Registration Dossier
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EC number: 204-254-5 | CAS number: 118-47-8
Toxicity to aquatic algae and cyanobacteria
Administrative data
Link to relevant study record(s)
Description of key information
Based on the QSAR prediction done using the EPI Suite ECOSAR version 1.10 (EPI suite, 2016), the 96 hours EC50 was estimated to be 44420.914 mg/l on green algae for substance Pyrazolone T with growth inhibition effects. Thus based on this value, it can be concluded that the substance can be considered as non-toxic to aquatic organisms and thus can be classified as not hazardous as per the CLP criteria.
Key value for chemical safety assessment
- EC50 for freshwater algae:
- 44 420.914 mg/L
Additional information
Various predicted data for the target chemical Pyrazolone T (CAS No. 118-47-8) were reviewed to summarize the following information:
Based on the QSAR prediction done using the EPI Suite ECOSAR version 1.10 (EPI suite, 2016), the 96 hours EC50 was estimated to be 44420.914 mg/l on green algae for substance Pyrazolone T with growth inhibition effects. Thus based on this value, it can be concluded that the substance can be considered as non-toxic to aquatic organisms and thus can be classified as not hazardous as per the CLP criteria.
72 hrs aquatic toxicity study was predicted (SSS QSAR Prediction model, 2016) to assess toxic effects of the test compound Pyrazolone T (CAS No. 118-47-8) and the results were predicted. The study was based on the effects of the test compound on Desmodesmus subspicatus in a static fresh water system. The predicted data suggests the effective concentration (EC50) for the test compound Pyrazolone T (CAS No. 118-47-8) was estimated to be49.874 mg/l on the basis of growth rate. Thus based on this value, it can be concluded that the substance can be classified as aquatic chronic category 3. Since the partition coefficient of the test chemical is not≥ 4 (i.e, log Kow = -1.0), test chemical Pyrazolone T can be considered as non-toxic to aquatic organisms and thus cannot be classified as hazardous as per the CLP criteria.
Estimated 72 hrs EC50 value of test substance Pyrazolone T on Pseudokirchneriella subcapitata was determined (Danish QSAR database, 2016) by three different models i.e, Battery, Leadscope and SciQSAR used within Danish QSAR database. Based on inhibition in growth rate of test organism Pseudokirchneriella subcapitata, the estimated 72 hrs EC50 value was found to be 319.2977 mg/l. Thus based on this value, it can be concluded that the substance can be considered as non-toxic to aquatic organisms and thus cannot be classified as hazardous as per the CLP criteria.
Based on the overall reported results of various predicted data for target substance, it can be concluded that the substance can be classified as not hazardous as per the CLP criteria.
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