Registration Dossier

Ecotoxicological information

Short-term toxicity to fish

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

(96-h) LC50: 251 mg/l mortality Danio rerio, reliability 1. 

Key value for chemical safety assessment

Additional information

A 96-h LC50 value of 251 mg/l has been determined for the effects of the test substance on mortality of Danio rerio (tested as Brachydanio rerio). An LC0 (NOEC) of 180 mg/l has been determined in the same test. The test was conducted without adjustment of pH and it is possible that effects observed at test concentrations above 180 mg/l may have been the result of low pH. The pH at the 180 mg/L concentration where no effects were observed was never below 5.6. At this concentration mortalities were ≤10%. The results are expressed relative to nominal concentrations.

The test organisms are expected to have been exposed to the hydrolysis products of the substance (acetic acid and ethylsilanetriol) due to the very rapid half-life of the registered substance (<13 s (0.2 min) at pH 4, 7 and 9 and 25°C).

Supporting data are available for a structurally analogous substance trimethoxyvinysilane where a 96 h LC50 value of 191 mg/L has been reported. The QSAR for the silanol hydrolysis product, trimethylsilanol, also indicates the low toxicity of the hydrolysis product (96 h LC50 43 000 mg/l). Both these results support the validity of the study available with triacetoxyethylsilane.