Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Ecotoxicological information

Toxicity to aquatic algae and cyanobacteria

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

In this study Octopirox-Fe(III)-complex was found to inhibit the growth of the freshwater green alga Desmodesmus subspicatus after 72 h with the following effect values (geometric mean measured test item concentrations): The EC50-values with 95 % confidence intervals for inhibition of specific growth rate (ErC50) and yield (EyC50) after 72 h were 10.8 (9.62 – 12.4) and 6.71 (6.07 – 7.43) mg/L, respectively.

The test effect was observed to be reversible at all tested concentrations following 72 h exposure and 4 - 8 days of growth under test conditions.

All effect levels are given based on geometric mean measured concentrations of Octopirox-Fe(III)-complex.

Key value for chemical safety assessment

EC50 for freshwater algae:
10.8 mg/L
EC10 or NOEC for freshwater algae:
6.3 mg/L

Additional information

Octopirox forms chelate complex with two and three valent ions like Fe(II), Fe(III), Al(III). If the test organism is dependent from such ions during the test e.g. algae, daphnia, this will influence growth and survival. As these ions mentioned before are ubiquitous in the sewer, the sewage treatment plant and in the environment e.g. river Octopirox forms immediately these chelate complexes. In order to avoid interference with the necessary test conditions in the Guideline tests and to avoid unrealistic test test settings e.g. pronounced toxicity by interference with essential ions, the aquatic ecotoxicity tests were carried out in river water where the ions mentioned above are present. For algae the Octopirox Fe(III) complex had to be tested as otherwise the required growth rate for the test according OECD 201 could not be achieved.