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One experimental study of reliability 1 (based on international guideline and GLP compliance) and two QSAR results are available to assess the aquatic toxicity of the registered substance, on aquatic invertebrates and algae.

The experimental short-term toxicity study on the aquatic invertebrate, Daphnia magna, was performed on an analogue substance. This substance,

a mixture of the same stereoisomers present in the registered substance except that the ratio is inversed, is considered adequate for read-across purposes. In this study the 48h-EC50 value, based on the mean measured concentration, was determined to be 20.3 mg/L (95%-Confidence Limit: 16.0 - 25.6 mg/L). This study was supported by a QSAR result on aquatic invertebrates performed on the registered substance.

The QSAR predictions (iSafeRat holistic approach v1.3) has been validated to be compliant with the OECD recommendations for QSAR modeling (OECD, 2004) and predict the ecotoxicological values which would be expected when testing the substance under experimental conditions in a laboratory following OECD Guidelines. The immobility of the daphnids was determined using a validated QSAR for the Mode of Action in question, (MOA 1, non-polar narcosis) using training sets for which the concentrations of the test substance had been determined by chemical analyses over the test period. The 48h-EC50 value based on mobility of aquatic invertebrates was determined to be 15.4 mg/L (95%-Confidence Limit: 14.09 - 16.87 mg/L). Based on this data, the QSAR result obtained on the aquatic invertebrates supports the experimental study and can be considered conservative. The iSafeRat QSAR model was validated for use with the same applicability domain and under the same conditions as the daphnid QSAR and as the 48 h daphnid immobilisation result is similar to that of the QSAR prediction; this provides further evidence that the prediction method can be considered sufficient to assess the toxicity of the registered substance to algae. The 72h-EC50 based on growth rate of algae was determined to be 14.6 mg/L (95%-Confidence Limit: 12.91 - 16.61 mg/L). An in vivo algae study is not considered necessary.