The KAshinhou Tool for Ecotoxicity (KATE) system, including ecotoxicity quantitative structure–activity relationship (QSAR) models, was developed by the Japanese National Institute for Environmental Studies (NIES) using the database of aquatic toxicity results gathered by the Japanese Ministry of the Environment and the US EPA fathead minnow database. In this system chemicals can be entered according to their one-dimensional structures and classified by substructure. The QSAR equations for predicting the toxicity of a chemical compound assume a linear correlation between its log P value and its aquatic toxicity. KATE uses a structural domain called C-judgement, defined by the substructures of specified functional groups in the QSAR models. Internal validation by the leave-one-out method confirms that the QSAR equations, with r2>0.7, RMSE ≤0.5, and n>5, give acceptable q2 values. Such external validation indicates that a group of chemicals with an in-domain of KATE C-judgements exhibits a lower root mean square error (RMSE). These findings demonstrate that the KATE system has the potential to enable chemicals to be categorised as potential hazards.

SynopsisThe polymerization of picryl (PMA), 2,Pdinitrophenyl (P,PDNMA), 2,Gdinitrophenyl (2,s-DNMA), 2-methyl-4,6-dinitrophenyl (MDNMA), and 2,6dimethylphenyl methacrylates (DMMA) w&s carried out in benzene at 60°C. PMA, 2,6-DNMA, and MDNMA did not undergo radical homopolymerization, while 2,4-DNMA and DMMA did. The results suggest that the growing radical readily attacks the oxygen atom of the nitro group at the 2 position of the terminal phenyl group due to the steric effect of the substituent a t the 6 position, resulting in chain termination. PMA formed a charge-transfer complex with Snaphthyl methacrylate (NMA). The stoichiometric composition of this complex was shown to be 1 : 1 molar complex. PMA was readily copolymerized with NMA. The amount of solvent affected the composition of the copolymer obtained a t a given same mole fraction in feed. The results suggest that charge-transfer interaction between the ester groups affects the copolymerization mechanism.. 707

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