Bis(triethoxysilylpropyl)amine

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

long-term toxicity to aquatic invertebrates

Data waiving:

exposure considerations

Justification for data waiving:

other:

Justification for type of information:

For detailed information on this adaptation based on Annex XI (Section 3), please refer to the CSR attached in Section 13.

Description of key information

A long-term toxicity study on aquatic invertebrates is not necessary as

- exposure considerations in accordance with Annex XI, Section 3, indicate that the exposure of aquatic organisms to 3-(triethoxysilyl)-N-[3-(triethoxysilyl)propyl]-1-propanamine is absent or not significant

and

- the substance has a low hazard potential based on the available toxicity data.

Additional information

In accordance with Annex XI, Section 3, exposure of aquatic organisms to 3-(triethoxysilyl)-N-[3-(triethoxysilyl)propyl]-1-propanamine (CAS No. 13497-18-2) is absent or not significant. 

 

The environmental hazard assessment, PNEC derivation and risk characterization is based on the registered compound itself and its silanol hydrolysis product, 3-(trihydroxysilyl)-N-[3-(hydroxysilyl)propyl]-1-propanamine, as the substance hydrolyses rapidly under environmental conditions (DT50 = 11.9 h at pH 7 and 20 °C). The other hydrolysis product, ethanol, is known for its absence of environmental toxicity (OECD SIDS, 2004) and thus not relevant for the assessment of aquatic toxicity.

 

Short-term aquatic data is available for all three trophic levels (fish, algae, aquatic invertebrates) on the registered compound testing marine species. The hazard assessment showed no short-term aquatic hazard to all three trophic levels (all acute effect values > 100 mg/L). Consequently, no PNECs aqua (freshwater/marine water) were derived. Taking into consideration the fast hydrolysis time of the parent compound and the duration of the acute toxicity tests (48 to 96 h), it can be assumed that the organisms were predominantly exposed to the hydrolysis products. Nevertheless, in the overall ecotoxicological hazard assessment also the effects upon exposure to the parent compound are considered. The registered compound and its silanol hydrolysis product are well soluble. Significant deviations from this overall ecotoxicity profile are not expected and greater long-term toxicity in an additional test with aquatic invertebrates is considered unlikely.

 

However, for the purpose of exposure-based adaptation as in the present endpoint, PNECs were derived in the Chemical Safety Report (CSR, Chapter 9 and 10) for the required risk characterization even though no hazard was identified in the available aquatic toxicity studies. The PNECs aqua (freshwater/marine water) were derived using a worst-case threshold value of 100 mg/L in combination with the standard assessment factors of 1000 and 10000, respectively, as outlined in ECHA guidance R.10 (2008).

 

The risk characterization for registered compound and its silanol hydrolysis product indicated no risk to the aquatic environment (RCR < < 1).

For detailed information on the risk assessment please refer to the attached documentation in Section 13.

 

References:

OECD SIDS, 2004. Ethanol - SIDS Initial Assessment Report For SIAM 19, Berlin, Germany: UNEP Publications.