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61.
The potential for negative effects caused by endocrine disrupting chemicals (EDCs) release into the environment is a prominent concern and numerous research projects have investigated possible environmental fate and toxicity. However, their sorption behavior by size fractions of soil and sediment has not been systematically represented. The sorption of bisphenol A (BPA), 17α-ethinyl estradiol (EE2) and phenanthrene (Phen) by different size fractions of soil and sediment were investigated. Sorption isotherms of EE2, BPA, and Phen by size fractions of soil (SL) and sediment (ST) were well fitted to the Freundlich model. The positive correlation between EE2, BPA and Phen sorption capacity (log Kd) of size fractions and their organic carbon (OC) content suggests that OC of size fractions in SL and ST should regulate sorption, while the surface area (SA) of size fractions may not account for sorption of EE2, BPA and Phen. Each size fraction of ST had higher sorption capacity (Kd or KOC) of EE2 and BPA than that of SL due to their difference in the polarity of organic matter (OM) between terrestrial and aquatic sources. Sorption capacity logKd for size fractions of SL and ST did not follow the order: clay > silt > sand due to the difference in OM abundance and composition between the size fractions. Large particle fractions of ST contributed about 80% to the overall sorption for any EE2, BPA, and Phen. This study was significant to evaluate size fractions of soil and sediment as well as their associated OM affecting EE2 and BPA sorption processes. 相似文献
62.
沉水植物附生细菌可能具有降解转化水体中双酚A(BPA)能力从而影响该污染物在环境中的归趋.以轮叶黑藻为代表,分离筛选其BPA降解附生菌,结果共获得22株,在接种量为1×108个/mL,37℃下72h对BPA的去除率为11.46%~25.06%.选择降解率最高的3株细菌B12、B14和B23,采用16S rDNA鉴定,结合生理生化反应和形态观察,3株细菌分别为属于Lysinibacillus sp.(杆菌属),Brevibacterium sp.(短杆菌属)和Ochrobactrum sp.(苍白杆菌属).将3株菌株添加至轮叶黑藻无菌苗体系中,发现BPA去除率显著下降(P<0.05).物理去除部分野生轮叶黑藻表面部分附生细菌后,BPA去除率反而上升(约5%).综合本研究结果,沉水植物附生细菌具有降解BPA的能力,但在沉水植物-附生生物体系去除BPA过程中贡献较小(约为23%,2d),植物本身起关键作用. 相似文献
63.
双酚A体外类雌激素活性评价及其作用机制的初步研究 总被引:11,自引:0,他引:11
采用体外MCF-7细胞增殖试验检测了双酚A(BPA)的类雌激素活性,并用生长曲线分析、细胞周期分析、他奠昔芬拮抗试验和凋亡检测对其作用机制进行了初步探讨。结果显示BPA有明显刺激MCF-7细胞增殖的类雌激素活性;细胞周期分析BPA组细胞增殖指数均明显高于溶剂对照组;BPA刺激MCF-7细胞增殖的类雌激素活性可被Tam拮抗:BPA能明显抑制MCF-7细胞凋亡的发生。结果提示BPA刺激MCF-7细胞增殖的类雌激素活性作用机制可能是BPA与雌激素受体结合后,影响细胞增殖及细胞凋亡过程,从而产生一系列生物效应。 相似文献
64.
双酚A对稻田土壤细菌群落特征及土壤酶活的影响 总被引:1,自引:0,他引:1
采用FQ-PCR(实时荧光定量PCR)、PCR-DGGE(PCR扩增和变性梯度凝胶电泳)技术和土壤酶学研究法对不同浓度双酚A污染的稻田土壤细菌群落特征及土壤酶活性进行了研究.结果表明:经双酚A高浓度处理〔即w(双酚A)分别为200和1 000 mg/kg〕的稻田土壤细菌数量显著低于未受污染的对照(CK)和低浓度处理〔w(双酚A)为50 mg/kg〕,并且高浓度处理分别较CK处理(3.64×109 g-1)下降90.44%和99.83%.细菌16S rDNA V3可变区DGGE图谱表明,受双酚A污染的土壤明显产生了数条特征性条带.UPGMA(非加权组平均法)聚类分析进一步表明,双酚A污染明显改变了稻田土壤的细菌群落组成.2次采样土壤总体酶活性参数均为CK>w(双酚A)为50 mg/kg处理>w(双酚A)为200 mg/kg处理>w(双酚A)为1 000 mg/kg处理.可见,高浓度的双酚A污染明显影响稻田土壤细菌数量以及细菌优势菌群,使农田土壤细菌群落多样性发生变化. 相似文献
65.
