2-ethylhexylamine

Short-term toxicity to aquatic invertebrates

Description of key information

Acutely toxic to aquatic invertebrates.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

2.2 mg/L

Additional information

 The acute toxicity to aquatic invertebrates of 2-ethylhexylamine (CAS 104-75-6) was investigated in two non-GLP tests. Bringmann & Kuehn (1977) performed the test according to a precursor of the German Industrial Standard DIN 38412, part 11. The exposure duration was 24 hours. Based on nominal concentrations, the 24-h EC50 was 2.2 mg/L. The result is supported by a second study of the authors which was performed following the draft of the German Industrial Standard DIN 38412, part 11 (Bringmann & Kuehn, 1982). After 24-h of exposure, the EC50 was 18 mg/L (nominal).

 

According to REACH Guidance R.7b (v2.0, Nov. 2014), 24-h effect values should be considered only in the absence of good quality 48-h values and in conjunction with other available data (e.g non-testing data). As further experimental data are not available to assess the toxicity of the substance to aquatic invertebrates, QSAR models were used to generate 48-h EC50 values. The following results represent effect values from those models where the substance was within the applicability domain. The calculated effect values cover a range between 0.942 to 10.8 mg/L supporting the experimentally determined effect values by Bringmann & Kuehn. Thus, no further experimental data are needed to assess the effects of 2-ethylhexylamine on aquatic invertebrates.

 

ECOSAR v1.11: The acute toxicity was estimated for the chemical class “Aliphatic Amines”. The acute toxicity was calculated using two different sets of user-entered data. In one case, a measured log Kow of 2.82 (see IUCLID Ch. 4.7) was used, while the other calculation is based on an estimated log Kow of 2.73 (see IUCLID Ch. 4.7). In both cases, the water solubility was set to 2500 mg/L (measured, see IUCLID Ch. 4.8). The substance is within the applicability domain of the model for both sets of parameters. The 48-h EC50 was estimated to be 0.942 mg/L using a log Kow of 2.82 and 1.07 mg/L for the lower log Kow of 2.73.

 

Using the QSAR Toolbox v3.83, four regression models were established based on four sets of different referential and parametric boundaries. The substance was within the applicability domain of all four models.The effect values ranged from 2.04 to 8.59 mg/L.

The US EPA T.E.S.T. v4.1 model estimated a 48-h EC50 for Daphnia magna of 10.8 mg/L. The effect value was determined using the consensus method which is formed based on the reasonable results of five submodels. The substance was within the applicability domain of all six models. The confidence in the result of the consensus method is high.