Registration Dossier

Ecotoxicological information

Toxicity to microorganisms

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

The study by Geerts (2010) is considered key due to the GLP guideline study wrt active sludge respiration inhibition, 3h duration. The NOEC was detemined >= 640 mg/L for EDTA-MnNa2. This would correspond to >= 654 mg/L EDTA-CuNa2.

Key value for chemical safety assessment

Additional information

To investigate toxicity to microorganisms from different sources, multiple endpoints have been investigated with several EDTA salts or complexes. Respiration rate, bioluminescense, nitrification inhibition and growth of Pseudomonas have been investigated, but not all studies are equally reliable.

Geerts (2010) is preferred, supported by Hu (2003), BASF (1988) & van Ginkel (2000) all indicating that effects of the EDTA salts or complexes are not harmful to activated sludge.

To determine a PNEC for microorg the study by Hu (nitrification inhibition) should also be considered as this endpoint is generally considered more sensitive than sludge respiration. The EC50 endpoint was determined at 2.4 mmol/L for EDTA-H4 (701 mg/L) corresponding to 953 mg/L EDTA-CuNa2.