2-aminoethyldiethylamine

Toxicity to aquatic algae and cyanobacteria

Description of key information

Acutely harmful to aquatic algae.

Key value for chemical safety assessment

EC50 for freshwater algae:

34 mg/L

EC10 or NOEC for freshwater algae:

26 mg/L

Additional information

In a key static growth inhibition test, the fresh algae Pseudokirchnerella subcapitata was exposed to the read-across substance 3 -aminopropyldiethylamine (CAS 104 -78 -9) for 72 hours according to the OECD guideline 201 and under GLP conditions. The algae were exposed to the following nominal concentrations: 0, 4.77, 7.63, 12.21, 19.53, 31.25 and 50 mg/L. The final concentrations of the read-across substance 3 -aminopropyldiethylamine were maintained within the designated limit of 80% of the initial concentrations in non-inoculated flasks. Therefore, the effect concentrations and NOEC have been calculated using the nominal concentrations. The 72 -h ErC50 and the 72 -h NOEC were determined to be 34 and 19.53 mg/L, respectively. The 72 -h ErC10 was determined to be 26 mg/L (Arkema 2000, report no.: 57/99/A). The test solutions were not neutralised. They were in acceptable range of 7.6 to 9.3 at the beginning of the test and 8.0 to 9.4 after 72 hours of exposure. Therefore, an effect of the pH level on the toxicity of the test substance can be excluded. The validity criteria of the study were fulfilled.

 

As a supportive study, acute toxicity to Desmodesmus subspicatus was investigated according to German Industrial Standard DIN 38 412/9. The 72-h EC50 was determined to be between 100 and 150 mg/L (BASF AG 1990, report no.: 02/90/134). The concentrations were not measured in the vessels during the test but the read-across substance 3 -aminopropyldiethylamine (CAS 104 -78 -9) is expected to be stable in water as shown in the key study. Moreover, the read-across substance 3 -aminopropyldiethylamine is miscible in water, it has a low Henry's Law constant and a low adsorption potential (log Kow and log Koc < 3). Therefore there is no cause of significant deviation from nominal to real substance concentrations. The samples were not neutralised. They were in acceptable range of 7.6 to 9.3 at the beginning of the test and 8.0 to 9.4 after 72 hours of exposure. Therefore, an effect of the pH level on the toxicity of the test substance can be excluded.

Another test was conducted according to German Industrial Standard DIN 38 412/9. But the stock solution of the read-across substance 3 -aminopropyldiethylamine was neutralised with 1N HCl to pH 7. In this study, the 72 -h ErC10 and the 72 -h ErC50 were determined to be 3.45 g/L and 7.12 g/L, respectively (BASF AG 1990, report no.: 02/90/134).

In conclusion, 2 -aminoethyldiethylamine is expected to be acutely harmful to aquatic algae.