BAP

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

26 February 2018 to 06 August 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient - Shake Flask Method)

Version / remarks:

EU Method A.23 (Slow-Stir) was also followed.

Deviations:

yes

Remarks:

see below:-

Principles of method if other than guideline:

The initial preparation of test solutions for determination of the partition coefficient was performed using the shake flask method, however subsequent surface tension analysis determined that the test item was surface active, and thus this method was not appropriate. The octanol solubility stirring test was used to prepare the test solutions for LC-MS analysis and the results were used in conjunction with the solubility results from the surface tension testing to estimate the partition coefficient.

GLP compliance:

yes

Type of method:

slow-stirring method

Remarks:

and slow-stir method

Partition coefficient type:

octanol-water

Specific details on test material used for the study:

- CAS Number: 1412893-78-7
- Physical Form: Tan Paste

Analytical method:

other: liquid chromatography mass spectrometry

Key result

Type:

log Pow

Partition coefficient:

1.51

Remarks on result:

other: Component 1

Key result

Type:

log Pow

Partition coefficient:

2.73

Remarks on result:

other: Component 2

Estimation of Partition Coefficient

From the surface tension determination, the water solubility value of the test item at 25.0 ± 1 °C was estimated to be 65.11 mg/L and 7.89 mg/L for mz/ 211 and m/z 262 respectively and the n-octanol solubility at 25.0 ± 1 °C was estimated to be 2109.2 mg/L and 4255.6 mg/L for mz/ 211 and m/z 262 respectively.

The estimated LogPow value was calculated using the equation:

Log10  Solubility in n­-Octanol / Solubility in Water

Partition Coefficient Results

Test	Solubility in n-Octanol (mg/L)	Solubility in Water (mg/L)	LogPow
m/z 211 Test 1	1815.1	64.56	1.45
m/z 211 Test 2	2403.2	65.68	1.56
m/z 211 Mean	2109.2	65.11	1.51
m/z 262 Test 1	2147.9	4.38	2.69
m/z 262 Test 2	2566.5	4.35	2.77
m/z 262 Mean	2357.2	4.37	2.73

Conclusions:

The partition coefficient of the test substance has been determined to be 1.51 (Component 1), and 2.73 (Component 2).

Executive summary:

In a study performed to the standardised guideline EU Test Method A.8 and A.23, under GLP conditions.

 

The initial preparation of test solutions for determination of the partition coefficient was performed using the shake flask method, however subsequent surface tension analysis determined that the test item was surface active, and thus this method was not appropriate. The octanol solubility stirring test was used to prepare the test solutions for LC-MS analysis and the results were used in conjunction with the solubility results from the surface tension testing to estimate the partition coefficient.

 

The partition coefficient of the test substance has been determined to be 1.51 (Component 1), and 2.73 (Component 2). 

Description of key information

In a study performed to the standardised guidelines EU Test Method A.8 and A.23, under GLP conditions.

 

The initial preparation of test solutions for determination of the partition coefficient was performed using the shake flask method, however subsequent surface tension analysis determined that the test material was surface active, and thus this method was not appropriate. The octanol solubility stirring test was used to prepare the test solutions for LC-MS analysis and the results were used in conjunction with the solubility results from the surface tension testing to estimate the partition coefficient.

 

The partition coefficient of the test material has been determined to be 1.51 (Component 1), and 2.73 (Component 2).