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Ecotoxicological information

Endpoint summary

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Additional information

No data are available for dichloro(dimethyl)silane. Reliable acute aquatic toxicity tests results are however available from a read-across substance (Dimethylsilanediol; CAS No. 1066-42-8) for freshwater fish (Oncorhynchus mykiss), invertebrates (Daphnia magna) and algae (Pseudokirchneriella subcapitata). LC50 or EC50 values for the three organisms were >126, >117 and >118 mg/L respectively. A NOEC of 118 mg/L was determined in the algal test.

No reliable experimental test results are available for long-term toxicity of dichloro(dimethyl)silane to invertebrates. However, a read-across 21-day NOEC of 100 mg/l has been determined for the effects of structurally-similar substance, trichloro(ethyl)silane (CAS 115 -21 -9), on survival and reproduction of Daphnia magna.

Testing for long-term toxicity to fish is waived in accordance with Column 2 of REACH Annex IX as the chemical safety assessment indicates that it is not necessary:

- The substance hydrolyses very rapidly (half-life <<1 min at pH 7 and 25°C) and the acute toxicity of the silanol hydrolysis product is low.

- The substance is used under highly controlled conditions and, therefore, exposure of the aquatic environment is low (see Section 9 for further details).

An activated sludge respiration inhibition 3hr EC10 value of >100 mg/l (loading rate) was determined for a structurally-related substance (trimethoxy(methyl)silane CAS 1185 -55 -3) in a reliable study conducted according to an appropriate test protocol, and in compliance with GLP. This data is read-across.