Isnard P
Rhône-Poulenc Industrialisation, Decines, France.
Ecotoxicol Environ Saf. 1998 May-Jun;40(1-2):88-93. doi: 10.1006/eesa.1998.1647.
The conventional approach for assessing the environmental impact of wastewaters uses a set of global physicochemical and ecotoxicological parameters and is well adapted to the vast majority of wastewaters. When some chemicals may be particularly harmful for the environment, a specific approach based on a comparison between the predicted environmental concentration (PEC) and the predicted no-effect concentration (PNEC) may be used. The four steps of extrapolation required for PNEC evaluation are discussed and the importance of the interspecies extrapolation is highlighted. It may also be useful to use an integrated approach relating the characteristics of the wastewater to that of specific compounds. For physicochemical parameters, a simple addition is adequate, whereas, for ecotoxicity, the problem is more complex. The toxicity of a mixture of compounds acting by the same mechanism is often described by the concentration addition model. Although this model is very useful for practical applications owing to its simplicity, a statistical evaluation of its performance indicates that it slightly over-predicts the toxicity of mixtures. A new model derived from the statistically sound "independence action" principle and based on a precise mathematical description of the dose-response relationship is proposed. Applications of this model to mixtures tested with algae demonstrate the accuracy of this model with the experimental data.
评估废水对环境影响的传统方法使用一组全球理化和生态毒理学参数，并且非常适用于绝大多数废水。当某些化学物质可能对环境特别有害时，可以采用基于预测环境浓度（PEC）与预测无效应浓度（PNEC）比较的特定方法。讨论了PNEC评估所需的四个外推步骤，并强调了种间外推的重要性。使用将废水特性与特定化合物特性相关联的综合方法也可能是有用的。对于理化参数，简单相加就足够了，而对于生态毒性，问题则更为复杂。通过相同机制起作用的化合物混合物的毒性通常用浓度相加模型来描述。尽管该模型因其简单性在实际应用中非常有用，但其性能的统计评估表明它略微高估了混合物的毒性。提出了一种基于统计合理的“独立作用”原理并基于剂量-反应关系的精确数学描述的新模型。该模型在藻类测试混合物中的应用证明了该模型与实验数据的准确性。
