如活性污泥法、光降解法以及微滤、纳滤和反渗透等与天然类固醇雌激素相关的污染控制技术,以期为天然类固醇雌激素的毒理性质、污染现状及相关控制方法的深入研究提供支撑。在此基础上,提出深入天然类固醇雌激素微量检测技术研究、加强国家行政管理层面上的污染控制等已十分急迫。  相似文献   
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