Registration Dossier

Administrative data

Endpoint:
biodegradation in soil: simulation testing
Data waiving:
study technically not feasible
Justification for data waiving:
other:
Justification for type of information:
Testing for the biodegradation in soil endpoint is waived for the test substance EW-84. Feasibility of laboratory testing has been technically challenging due to the very poor water solubility (0.115 mg/l) of the test and read-across substances. The substance is inherently biodegradable in water (van Ginkel, 2013) based on a GLP compliant OECD Guideline 301D study using the read-across substance octadecanoic acid, 12-hydroxy-, reaction products with ethylenediamine (CAS 100545-48-0). The test substance biodegraded by 22% at day 28 and 37% at day 60 (during the prolonged closed bottle test). Furthermore, a study conducted to increase the availability indicated that the poor water solubility led to slow desorption and dissolution rates of the test substance at high concentrations and was responsible for affecting the biodegradation kinetics. In addition, the study was conducted in river water, which was likely to have had a lower microbial activity than the more usual activated sludge inoculum leading to slower degradation rate. As the test substance is expected to be present in the environment at concentrations in the range of μg/L or lower, faster and more complete degradation may be anticipated under these conditions within a shorter time period (van Ginkel, 2013).

Laboratory studies using the test substance on terrestrial organisms have recently been completed. These include the soil microorganisms nitrogen transformation (OECD 216), earthworm reproduction (OECD 222) and long-term toxicity to terrestrial plants, 6 species (OECD 208). No or low toxicity was reported in these studies with a low potential risk to the terrestrial environment predicted. As confirmed previously, the aquatic toxicity testing carried out to date indicated that the substance is not toxic at the level of solubility.

Further testing on soil biodegradation is waived on the basis of technical feasibility of a study with a very poorly soluble substance and a substance that has not demonstrated toxicity to aquatic and terestrial organisms at its level of solubility. In addition, the results of the aquatic biodegradation test indicated that the substance is inherently biodegradable with the likelihood that degradation would be faster and more complete under sewage treatment work and environmental conditions.

Data source

Materials and methods

Test material

Constituent 1
Chemical structure
Reference substance name:
Reaction mass of N,N’-ethane-1,2-diylbis(12-hydroxyoctadecan-1-amide), Octadecanamide, 12-hydroxy-N-[2-[(1-oxooctadecyl)amino]ethyl]- and Octadecanoic acid, 12-hydroxy-, 1-hexyl-12-[[2-[(12-hydroxy-1-oxooctadecyl)amino]ethyl]amino]-12-oxododecyl ester
EC Number:
701-269-3
Molecular formula:
C38H76N2O4
IUPAC Name:
Reaction mass of N,N’-ethane-1,2-diylbis(12-hydroxyoctadecan-1-amide), Octadecanamide, 12-hydroxy-N-[2-[(1-oxooctadecyl)amino]ethyl]- and Octadecanoic acid, 12-hydroxy-, 1-hexyl-12-[[2-[(12-hydroxy-1-oxooctadecyl)amino]ethyl]amino]-12-oxododecyl ester

Results and discussion

Applicant's summary and conclusion