Institute of Ecological Science, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands.
Chemosphere. 2010 May;79(9):953-7. doi: 10.1016/j.chemosphere.2010.02.032. Epub 2010 Mar 23.
Two reference models are commonly used to predict mixture toxicity, Concentration Addition and Independent Action. For accurately predicting mixture effects, both reference models need a full description of the dose-response curve for all single chemicals present in the mixture. We studied the mixture effect of nickel and chlorpyrifos on survival of the soil-dwelling collembolan Folsomia candida exposed for 7weeks in Lufa 2.2 soil. Especially chlorpyrifos toxicity showed extremely steep dose-response curves, making it impossible to fulfil the assumptions required by both reference models. Nevertheless, we showed that by monitoring the development of toxicity in time for both the single compounds and the mixtures it was possible to determine mixture effects. Even at exposure levels below the No Effect Concentration, chlorpyrifos was found to reduce nickel toxicity. In addition, this study clearly showed that toxicity is a dynamic process and that mixture effects may be dependent on exposure time.
两种参考模型通常用于预测混合物毒性，即浓度加和和独立作用。为了准确预测混合物效应，这两种参考模型都需要充分描述混合物中所有单一化学物质的剂量-反应曲线。我们研究了镍和毒死蜱对在 Lufa 2.2 土壤中暴露 7 周的土壤居住跳虫 Folsomia candida 存活率的混合物效应。特别是毒死蜱的毒性表现出极其陡峭的剂量-反应曲线，使得这两种参考模型都无法满足其假设的要求。然而，我们表明，通过及时监测单一化合物和混合物的毒性发展，可以确定混合物效应。即使在低于无效应浓度的暴露水平下，也发现毒死蜱降低了镍的毒性。此外，这项研究还清楚地表明，毒性是一个动态过程，混合物效应可能取决于暴露时间。
