本研究以两栖类模式生物—非洲爪蟾的胚胎为受试生物，以珠江三角洲和天津市大沽排污河为代表区域，建立了沉积物有机提取液致畸毒性的生物测试方法。该方法应用FETAX(Frog Embryo Teratogenesis Assay—Xenopus)实验，采用活体暴露的方式对囊胚期非洲爪蟾胚胎进行培养，以暴露96h后非洲爪蟾胚胎的畸形率、体长、体重、存活率为测试终点，研究了沉积物有机提取液对非洲爪蟾胚胎的致畸效应及生长、发育的影响，并筛选出了最灵敏的毒性指标。同时，对沉积物有机提取液进行了传统的发光细菌生物毒性测试（Microtox检验，测试终点为EC50），研究了沉积物的综合急性毒性效应。通过对比两种生物测试方法，评价了应用非洲爪蟾胚胎发育的方法研究沉积物致畸毒性的可行性和优势。通过对两研究区域分别进行FETAX实验，揭示了应用非洲爪蟾胚胎发育研究沉积物致畸毒性的普遍适用性。进一步地，以大沽排污河沉积物为对象，在沉积物有机提取液的基础上根据极性差异分级提取得到正己烷相提取液和丙酮相提取液，对全相提取液和两种分级提取液分别进行FETAX实验和Microtox检验实验，进一步探讨了沉积物有机全相提取液和分级提取液的生物毒性差异。结果显示：珠江三角洲地区不同区域的沉积物有机提取液的生物毒性：所选有机提取液浓度范围内，相比番禺区、南沙区而言，广州市区对非洲爪蟾胚胎发育影响最大，故胚胎毒性排序：广州区>番禺区、南沙区。毒性指标中，畸形率、体长较体重、存活率更为灵敏。Microtox检验得到珠江三角洲地区沉积物有机提取液均具有显著的综合急性毒性，但是三个区域间毒性差异不显著。两方法比较而言，FETAX实验中非洲爪蟾胚胎畸形率、体长的灵敏度高于发光菌生物毒性测试方法。大沽排污河不同采样点的沉积物有机提取液的生物毒性：FETAX实验中，所选有机提取液浓度范围内，Site2的三种提取液的对非洲爪蟾胚胎发育影响最大，故胚胎毒性排序：Site2>Site1、Site3。Microtox实验所得结果因提取相而不同。其中，全相提取液、正己烷相提取液：Site1、Site2>Site3。丙酮相提取液：Site2、Site3>Site1。FETAX实验与Microtox检验实验结果相关性分析：就全相提取液而言，无论是珠江三角洲沉积物还是大沽排污河沉积物，EC50与畸形率、体长、体重、存活率均无显著线性关系。正己烷相提取液在浓度为1 g/L时，体长、体重与EC50均显著正线性相关。丙酮相提取液在浓度为10 g/L时，体长、存活率与 EC50显著正线性相关；在浓度为1 g/L时，体重与EC50极显著负线性相关，说明随着对发光菌毒性的增加，对非洲爪蟾胚胎发育体重反而具有促进作用，反映了提取液对不同的受试生物具有不同的致毒机制。EC50与两设定浓度下的提取液的致畸毒性均极显著负线性相关，说明随着提取液致畸毒性的增强，其对发光菌的毒性作用亦增强。大沽排污河三种提取液间的各种毒性差异：两设定浓度下，三种提取液对非洲爪蟾胚胎发育畸形率、存活率均显著相关，无显著性差异。高浓度下，三种提取液对体长、体重抑制毒性显著相关，无显著性差异。但是低浓度下，体长、体重抑制毒性大小排序：丙酮相、正己烷相>全相，表明分级提取液对非洲爪蟾胚胎发育的生长抑制作用大于全相提取液。两浓度下的三种有机提取液对各生物毒性指标的影响相关性分析：对于珠江三角洲，两浓度下的沉积物提取液对体重的影响显著正线性相关，说明该浓度范围内体重也许可以作为具有剂量—效应关系的沉积物毒性生物测试指标。在设定的提取液浓度范围内，对于大沽排污河地区沉积物，全相提取液对体长、体重的影响具有一定的剂量—效应关系，正己烷提取液对畸形率、体长的影响具有一定的剂量—效应关系。丙酮相提取液对畸形率的影响具有一定的剂量—效应关系。因此，沉积物提取液对非洲爪蟾胚胎畸形率、体长、体重的影响具有一定的剂量—效应关系。非洲爪蟾胚胎发育生物毒性测试方法的可行性：应用非洲爪蟾胚胎发育成功评价了珠江三角洲和大沽排污河地区沉积物的致畸毒性效应。珠江三角洲沉积物生物毒性测试中，畸形率、体长是最为灵敏的指标。在大沽排污河沉积物生物毒性测试中，畸形率、体长、体重则是最为灵敏的指标。综合而言，暴露96 h后非洲爪蟾胚胎的的畸形率、体长在所选生物毒性测试指标中灵敏度最高。

In this study, model organism-amphibian Xenopus laevis embryos were applied to develop a method of evaluating the teratogenic potential of sediment organic extract, and the Pearl River Delta and Dagu Drainage River in Tianjin were selected as the study area. Embryos of blastula stage were selected to exposure to the sediment organic extract, after 96 hours, malformation rates, body length, body weight and survival rates were detected using FETAX (Frog Embryo Teratogenesis Assay - Xenopus), and sensitive biological indicators were selected as well. Meanwhile, the Photobacterium phosphoreum (Microtox test, test end point is EC50) was adopted to detect the comprehensive acute toxicity. By comparing two test methods, the feasibility and advantage of FETAX were discussed. Using FETAX, the teratogenic potential of sediment from Pearl River Delta and Dagu Drainage River was evaluated, indicating the universal applicability of this method. Further, on the basis of sediment organic extract from Dagu Drainage River, multi-extract fractions with different polarity were obtained, including hexane fraction and acetone fraction. Thereafter, FETAX and Microtox test were carried out to evaluate the co relationships and differences of toxicity between three kinds of fractions. The results indicated:Toxicity of sediment from different regions of the Pearl River Delta: in selected concentration range(1~10 g/L), compared to Panyu and Nansha district, the teratogenicity and body length inhibition effect of sediment extract from Guangzhou were greater. However, differences of body weight and survival rates were not significant between regions. So the order of toxicity was as follows: Guangzhou>Panyu, Nansha. In addition, Microtox test showed significant comprehensive acute toxicity in all sites of Pearl River Delta, but without significant toxicity differences between regions. It suggested that the teratogenicity