摘 要双酚类化合物(Bisphenols, BPs)在土壤,水体,底泥,室内灰尘等多种环境介质中已有检出,具有潜在的生态健康风险。四溴双酚A(TBBPA)、四溴双酚S (TBBPS)和四氯双酚A(TCBPA)是较常见的双酚类化合物,主要用于阻燃剂。本文旨在阐明不同结构的双酚类化合物对黑斑蛙的雄性生殖毒性和致毒机理。黑斑蛙分别暴露于0,0。001,0。01,0。1,1 mg/L的双酚类化合物(TBBPA、TBBPS和TCBPA),暴露时间为14天,并做试剂空白对照。暴露结束后,采用人工光学显微镜方法测定黑斑蛙的精子数量、精子活性以及精子畸形率;采用透射电镜观察黑斑蛙精巢中精子的形态学变化。结果显示,经TBBPA 、TBBPS和TCBPA 暴露后,黑斑蛙精巢中精子数量显著减少,精子活性显著降低,精子畸形率显著上升;精巢中精子超微结构也不同程度地出现了精子排列顺序不整齐,气泡发生和精子颈部出现肿胀现象。其中,黑斑蛙分别暴露于1mg/L 的TBBPA、TBBPS和TCBPA溶液14天后,其精子数量分别减少了44。6%,34。7%和51。5%,精子活性分别降低了52。3%,39。2%和20。5%,畸形率分别上调5。04,3。87和3。85倍。这反映了 TBBPA、TBBPS和TCBPA均降低了黑斑蛙精子质量和精子的形态学变化。从精子数量指标角度评估,双酚类化合物毒性大小次序为 TCBPA > TBBPA >TBBPS;从总体的生殖毒效应角度评估,双酚类化合物毒性大小次序为TBBPA >TCBPA>TBBPS。因此,结果表明双酚A类化合物可以使黑斑蛙雄性精巢精子质量下降,并使精子发生形态学变化,严重引起雄性黑斑蛙的生殖毒效应。90146
毕业论文关键词:双酚类化合物; 黑斑蛙; 精子质量; 超微结构观察; 生殖毒效应
Abstract Bisphenol compounds (Bisphenols, BPs) have been detected in various environmental media such as soil, water, sediment, indoor dust, etc。, and pose potential ecological risks。 Tetrabromobisphenol A (TBBPA), Tetrabromobisphenol S (TBBPS) and Tetrachlorobisphenol A (TCBPA) are common bisphenol compounds and mainly used as flame retardants。 This study aims to study the male reproductive toxic effects and mechanism of bisphenol compounds in male frogs (Rana nigromaculata)。 Male frogs were respectively exposed to 0, 0。001, 0。01, 1 mg/L bisphenol compounds (TBBPA, TBBPS and TCBPA) for 14 days, and made reagent blank test at the same time。 After end of bisphenol compounds exposure, optical microscope was used to measure the number of sperm, sperm mobility and sperm deformity rate, and transmission electron microscopy was used to observe the morphological changes of sperms in testis。 The results showed that after exposure to TBBPA, TBBPS and TCBPA, the number of sperm and sperm mobility were significantly decreased, and the rate of sperm deformity was significantly increased in the testis of frogs; ultrastructure observation results revealed irregular arrangement of sperms, vacuoles in sperms and swelling damage in sperm necks at different degrees。 Among the results, after frogs were respectively exposed to 1mg/L TBBPA, TBBPS and TCBPA for 14 days, the number of sperm was respectively decreased by 44。6%, 34。7% and 51。5%, sperm mobility was respectively decreased by 52。3%, 39。2% and 20。5%, sperm deformity rate was respectively increased by 5。04-, 3。87- and 3。85-fold。 These results indicated that TBBPA, TBBPS and TCBPA cause a drop in sperm quality and morphological changes of sperms。 The rank order of toxicities of bisphenol compounds were TCBPA > TBBPA >TBBPS From the number of sperm perspective, while the rank order of toxicities of bisphenol compounds were TBBPA >TCBPA>TBBPS from the total reproductive toxicity effect perspective。 Thus, the results suggest that the bisphenol compounds can reduce the sperm quality of male frogs, induce the morphological changes of sperms, and subsequently cause the reproductive toxicity effects of male frogs。