应用重组基因酵母法检测松花江吉林段土壤有机组分甲状腺激素干扰效应

Detection of the thyroid disrupting effect of soil organic extracts from Songhua River basin in Jilin City using recombinant thyroid receptor gene yeast

利用重组甲状腺激素受体（TR）基因酵母，结合土壤样品索氏提取、富集和净化方法，检测松花江吉林段土壤有机组分甲状腺激素干扰效应及其分布特征。测试结果表明：所有样点均未检测出TR诱导效应；部分样点检测出TR抑制效应，检出率为56．25％，最大抑制率为46．00％；采用RIC20值（抑制率为20％时每孔所需要的土壤量，以mg计）表征样点的抑制效应，其RIC20值为0．81～5．34，表明松花江吉林段土壤中存在TR抑制效应污染物，可能具有潜在的环境危害。研究土壤甲状腺激素干扰效应的分布特征发现研究区甲状腺激素干扰效应分布与产业布局相关，TR抑制效应较高的样点主要集中在工业区及养殖区，表明TR抑制效应物质可能来源于工业污染或畜产养殖污染。通过本研究探明了松花江吉林段土壤有机组分的甲状腺激素干扰特征，为该地区土壤污染防治以及风险评价提供了基础的毒理学数据。

Combined with Soxhlet extraction, enrichment and purification, the recombinant thyroid receptor （TR） gene yeast bio- assay was conducted to assess the TR ant/agonistic activities of the organic extracts from soil collected from Songhua River basin in Jilin City, China. The regional distribution characteristics of the thyroid disrupting effect were also analyzed. The results showed that the agonistic activities were not found in all soil samples. However, the antagonistic activities were found in 56.25% of samples and the maximum inhibition activity was 46.00%. The value of RIC20 （the quantity of soil per well that could result in the inhibition activity equals 20 %,rag） was calculated to evaluate the antagonistic activity, which ranged from 0. 81 to 5.34. These results suggest that there are many TR antagonists existing in the soil of the study area, which may have potential environ- mental risks. The results further support that the distribution of the TR disrupting effects exhibit a positive correlation with the industrial layout in the study area. The samples with higher antagonistic activities are located at the industrial production and live- stock raising areas, suggesting that the pollution from industrial activities and livestock raising may be an important source of thy- roid disrupting chemicals. In this study, the bioassay was used to assess the thyroid disrupting effect of soil organic extracts and the characteristics of soil organic extracts from Songhua River basin in Jilin City were determined, which is useful for the preven- tion and remediation of soil pollution and provides basic toxicity information in soil risk assessment.