and body length inhibition effect in FETAX was more sensitive than the Microtox test in detecting the toxicity potential of sediment.Toxicity of sediment from different sites of Dagu Drainage River: in the FETAX, the embryotoxicity of three kinds of sediment extracts from Site 2 was significantly greater than Site1 and Site3. However, the result was different due to different extracts in the Microtox test. As to the whole extract and hexane fraction, the order of comprehensive acute toxicity was as follows: Site1, Site2>Site3. However, for the acetone fraction, the order of comprehensive acute toxicity was as follows: Site2, Site3>Site1.Correlation analysis between the FETAX and Microtox test: as to the whole extract, for Pearl River Delta or Dagu Drainage River, there was no significant relationship between EC50 and deformity rates, body length, body weight, or survival rates. As to the Hexane fraction, body length, body weight was significantly positive correlated with EC50 at concentration of 1 g/L. At concentration of 10 g/L, there was a significantly positive correlation between body length, survival rates and EC50 for the acetone fraction; however, a significantly negative correlation existed between body weight and EC50 at concentration of 1g/L, indicating that weight growth was promoted as the increase of comprehensive toxicity, reflecting various toxicity mechanisms to different organisms. There was a significantly negative linear correlation between EC50 and deformity rates at both concentration of 10 g/L and 1 g/L, indicating that teratogenicity was consistent with comprehensive acute toxicity. Differences of various biological indicators between three kinds of extracts from Dagu Drainage River: at two concentrations, malformation rates and survival rates between three kinds of extract were significantly correlated, with no significant differences. At high concentration, body length was significantly related to body weight between three kinds of extract, without significant differences. However, at low concentration, the order of growth inhibition toxicity was as follows: acetone, hexane fraction>whole, indicating that the growth inhibition effect of acetone and hexane fractions were greater than the whole extract. Correlation analysis on various biological indicators between the two concentrations for three kinds of extracts, the results were as follows: for the Pearl River Delta, body weights under two concentrations of sediment extract were in a significantly positive correlation, it suggested that body weight could be adopted as a biological indicator to satisfy the dose-response relationship. As to the Dagu Drainage River, both body length and weight showed the dose-response relationship in the whole extract. For the hexane fraction, both malformation rates and body length met the dose-response relationship. While for the acetone fraction, deformity rates satisfied the dose-response relationship. As a whole, the deformity rates, body length and weight may be used in showing the dose-response relationship of sediment toxicity.The feasibility of teratogenic potential studies of sediment using Xenopus laevis embryos: the teratogenic potential of sediment from the Pearl River Delta and Dagu Drainage River were successfully assessed. The most sensitive biological indicators screening in FETAX: in the sediment toxicity test of Pearl River Delta, malformation rates, body length were the most sensitive indicators. However, in the sediment toxicity test of Dagu Drainage River, malformation rates, body length, body weight were the most sensitive indicators. Thus, malformation rates and body length were selected as the most sensitive indicators.