Aniline, Phenol Compounds The Joint Toxicity Of Luminescent Bacteria

The single toxicity of 9 anilines and 12 pheonols to photobacterium phosphoreum were determined respectively. On the basis of single toxicity, the joint toxicity of binary mixtures of aniline and substituted anilines, phenol and substituted phenols in the toxic unit ratios of 1:1,1:4,4:1 were measured and 15min-EC50 values were determined.Toxic Unit(TU), Additive Index(AI), Mixture Toxicity Index(MTI) and Isobole plot were used to evaluate the joint toxicity of aniline and substituted anilines. The result showed that the types and magnitudes of joint actions of binary mixtures of aniline and substituted anilines at different solution compositions were different; meanwhile, even at the same solution composition, the evaluating methods also influence the results. In general, most binary mixtures showed additivity with the overlaps of their confidence belts and the additivity index.Toxic Unit(TU), Additive Index(AI), Mixture Toxicity Index(MTI) and similar parameter(x) were used to evaluate the joint toxicity of phenol and substituted phenols. The results indicated that the majority of joint actions of binary mixtures of phenols and substituted phenols were mainly additivity, only a few ones showed weak synergism or weak antagonism with their evaluating values falling outside the limits of additivity.8 structure parameters and 5 physicochemical parameters of anilines and phenols were calculated using the computer softwares. The Quantitative Structure-Activity Relationship was built between the single toxicity values of anilines or phenols and their parameters, for anilines : -lgEC50=2.951-0.0564 Hf+0.300 u; for phenols:-lgEC50=6.158-0.279pKa. The substituted anilines toxicity values and substituted phenols toxicity values in the binary mixtures were predicted respectively using the QSAR equations and additivity model. Good agreement between thepredicted and measured values was found. Therefore, the QSAR equationscould be used to predict the mixture toxicity if the joint action mainlyshowed additivity.