Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

The substance Reaction mass of N,N'-ethane-1,2-diylbis(12-hydroxyoctadecanamide), N,N'-hexane-1,6-diylbis(12-hydroxyoctadecanamide) and N,N'-[1,3-phenylenebis(methylene)]bis(12-hydroxyoctadecanamide) consists of three structurally similar bisamides: N,N'-ethane-1,2-diylbis(12-hydroxyoctadecanamide), N,N'-hexane-1,6-diylbis(12-hydroxyoctadecanamide) and N,N'-[1,3-phenylenebis(methylene)]bis(12-hydroxyoctadecanamide). Experimental data on this substance are not available. The individual constituents and mixtures of them and similar amides are considered suitable read-across substances.

The short-term toxicity for fish is assessed in guideline studies for the read-across substances 1,3-bis[12-hydroxy-octadecamide-N-methylene]-benzene and 12-hydroxyoctadecanoic acid, reaction products with 1,3-benzenedimethanamine and hexamethylenediamine. For 1,3-bis[12-hydroxy-octadecamide-N-methylene]-benzene, a guideline study according to EU Method C.1 was carried out using carp. For 12-hydroxyoctadecanoic acid, reaction products with 1,3-benzenedimethanamine and hexamethylenediamine a guideline study was carried out according to EU Method C.1 using Oncorhynchus mykiss. For both read-across substances, the LC50 (96 h) was determined to be greater than the limit of solubility.

The short-term toxicity for aquatic invertebrates is assessed in guideline studies for the read-across substances 1,3-bis[12-hydroxy-octadecamide-N-methylene]-benzene and 12-hydroxyoctadecanoic acid, reaction products with 1,3-benzenedimethanamine and hexamethylenediamine. For both read-across substances, no EC50 or NOEC values could be determined, respectively, because the water solubility of the test material was too low.

In guideline studies on the short-term toxicity for aquatic algae for two read-across substances, no toxicity was observed. Saturated solutions of 12-hydroxyoctadecanoic acid, reaction products with 1,3-benzenedimethanamine and hexamethylenediamine did not show adverse effects on Selenastrum capricornutum because the solubility of the test material was too low. In dispersions of 1,3-bis[12-hydroxy-octadecamide-N-methylene]-benzene slight growth inhibition of Pseudokirchneriella subcapitata was observed which was not related to toxicity but physical effects of the dispersed test material particles.

The experimental data on fish, aquatic invertebrates and algae are supported by the estimated toxicity values for the three individual constituents of the substance being registered, which were calculated by the QSAR software EPI Suite, ECOSAR v1.11 (used models: ECOSAR class Amides and Neutral Organic Structure Activity Relationship). For all constituents, the predicted values – LC50 (96h, fish), EC50 (48h, daphnids) and EC50 (96h, algae) - result in values higher than the water solubility. Therefore, no effects at saturation are expected.

For the toxicity to microorganisms, a guideline study on the read-across substance 1,3-bis[12-hydroxy-octadecamide-N-methylene]-benzene is provided, which shows no significant inhibition in the respiration rate of sludge at 100 mg/l of the test material.

Based on the experimental results on the read-across substances and the toxicity predictions for individual constituents by EPI Suite, the properties of the multi-constituent substance are expected to be comparable. Experiments on the aquatic toxicity are considered technically not feasible due to the low water solubility and no study was conducted. The CLP criteria for classification as hazardous to the aquatic environment, Acute 1 or Chronic 1 to 3 are not met.

However, according to the experimental data on the read-across substances and the toxicity predictions for individual constituents, the substance being registered is poorly soluble in water, not rapidly biodegradable and has a log Kow ≥ 4, indicating a potential to bioaccumulate. Thereby, the CLP criteria for the “safety net” classification as hazardous to the aquatic environment, Chronic 4 are met. Consequently, the substance is classified as Aquatic Chronic category 4.

Additional information

The toxicity values for the individual constituents were additionally calculated by ChemProp. These values are disregarded for assessment, because the constituents were out of the applicability domains of the used models.