Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Additional information

Toxicity to fish

The substance was tested for its acute toxicity to the rainbow trout over a period of 96 hours in a static system. The study was performed according to the OECD Guideline No. 203 and the EEC Directive 92/69 Part C.1.

Based on the results of a range-finding test performed with test article concentrations of 100, 10 and 1.0 mg/l in a static system, a limit test was performed at a test article concentration of 100 mg/l in order to demonstrate that the LC50 is greater than this concentration. Untreated test medium was run in addition to the 100 mg/l test concentration as a control.

The 100 mg/l test concentration and the control were verified analytically by HPLC at the beginning and at the end of the limit test. Measured test article concentrations were 99.4 % of nominal at hour 0 and 97.6 % of nominal after 96 hours of exposure. Consequently, the biological data are expressed as nominal concentrations.

At the 100 mg/l test article concentration, as well as in the control no mortality of fish occurred during the 96-hour exposure period, and no sublethal effects were observed over the 96-hour exposure period. Therefore, the NOEC and LC0 were determined to be ≥ 100 mg/l, and the LOEC, LC50 and LC100 were determined to be >100 mg/l.

Toxicity to daphnia

No immobility was observed in the 6.25, 12.5, 25 and 50 mg/l test concentrations over the 48-hour exposure period. In the 100 mg/l test concentration, no immobility was observed after 24 hours of exposure, and 25 % immobility was observed after 48 hours of exposure.

Based on these results after 24 hours of exposure, the EC0 (NOEC) is ≥100 mg/l and the LOEC, EC50 and EC100 are >100 mg/l. After 48 hours of exposure, the EC0 (NOEC) is 50 mg/l, the LOEC is 100 mg/l, and the EC50 and EC100 are >100 mg/l.

Toxicity to algae

In conclusion, this modified algal test has clearly demonstrated that the observed growth inhibition effect of the test item on Pseudokirchneriella subcapitata was caused only by an indirect effect, the light filter effect in the colored test solutions. Thus, a toxic effect of the test item on the algal cells can be excluded up to the highest test concentration of 100 mg/l. For this substance, the following values considering the growth rate were determined: EC50 (72 h) > 100 mg/L and NOEC (72 h) = 3.2 mg/L. The second test with Scenedesmus subspicatus the EC50 (72 h) is 12.5 mg/L based on biomass and 66.5 mg/L based on growth rate.

Toxicity to mircoorganisms

The EC50 (30 minutes) of the substance was determined to be >100 mg/L.