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Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Ecotoxicological information

Long-term toxicity to fish

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Administrative data

Link to relevant study record(s)

Description of key information

Key value for chemical safety assessment

Additional information

Due to the rapid hydrolysis of the substance, the chemical safely assessment is based on the silanol hydrolysis product propylsilanetriol.

Testing for long-term toxicity to fish is not considered necessary because:

  • The substance is used under highly controlled conditions and, therefore, aquatic exposure is low.


  • The substance is highly water-soluble, has low bioavailability (based on log Kow <3 (-1.4)) and there is no reason to expect any specific mechanism of toxicity beyond narcosis. Therefore, the occurrence of toxic effects that were not expressed in the existing short-term aquatic studies, read across from a structural analogue with the same silanol hydrolysis product, would be considered unlikely.


  • Long-term testing has been carried out with Daphnia at high concentrations up to 100 mg/l (read-across from a structural analogue). No effects were observed. An algal NOEC of ≥913 mg/l has also been determined. The registration substance and the substances used for read-across are part of a class of low functionality compounds acting via a non-polar narcosis mechanism of toxicity, and as such log Kow drives toxicity. It is therefore expected that fish will not be any more sensitive than invertebrates or algae. As no long-term toxic effects were expressed in these organisms, a long-term fish toxicity test is not necessary.

Aquatic PNECs have not been derived due to the high water solubility and low log Kow of the registration substance, and absence of effects when structural analogues have been tested at high concentrations. Overall it is concluded that no hazard is identified and therefore further in vivo testing is not considered necessary or justified on ethical grounds.


Details on PNEC derivation and risk can be found in IUCLID Section 6.0 and Chapters 9 and 10 of the Chemical Safety Report, respectively.