Registration Dossier

Diss Factsheets

Ecotoxicological information

Toxicity to aquatic algae and cyanobacteria

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

The following study has been submitted to address the toxicity to algae and cyanobacteria endpoint:
Steger-Hartmann T (1999). Growth inhibition test of di-n-butyltin oxide (ZK 26385) on the green algae Scenedesmus subspicatus. Testing laboratory: Schering AG, Experimentelle Toxikologie, D-13342 Berlin, Germany. Report no.: IC28. Owner company: Schering AG, Experimentelle Toxikologie, Berlin, Germany. Study number: TXST19980234. Report date: 1999-02-17.
The Steger-Hartmann and Wendt study, as a stand alone study it is a relaibility 1, however as it is used for read-across purposes, the study has been assigned a reliability 2 (reliable with restrictions). The data presented is on the substance dibutyltin oxide.

Key value for chemical safety assessment

EC50 for freshwater algae:
1.6 mg/L

Additional information

The EC50 (72 h) for biomass and growth rate was determined to be = 1.6 mg/l. DBTO had an inhibitory effect on the growth of algae at all concentrations, observable after 24 hours. However, there was no concentration dependence and it did not exceed 40% and 20% for biomass and growth rate respectively, even after 72 hours. Therefore the observed effects were regarded as not substance-related.

Read-across from dibutyltin oxide to dibutyl dimethoxystannane concerning aquatic toxicity endpoints was considered appropriate as dibutyltin and octyltins are known to hydrolyse rapidly in water (as presented by Yoder 2003, under the data requirement hydrolysis), and form, in the case of dibutyltins, dibutyltin oxide.