Registration Dossier

Ecotoxicological information

Toxicity to aquatic algae and cyanobacteria

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

(72-h) ErC50: 931 mg/l inhibition of growth rate Desmodesmus subspicatus (read-across from CAS 4420-74-0) ErC10 92 mg/l inhibition of growth rate NOECR: 40 mg/l inhibition of growth rate Desmodesmus subspicatus (read-across from CAS 4420-74-0)

A stepwise testing strategy is proposed to address the requirements of the ECHA draft decision. Please refer to the attachment in Section 13. This read-across is retained as an interim measure to calculate a PNEC and support the existing chemical safety assessment until new evidence becomes available.

Key value for chemical safety assessment

EC50 for freshwater algae:
931 mg/L
EC10 or NOEC for freshwater algae:
40 mg/L

Additional information

There are no data for the registered substance. However a 72-h EC50 value of 931 mg/l and a NOEC of 40 mg/l have been determined for the effects of structurally analogous substance, 3-trimethoxysilylpropane-1-thiol (CAS 4420-74-0), on growth rate of Desmodesmus subspicatus (tested as Scenedesmus subspicatus) based on nominal concentrations of the substance, according to EU C.3. The test substance is susceptible to very rapid hydrolysis and it is therefore likely that, under the conditions of the study, the test organisms were primarily exposed to the hydrolysis products of the substance.

Although this value is above the water solubility of the parent registered substance, the read-across is considered valid as the exposure was related to the hydrolysis product.