珠江三角洲两条主要河流沉积物中的典型内分泌干扰物污染状况 总被引:1,自引:0,他引:1
为了调查珠江三角洲河流沉积物中典型内分泌干扰物的污染状况,采用超声提取-衍生化-GC/MS法研究了双酚A(BPA)、雌酮(E1)、雌二醇(E2)、己烯雌酚(DES)、17α-乙炔雌二醇(EE2)、雌三醇(E3)等典型内分泌干扰物在珠江广州河段和东江东莞河段表层沉积物中的质量分数水平、分布特征,并对其来源进行了分析。结果显示,BPA在所有样品中均有检出,E1和E2的检出率分别为72%和61%,其质量分数(以干质量计)分别在14.3~429.5 ng.g-1之间(中值为79.5 ng.g-1)、〈1.3~10.9ng.g-1之间(中值为3.4 ng.g-1)和〈0.9~2.6 ng.g-1之间(中值为1.6 ng.g-1);其余几种雌激素均未被检出。东江东莞河段沉积物中BPA的污染水平整体高于珠江广州河段,而天然雌激素的污染状况则是珠江广州河段更为严重。3种化合物的质量分数总体呈现出沿河口方向降低的分布特征,这可能与沿岸工业废水和生活污水不规则排放以及水动力条件有关。BPA、E1、E2的质量分数均与沉积物总有机碳(TOC)质量分数呈正相关,表明有机质是控制沉积物中内分泌干扰物分布的一个重要因素。 相似文献
66.
为了调查珠江三角洲河流沉积物中典型内分泌干扰物的污染状况,采用超声提取-衍生化-GC/MS法研究了双酚A(BPA)、雌酮(E1)、雌二醇(E2)、己烯雌酚(DES)、17α-乙炔雌二醇(EE2)、雌三醇(E3)等典型内分泌干扰物在珠江广州河段和东江东莞河段表层沉积物中的质量分数水平、分布特征,并对其来源进行了分析。结果显示,BPA在所有样品中均有检出,E1和E2的检出率分别为72%和61%,其质量分数(以干质量计)分别在14.3~429.5 ng.g-1之间(中值为79.5 ng.g-1)、<1.3~10.9ng.g-1之间(中值为3.4 ng.g-1)和<0.9~2.6 ng.g-1之间(中值为1.6 ng.g-1);其余几种雌激素均未被检出。东江东莞河段沉积物中BPA的污染水平整体高于珠江广州河段,而天然雌激素的污染状况则是珠江广州河段更为严重。3种化合物的质量分数总体呈现出沿河口方向降低的分布特征,这可能与沿岸工业废水和生活污水不规则排放以及水动力条件有关。BPA、E1、E2的质量分数均与沉积物总有机碳(TOC)质量分数呈正相关,表明有机质是控制沉积物中内分泌干扰物分布的一个重要因素。 相似文献
67.
环境雌激素双酚A(BPA)在环境中广泛存在,具有剂量小、潜伏期长、接触频繁等特点,是危害极大的一类环境污染物。文章综述了BPA对生物生殖系统、组织器官、免疫系统、生长发育的毒理学效应,重点阐述了复合污染体系BPA与其他物质的联合毒效应等方面国内外研究进展。并对其影响内分泌系统、雌激素受体(ER)介导的通路、拮抗雄激素受体(AR)介导的通路以及影响组织内的酶等作用机制进行了扼要的阐述。提出了下一步的研究方向:寻找和探索有效的生物降解物种,找到高效、经济合理的消除路径去除环境介质中残留的BPA及其代谢产物,建立有效预防体系。 相似文献
68.
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