2-dimethylaminoethanol

Toxicity to microorganisms

Description of key information

No information regarding toxicity to microorganisms are available for 2-dimethylaminoethanol.

The key value for chemical safety assessment are taken from the key study of the chemical similar compound 2,2´-(methylimino)diethanol = MDEA (BASF, 1993), whereby the reported EC20 value is set into comparison to a EC50 value regarding a worst-case scenario.

Key value for chemical safety assessment

EC50 for microorganisms:

1 000 mg/L

Additional information

Referring to the toxicity of dimethylaminoethanol towards aquatic microorganisms, no experimental data are available. However, read-across to the substance 2,2´-(methylimino)diethanol (MDEA) was performed due to the structural similarities of both the target and the read-across substance. For the read-across substance, three valid studies are available which are briefly summarised as follows.

 

For the key study, the toxicity of the read-across substance 2,2´-(methyliminio)diethanol (MDEA) towards aquatic microorganisms was investigated similar to OECD Guideline 209 with domestic activated sludge and a total exposure duration of 30 minutes. Nominal substance concentrations of 0 (control) and 1000 mg/L were tested. The substance 3,5 -dichlorophenol in concentrations of 1, 10 and 100 mg/L was used as reference substance with a respiration rate of 20 mg/L*h. As final result, an EC20 greater than 1000 mg/L is reported which is based on the respiration rate. No inhibition on the activated sludge had occurred.

With regard to the supporting study, the toxicity of the read-across substance 2,2´-(methylimino)diethanol (MDEA) was experimentally investigated. Pseudomonas putida was used in a static freshwater test conducted according to DIN 38412, part 8 (BASF AG, 1988). The cultures were exposed to the test substance for 17 hours. Test concentration used were 0 (as control), 15.63, 31.25, 62.5, 125, 250, 500, 1000, and 2000 mg/L. A photometric determination at 436 nm was used to indicate growth inhibition. The results are given as follows: EC10 = 273.8 mg/L, EC50 = 413.8 mg/L, and EC90 = 820.2 mg/L.

Regarding the second supporting study, the toxicity of the read-across substance 2,2´-(methylimino)diethanol (MDEA) towards aquatic microorganisms was tested according to ISO 8192 (BASF AG, 1988). This oxygen consumption inhibition test was performed with activated sludge from BASF wastewater treatment plant and test material concentrations of 0, 100, 500, and 1000 mg/L (2 replicates, respectively). It was a static freshwater test which was performed at 23 °C for a total exposure duration of 30 min. 1000 mg/L was the highest test concentration with less than 20 % respiration inhibition. Therefore, EC20 greater than 1000 mg/L is reported as effect concentration result.