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

This endpoint is covered by a key study (Vryenhoef and Mulee, 2010) performed with zirconium basic carbonate yielding a 72h ErC50 value of > 100 mg/L (nominal) in Desmodesmus subspicatus (OECD TG 201/ EU method C.3).

Key value for chemical safety assessment

Additional information

For toxicity to aquatic algae and cyanobacteria, a single key study is available for zirconium basic carbonate.

This study (Vryenhoef and Mullee, 2010) investigated the effect of zirconium basic carbonate on the growth of Desmodesmus subspicatus over a 72 h period. As zirconium could not be detected (<LOQ) in the test solution, the results were based on nominal concentrations. The ErC50 was >100 mg/L and the NOErC was 32 mg/L (based on zirconium basic carbonate). Phosphate monitoring during the test indicated that reduced growth rate was concurrent with phosphate depletion due to phosphate complexing with zirconium and precipitation of the formed complexes. The observed effect is clearly a secondary effect which is not considered environmentally relevant.

In conclusion, zirconium basic carbonate is not expected to be toxic to algae in the natural aquatic environment.