Influence of components structure and composition of binary mixtures of organic compounds on toxicity towards Daphnia Magna

Abstract

Simplex representation of molecular structure is employed for consensus QSAR analysis of toxicity towards Daphnia magna of sodium salts of α-alkoxycarbonylsulfuric acids, aliphatic n-alcohols, phenols and their binary mixtures. The structure of a mixture is represented both using descriptors of individual compounds included in the mixture and using novel specific mixture parameters termed unconnected simplexes. The studied dataset included 15 single compounds and 20 mixtures. The logarithm of EC50 (mmole/l) is used as a target function. Aims of the research are the determination of molecular fragments with positive or negative influence on the toxicity and developing QSAR models capable to predict properly the toxicity of new compounds and mixtures from their structure and composition. Successful consensus model based on forty best QSAR models (R2=0,86…0,97; Q2=0,74…0,96; R2test=0,86…0,99) is obtained using different training and test sets.

Keywords

• QSAR
• simplex representation of compounds mixtures
• mixture descriptors
• toxicity
• Daphnia magna