Registration Dossier

Ecotoxicological information

Long-term toxicity to fish

Currently viewing:

Administrative data

Link to relevant study record(s)

fish early-life stage toxicity
Data waiving:
study scientifically not necessary / other information available
Justification for data waiving:

Description of key information

Key value for chemical safety assessment

Additional information

No long-term toxicity to fish data are available with 3-trimethoxysilylpropyl methacrylate (CAS 2530-85-0).

Due to the rapid hydrolysis of the substance, the chemical safely assessment is based on the silanol hydrolysis product 3-(trihydroxysilyl)propyl methacrylate.

In accordance with REACH Annex XI, there is no need to further investigate the effects of this substance in a long-term toxicity to fish study because there are sufficient data to derive a classification and qualitative risk assessment based on the available data. The qualitative chemical safety assessment is based on the silanol hydrolysis product 3-(trihydroxysilyl)propyl methacrylate, which has the following properties:

  • highly water-soluble (>10^6 mg/l)
  • low bioavailability (based on log Kow -0.9).
  • several short-term aquatic toxicity studies are available indicating no effects up to 1000 mg/l except for an algal NOEC of 322 mg/l when expressed in terms of the silanol hydrolysis product.

Based on the short-term aquatic data set, the most sensitive trophic level is algae, which is also considered a long-term study for the endpoint.

The substance contains two structural alerts:Michael type addition and a,ß-unsaturated carbonyl, which are structural alerts for fish and invertebrates, respectively (ECHA 2008, R.10, Table R.10-16). The data in the OECD SIDS Initial Assessment Profile (2004) on methacrylate esters indicates thatesters are of low to high toxicity to aquatic organisms and that toxicity increases with increasing lipophilicity and molecular size, as would be expected for a non-polar rather than a specific mode of action.

In addition, there is very limited evidence of hydrolysis of the methacrylate group and it is unlikely that methacrylic acid is formed.

Therefore, the substance is not considered to have a specific mode of action.

The occurrence of toxic effects that were not expressed in the existing short-term aquatic studies would be considered unlikely.

Overall it is concluded that the chemical safety assessment does not indicate the need for further in vivo testing, which would furthermore not bejustified on ethical grounds.


Refer to the discussion in the Section 6 endpoint summary (Section 7.0 of CSR) for further discussion of the approach to chemical safety assessment for the registered substance.


ECHA (2008) Guidance on the information requirements and chemical safety assessment. Chapter R.10: Characterisation of dose [concentration]-response for environment. May 2008.

OECD (2004) SIDS Initial Assessment Profile (2004) SIAM 18, 20 -23 April 2004, US+JP/ICCA. Methacrylate Esters.