Nonanedioic acid, 1,9-bis(2-octyldodecyl) ester

Partition coefficient

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

partition coefficient

Type of information:

(Q)SAR

Adequacy of study:

supporting study

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

Justification for type of information:

1. SOFTWARE
EPI Suite v4.10 Estimation Programs Interface Suite™ for Microsoft® Windows v 4.10. US EPA, United States Environmental Protection Agency, Washington, DC, USA.

2. MODEL (incl. version number)
KOWWIN v1.68

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 "Overall remarks, attachments" section.

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: EPI Suite v4.10
- Model(s) used: KOWWIN v1.68
The octanol-water partition coefficient of organic compounds is estimated starting from the chemical structure, which is divided into fragments (atom or larger functional groups). Coefficient values of each fragment or group are summed together to yield the log P estimate. For the complete method's description see field 'Any other information on materials and methods incl. tables'.
The datasets used for the model development (2447 molecules) and for the external validation (10946 molecules) are described in the field 'Any other information on materials and methods incl. tables'.
- Model description: see field 'Justification for type of 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 'overall remarks'

GLP compliance:

no

Type of method:

other: QSAR

Partition coefficient type:

octanol-water

Type:

log Pow

Partition coefficient:

21.38

QSAR result; pH and temperature are not reported. For detailed description of the model and its applicability, see "Any other information on materials and methods incl. tables".

Reference 2

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

16-22 Sep 2008

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient)

Deviations:

yes

Remarks:

As in the preliminary test it turned out that the log Kow of the test item exceeded maximal recommended value for the HPLC method (and thus for the shake-flask method), only the lower limit was estimated

Qualifier:

according to guideline

Guideline:

other: internal guideline VTA34N00004.01

Principles of method if other than guideline:

Comparison between the test and the reference substance

GLP compliance:

yes

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Type:

log Pow

Partition coefficient:

> 5.7

Remarks on result:

other: pH and temperature not reported

The test item elutes after 138 minutes, the reference item triphenylamine after 3.4 minutes.

Due to the principle of the HPLC method, reference items elute the later, the higher the log Pow value is. In conclusion, the test item exhibits a log Pow value significantly higher than the reference item.

The reference item triphenylamine is listed in the EU test procedure with the second highest log Pow value (=5.7). Furthermore, the test procedure is applicable within log Pow values from-2 to +6. Thus, based on the preliminary results, log Pow can be estimated as > 5.7.

To fulfill the requirements of the test procedure, the HPLC run was repeated with 75% methanol / 25% water. As expected, even after 480 minutes the test item did not elute from the HPLC column.

Description of key information

log Pow  >  5.7

Additional information

There was an attempt performed, to determine the partition coefficient of the substance nonanedioic acid, bis(2-octyldodecyl) ester (CAS 897626-46-9) according to the EC Guideline A.8. As the log Pow value was outside the range of the validity of the method applied (HPLC), it could only be estimated by means of the preliminary test that log Pow exceeded the value reported for the reference substance triphenylamine. QSAR (KOWWIN v1.68) supported this estimation.