Registration Dossier

Diss Factsheets

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Additional information

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 growth inhibition study on the algae Pseudokirchneriella subcapitata was performed on the registered substance. In this study, the 72h-ErC50 value for growth rate, based on geometric mean measured concentrations, was determined to be 169.4 mg/L (95%-Confidence Limit: 147.3 – 193.2 mg/L). This study was supported by a conservative QSAR result on algae performed on the registered substance also.

The QSAR predictions (iSafeRat holistic approach v1.5) have 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 growth inhibition of algae and immobilisation of daphnids were determined using a validated QSAR for the Mode of Action in question (ester) using training sets for which the concentrations of the test substance had been determined by chemical analyses over the test period. The 72h-ErC50 value based on growth rate of algae was determined to be 81 mg/L (95% CL: 29 - 221 mg/L). This predicted toxicity value was found to be comparable and more conservative than the in vivo result at 169.4 mg/L. For the short-term toxicity to aquatic invertebrates endpoint, the iSafeRat QSAR model was validated for use with the same applicability domain and under the same conditions as the algae QSAR using a holistic approach. Thus, the prediction method can be considered sufficient to assess, in a conservative way, the toxicity of the registered substance to daphnid. The 48h-EC50 value based on mobility was determined to be 368 mg/L (95%-CL: 139 - 972 mg/L). An in vivo acute daphnia study is therefore not considered necessary.