Diisopropylbiphenyl and triisopropylbiphenyl

Biodegradation in soil

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

biodegradation in soil: simulation testing

Type of information:

(Q)SAR

Remarks:

Diisopropyl biphenyl isomer mixture (DIPB; CAS-No.: 69009-90-1) represents one main constituent of the registered UVCB (Alkylation and transalkylation products of biphenyl with propene)

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model, but not (completely) falling into its applicability domain, with adequate and reliable documentation / justification

Remarks:

The substance is not compliant with the applicability domain of the model. However, this calculation is used as supporting information and is considered acceptable for this purpose. It is adequately documented and justified. For more detail see field `overall remarks, attachments´.

Justification for type of information:

1. SOFTWARE
Vega version 1.1.4

2. MODEL (incl. version number)
Persistence in soil Model version 1.0.0

3. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL
See “Test material information”

4. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
See attached information on the model provided by the developer. Further information on the OECD criteria as outlined by the applicant is provided below under "Any other information of materials and methods incl. tables"

5. APPLICABILITY DOMAIN
See attached information and information as provided in "Any other information on results incl. tables".

6. ADEQUACY OF THE RESULT
See assessment of adequacy as outlined in the "Overall remarks, attachments" section.

Qualifier:

according to guideline

Guideline:

other: REACH Guidance on QSARs R.6

Principles of method if other than guideline:

- Software tool(s) used including version: Vega v1.1.4
- Model(s) used: Persistence in soil Model version 1.0.0

Full reference and details of the used formulas can be found in:
A. Manganaro, F. Pizzo, A. Lombardo, A. Pogliaghi, E. Benfenati, “Predicting persistence in the sediment compartment with a new automatic software based on the k-Nearest Neighbor (k-NN) algorithm”, Chemosphere (2015), accepted paper.
Gouin, T., Cousins, I., Mackay, D., “Comparison of two methods for obtaining degradation halflives”, Chemosphere 56, 2004, 531-535
Gramatica, P., Papa, E., “Screening and ranking of POPs for Global Half-Life: QSAR approaches for prioritization based on molecular structure”, Environ. Sci. Technol. 41, 2007, 2833-9.

- Model description: see field 'Justification for non-standard information', 'Attached justification' and 'any other information on Material and methods'
- Justification of QSAR prediction: see field 'Justification for type of information', 'Attached justification' and/or 'overall remarks'

GLP compliance:

no

Radiolabelling:

no

Oxygen conditions:

aerobic

Remarks on result:

other: DIPB was predicted to be not persistent (nP) in soil.

Transformation products:

not specified

For detailed information on the results please refer to the attached report.

Reference 2

Endpoint:

biodegradation in soil: simulation testing

Type of information:

(Q)SAR

Remarks:

Triisopropyl biphenyl isomer mixture (TIPB; CAS-No.: 29225-91-0) represents one main constituent of the registered UVCB (Alkylation and transalkylation products of biphenyl with propene)

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model, but not (completely) falling into its applicability domain, with adequate and reliable documentation / justification

Remarks:

The substance could be out of the applicability domain of the model. However, this calculation is used as supporting information and is considered acceptable for this purpose. It is adequately documented and justified. For more detail see field `overall remarks, attachments´.

Justification for type of information:

1. SOFTWARE
Vega version 1.1.4

2. MODEL (incl. version number)
Persistence in soil Model version 1.0.0

3. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL
See “Test material information”

4. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
See attached information on the model provided by the developer. Further information on the OECD criteria as outlined by the applicant is provided below under "Any other information of materials and methods incl. tables"

5. APPLICABILITY DOMAIN
See attached information and information as provided in "Any other information on results incl. tables".

6. ADEQUACY OF THE RESULT
See assessment of adequacy as outlined in the "Overall remarks, attachments" section.

Qualifier:

according to guideline

Guideline:

other: REACH Guidance on QSARs R.6

Principles of method if other than guideline:

- Software tool(s) used including version: Vega v1.1.4
- Model(s) used: Persistence in soil Model version 1.0.0

Full reference and details of the used formulas can be found in:
A. Manganaro, F. Pizzo, A. Lombardo, A. Pogliaghi, E. Benfenati, “Predicting persistence in the sediment compartment with a new automatic software based on the k-Nearest Neighbor (k-NN) algorithm”, Chemosphere (2015), accepted paper.
Gouin, T., Cousins, I., Mackay, D., “Comparison of two methods for obtaining degradation halflives”, Chemosphere 56, 2004, 531-535
Gramatica, P., Papa, E., “Screening and ranking of POPs for Global Half-Life: QSAR approaches for prioritization based on molecular structure”, Environ. Sci. Technol. 41, 2007, 2833-9.

- Model description: see field 'Justification for non-standard information', 'Attached justification' and 'any other information on Material and methods'
- Justification of QSAR prediction: see field 'Justification for type of information', 'Attached justification' and/or 'overall remarks'

GLP compliance:

no

Radiolabelling:

no

Oxygen conditions:

aerobic

Remarks on result:

other: TIPB was predicted to be vP in soil.

Transformation products:

not specified

For detailed information on the results please refer to the attached report.

Reference 3

Endpoint:

biodegradation in soil: simulation testing

Data waiving:

study technically not feasible

Justification for data waiving:

other:

Transformation products:

no

Description of key information

Alkylation and transalkylation products of biphenyl with propene is an UVCB substance composed of different constituents. Each constituent is present as a mixture of isomers with unknown constituents. Based on the complex composition in combination with the physico-chemical properties of the substance biodegradation simulation testing is technically not feasible. This was assessed within a feasibility study conducted according to OECD 309 guideline. In a weight of evidence approach, considering study results and QSAR estimates for the main constituents of the UVCB, it was concluded that alkylation and transalkylation products of biphenyl with propene is potentially persistent or very persistent.

Additional information

Based on the complex composition in combination with the physico-chemical properties of the substance biodegradation simulation testing is considered as technically not feasible. This was assessed within a feasibility study conducted according to OECD 309 guideline. Persistence in soil was estimated by QSAR calculations for the two main constituents DIPB and TIPB. These QSAR results were used in a weight of evidence approach for the persistence assessment of the UVCB substance.

The persistence of the main constituents DIPB and TIPB in soil was estimated using the QSAR model VEGA 1.1.4 “Persistence (soil) model” (IRFMN) 1.0.0. For DIPB the model predicts no persistence (nP) whereas the prediction for TIPB is very persistent (vP). The QSAR estimate for DIPB should be considered with caution, since the substance does not fall within the applicability domain of the model. For both isomers, DIPB and TIPB, the performance of the model on similar molecules is good, even though isopropyl chains are missing in the list of the most similar substances in the training set. The use of the prediction as supporting information within a weight of evidence approach for the persistency assessment of the UVCB substance is considered acceptable.