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Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Additional information

Short-term studies from three different trophic levels (algae, daphnia, fish) are available for Y-15099 (CAS 220727-26-4). In all studies, a filtered test solution of nominal 100 mg/L was used for testing. Since Y-15099 is hydrolytically unstable at environmentally relevant pH levels, this test solution mainly reflects the hydrolysis products ethanol, octanoic acid and silanetriol, (3-mercaptopropyl)-. No effects were observed under conditions tested resulting in a NOEC = 100 mg/L and/or E(L)C50 > 100 mg/L. The results are expressed relative to the nominal concentration. Corresponding measured concentration for the substance in the treated test medium over the course of the studies was 0.017 - 0.046 mg/L. In the algae study, analysis of the test media showed that the measured concentration of the parent substance declined to below the LOQ. Therefore, it can be concluded that the studies were primary performed with the hydrolysis products as recommended by the ECHA, 2008 (“Guidance on information requirements and chemical safety assessment: Chapter R.7b: Endpoint specific guidance”).

Testing with microorganisms up to a nominal concentration of 1000 mg/L resulted in a NOEC of 320 mg/L. The respiration rate was slightly inhibited at a test concentration of 1000 mg/L (23%). Thus, inhibition of the degradation process in sewage treatment plants caused by the test substance and its hydrolytic degradation products is not expected.

Long-term toxicity testing with fish and aquatic invertebrates was not performed since the environmental exposure assessment for Y-15099 indicates no risk for the aquatic compartment (all RCR < 1). Thus, a long-term term toxicity testing is not necessary according to Section 3.1, Annex XI of Regulation (EC) 1907/2006.