构建三元混合污染物的三维等效图

Construction of Three-Dimensional Isobologram for Ternary Pollutant Mixtures

等效线分析法广泛应用于二元混合物的毒性相互作用评估.然而,如何构建三维等效图以考察三元混合物中发生的毒性相互作用至今没有文献报道.本研究的主要目的即以三元混合物中3个组分的相对浓度为坐标轴建立三维等效图以考察三元混合物的毒性相互作用.以6种目前在中国广泛使用的农药,包括3种除草剂(2,4-D、敌草净、西草净)和3种杀虫剂(乐果、吡虫啉、残杀威)为混合物组分,采用均匀设计射线法(UD-Ray)分别对三元除草剂和三元杀虫剂混合物中各组分浓度分布进行优化设计,以全面表征实际混合物的浓度多样性.通过费氏弧菌微板毒性分析法测定农药及其三元混合物在不同浓度下的发光抑制毒性,以浓度加和(CA)模型为加和参考模型,建立三维等效图,分析各混合物的毒性相互作用.结果表明,三维等效图能清晰、直观地反映三元混合物的毒性相互作用信息,开拓等效分析法在三元混合物毒性分析中的应用.

Isobolographic analysis was widely used in the interaction assessment of binary mixtures. However,how to construct a threedimensional( 3D) isobologram for the assessment of toxicity interaction within ternary mixtures is still not reported up to date. The main purpose of this paper is to develop a 3D isobologram where the relative concentrations of three components are acted as three coordinate axes in 3D space to examine the toxicity interaction within ternary mixtures. Taking six commonly used pesticides in China,including three herbicides( 2,4-D,desmetryne and simetryn) and three insecticides( dimethoate,imidacloprid and propoxur) as the mixture components,the uniform design ray procedure( UD-Ray) was used to rationally design the concentration composition of various components in the ternary mixtures so that effectively and comprehensively reflected the variety of actual environmental concentrations.The luminescent inhibition toxicities of single pesticides and their ternary mixtures to Vibrio fischeri at various concentration levels were determined by the microplate toxicity analysis. Selecting concentration addition( CA) as the addition reference,3D isobolograms were constructed to study the toxicity interactions of various ternary mixtures. The results showed that the 3D isobologram could clearly and directly exhibit the toxicity interactions of ternary mixtures,and extend the use of isobolographic analysis into the ternary mixtures.