Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

- OECD guideline 202 study, short-term toxicity to Daphnia magna (48h), GLP, tested concentrations (nominal): 6.25, 12.5, 25, 50 and 100 mg/L, 100 mg/L revealed 100% immobility/mortality due to pH effects, a neutralized solution containing 100 mg/L 2 -oxoglutarate, EC50 neutralized = >100 mg/l, EC50 not neutralized = 70.7 mg/L.

- OECD guideline 201 study, toxicity to aquatic algae and cyanobacteria, in green alga Pseudokircheriella subcapitata, GLP, geometric mean measured concentrations: 102, 16.7, 1.99, 1.20, 1.32 mg/L, NOEC = 16.7 mg/L, pH-related effects occurred, growth inhibition at 100% after treatment with 102 mg/L 2 -oxoglutaric acid, use of a pH neutralized solution no inhibitory effect at 102 mg/L.

Additional information

The 48-hr-acute toxicity of 2-oxoglutaric acid to Daphnia magna was studied under semi-static conditions according to OECD Guideline 202 (2004).  Daphnids were exposed to control and test chemical at nominal concentrations of 6.25, 12.5, 25.0, 50.0, 100.0 mg a.i./L  in culture medium for 48 h. 100 mg/L 2-oxoglutaric acid resulted in an acidification of the medium to a range of 4.67-4.94 which is far below the acceptable pH range, thus the medium of the group with the highest concentration was once adjusted with 1M NaOH to a pH of 7 and a second vessel was left unadjusted in order to detect any pH related effect. The un-neutralized  100 mg/L group exhibited a mortality of 100% after 48h. In the neutralized high dose group no mortality and immobility occurred. The 48-hour EC50 was 70.7 mg a.i./L (95 % confidence limits: 50.0 – 100.0 mg/L) taken into account the results of the un-neutralized high dose group.

Based on the reliable and relevant data 2 -oxoglutaric acid does not need to be classified according to Regulation (EC) No 1272/2008 (CLP) and the Globally Harmonized Classification and Labeling System (GHS) with respect to toxicity to aquatic algae and cyanobacteria.

In the present study according to OECD Guideline 201 (2011) and GLP compliant, Pseudokirchneriella subcapitata were incubated with the following geometric mean measured concentrations: 102, 16.7, 1.99, 1.20, 1.32 mg/L for 72 h. The growth rate of Pseudokirchneriella subcapitata after incubation with 102 mg/L 2-oxoglutaric acid resulted in 100% inhibition. Therefore, the highest concentration was adjusted to pH 8.1. Under these conditions no cell growth inhibition occurred. The very low pH in the unadjusted test solution was considered to be responsible for the growth inhibition. Under the present conditions the NOEC was determined at 16.7 mg/L.

Based on the reliable and relevant data 2 -oxoglutaric acid does not need to be classified according to Regulation (EC) No 1272/2008 (CLP) and the Globally Harmonized Classification and Labeling System (GHS) with respect to short-term toxicity to aquatic invertebrates.