Registration Dossier

Environmental fate & pathways

Biodegradation in water: screening tests

Administrative data

biodegradation in water: ready biodegradability
Type of information:
Adequacy of study:
disregarded due to major methodological deficiencies
3 (not reliable)
Rationale for reliability incl. deficiencies:
results derived from a valid (Q)SAR model, but not (completely) falling into its applicability domain, and documentation / justification is limited

Data source

Reference Type:
other: QSAR model
Ready Biodegradability model (IRFMN) 1.0.9

Materials and methods

Test guideline
equivalent or similar to
other: ECHA guidance on information requirements and chemical safety assessment Chapter R.6: QSARs and grouping of chemicals.

Test material

Details on test material:
The SMILES included in the reference substance linked in Section 1 (General information) was used as model input.

Study design

Details on study design:
The applicability domain of predictions is assessed using an Applicability Domain Index (ADI) that has values from 0 (worst case) to 1 (best case). The ADI is calculated by grouping several other indices, each one taking into account a particular issue of the applicability domain. Most of the indices are based on the calculation of the most similar compounds found in the training and test set of the model, calculated by a similarity index that consider molecule's fingerprint and structural aspects (count of atoms, rings and relevant fragments).
For each index, including the final ADI, three intervals for its values are defined, such that the first interval corresponds to a positive evaluation, the second one corresponds to a suspicious evaluation and the last one corresponds to a negative evaluation.

List of indices:
- Similar molecules with known experimental value.
- Accuracy of prediction for similar molecules.
- Concordance for similar molecules.
- Atom Centered Fragments similarity check.
- Global AD Index.

Results and discussion

% Degradation
Key result
probability of ready biodegradability (QSAR/QSPR)
NON Readily Biodegradable

Any other information on results incl. tables

The result appears non-reliable as the predicted compound is outside the applicability domain of the model.

Applicant's summary and conclusion

Validity criteria fulfilled:
Interpretation of results:
not readily biodegradable
The substance is not readily biodegradable.