Registration Dossier

Administrative data

Endpoint:
partition coefficient
Type of information:
experimental study
Adequacy of study:
key study
Study period:
From 16 February to 03 May 2016
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Cross-reference
Reason / purpose:
other: Reference to the validated analytical method used for the quantification of the octanol and water samples.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2016
Report Date:
2016

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
EU Method A.8 (Partition Coefficient)
Version / remarks:
2008
Deviations:
no
Qualifier:
according to
Guideline:
OECD Guideline 107 (Partition Coefficient (n-octanol / water), Shake Flask Method)
Version / remarks:
1995
Deviations:
no
Qualifier:
according to
Guideline:
EPA OPPTS 830.7550 (Partition Coefficient, n-octanol / H2O, Shake Flask Method)
Version / remarks:
1996
Deviations:
no
GLP compliance:
yes (incl. certificate)
Type of method:
flask method
Partition coefficient type:
octanol-water

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid
Details on test material:
- Appearance: Brown coloured, brittle solid
- Storage condition of test material: At room temperature
- Chemical name: Zinc modified rosinate, hydrogenated zinc rosinate
- CAS No.: 68425-02-5

Study design

Analytical method:
other: ultra-performance liquid chromatography

Results and discussion

Partition coefficient
Key result
Type:
log Pow
Partition coefficient:
4.3
Temp.:
20 °C
pH:
7
Details on results:
MAIN STUDY 1
- The analysed concentration of the stock solution was 4.90 g/L; nominal quantity of the substance in each test sample was 9.81 mg. Recoveries: 82% - 104%.
- No test substance was detected in the pretreated phases from the blank test sample.
- The log Pow values were within the criterion range of ± 0.3 log units.
- pH values of 7.4 to 8.1 were measured. These values deviate from the pH of the buffer used (i.e.pH 7). Therefore a second main study was performed.

MAIN STUDY 2
- The analysed concentration of the stock solution was 3.69 g/L, while the nominal concentration was only 1.02 g/L. It is technically not possible to achieve a higher concentration than the nominal concentration. The analysed concentration of the stock solution was, therefore, considered inaccurate. Samples of the stock solution might have been contaminated during sample preparation. Due to this, the nominal concentration was used for the calculation of the recoveries. The nominal quantity of the substance in each test sample was 2.04 mg. Recoveries: 99% - 104%.
- The log Pow values were within a range of ± 0.4 log units which slightly exceeded the criterion of ± 0.3 log units. The results were accepted, as the criterion was only slightly exceeded and the average log Pow of main study 2 was in good agreement with the average log Pow of Main study 1
- A significant peak at the retention time of the test item was detected in the pretreated samples from the blank mixture. The samples from the blank mixture were probably contaminated in course of sample treatment. As the resulting partition coefficient in Main study 2 agreed with the result of Main study 1, where no signal was observed in the blank samples from the blank mixture, this was considered not to have any impact on the integrity of the study.

KEY RESULT
The mean log Pow of Main study 1 and the mean log Pow of Main study 2 were in agreement. The overall mean of both main studies was therefore reported as the log Pow of the substance. The deviation of the pH as observed in Main study 1 seemed to have had no impact on the outcome of the study.

Any other information on results incl. tables

Table: Shake-flask results Main study 1

  

Ratio
n-octanol : water
[v:v]

Analysed concentration

Pow

log Pow

pH

n-octanol
[g/L]

water
[g/L]

individual

mean

 

 

 

 

 

 

 

1:1

1.5 (1)

0.000060 (1)

2.5E04

2.3E04

4.4

7.5

 

1.5 (1)

0.0000726

2.1E04

 

4.3

7.5

 

 

 

 

 

 

 

1:2

2.0 (1)

0.0000904

2.2E04

2.2E04

4.3

7.4

 

1.9 (1)

0.0000869

2.2E04

 

4.3

7.4

 

 

 

 

 

 

 

2:1

1.3 (1)

0.000116

1.1E04

1.1E04

4.0

8.1

 

1.2 (1)

0.000112

1.1E04

 

4.0

8.1

 

 

 

 

 

 

 

Mean

1.9E04

 

4.3

 

Standard deviation

6.2E03

 

 

 

 

(1) Estimated value, calculated by extrapolation of the calibration curve.

Table: Shake-flask results Main study 2

 

Ratio
n-octanol : water
[v:v]

Analysed concentration

Pow

log Pow

pH

n-octanol
[g/L]

water
[g/L]

individual

mean

 

 

 

 

 

 

 

1:1

0.339

0.0000134

2.5E04

1.7E04

4.4

7.0

 

0.343

0.0000420

8.2E03

 

3.9

7.0

 

 

 

 

 

 

 

1:2

0.525

0.0000246

2.1E04

1.9E04

4.3

7.0

 

0.529

0.0000327

1.6E04

 

4.2

7.0

 

 

 

 

 

 

 

2:1

0.253

0.0000393

6.4E03

1.6E04

3.8

7.0

 

0.252

0.000010 (1)

2.5E04

 

4.4

7.0

 

 

 

 

 

 

 

Mean

1.7E04

 

4.2

 

Standard deviation

8.3E03

 

 

 

 

 

 

 

 

 

 

  (1) Estimated value, calculated by extrapolation of the calibration curve.

 

Applicant's summary and conclusion

Conclusions:
The log Pow of the substance at pH 7 and 20°C was determined to be 4.3.
Executive summary:

The partition coefficient of the substance was determined using the shake-flask method in a GLP study according to EC A.8, OECD 107 and OPPTS 830.7550. Quantitative analysis was performed by UPLC-MS. The log Pow of the substance at pH 7 and 20°C was determined to be 4.3.