Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

Alkyl amidoamine/imidazolines are mainly protonated under environmental conditions. This means that the protonated fraction will behave as salt in water and will have a very low vapour pressure. A vapour pressure of 0.000079 and 0.000039 mPa were measured for respectivily the DETA and PEPA based imidazoline at 20 °C. The solubility of this cationic surface active substance will be influenced by the pH and is difficult to determine because of the surface active properties. As an alternative as suggested by the REACH guidance R.7 the CMC at pH 7 and 23°C was determined.

The solubility in the form of CMC was measured for three types of Imidazolines, i.e. the DETA, TEPA and PEPA based imidazolines.

Evaporation from water is based on the low vapour pressure and the observed CMC values very unlikely. The actual dissolved concentration in water will be extremely low as alkyl amidoamines/imidazolines will sorb strongly to sorbents both based on hydrophobicity and ionic interaction where the ionic interaction will govern the partitioning process. Two refined sorption/desorption tests were performed for the resp. DETA and PEPA based imidazoline and for both identical sorption was observed. For silt soil a Kd of 47249 L/kg was observed indicating that once sorbed the substance has a low leaching potential. For risk assessment purposes Kd was recalculated to a Koc of 944980 L/kg despite the fact that there is no direct relationship between the sorption and organic matter content of a sorbent.