Registration Dossier

Physical & Chemical properties

Partition coefficient

Currently viewing:

Administrative data

Link to relevant study record(s)

Reference
Endpoint:
partition coefficient
Type of information:
experimental study
Adequacy of study:
key study
Study period:
from 2018-05-03 to 2018-05-30
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to
Guideline:
OECD Guideline 107 (Partition Coefficient (n-octanol / water), Shake Flask Method)
Deviations:
no
Qualifier:
according to
Guideline:
EU Method A.8 (Partition Coefficient - Shake Flask Method)
Deviations:
no
Qualifier:
according to
Guideline:
EPA OPPTS 830.7550 (Partition Coefficient, n-octanol / H2O, Shake Flask Method)
Deviations:
no
GLP compliance:
yes (incl. certificate)
Type of method:
flask method
Partition coefficient type:
octanol-water
Analytical method:
high-performance liquid chromatography
Key result
Type:
log Pow
Partition coefficient:
-3.83
Temp.:
20 °C
pH:
>= 6.88 - <= 7.63
Type:
Pow
Partition coefficient:
0
Temp.:
20 °C
pH:
>= 6.88 - <= 7.63

Table - Measured concentrations

Ratio of solvents
(n-Octanol : Water)

Measured concentration in
n-octanol phase
(µg/mL)

Measured concentration in
aqueous phase
(µg/mL)

pH

10:1

0.23

1498.8

7.41

0.28

1587.1

7.29

0.27

1603.6

7.24

Mean

0.26

1563.1

7.31

RSD %

10

4

-

Measured quantity of test item (Mo; Mw)

11.8 µg

7112 µg

-

Total nominal quantity of test item (Ms)

7217 µg

Total quantity of test item (Mo + Mw)

7124 µg

Recovery

99 %

Ratio of solvents
(n-Octanol : Water)

Measured concentration in
n-octanol phase
(µg/mL)

Measured concentration in
aqueous phase
(µg/mL)

pH

20:1

0.38

2892.0

7.12

0.35

2963.4

7.17

0.39

2971.5

7.22

Mean

0.37

2942.3

7.17

RSD%

6

1

-

Measured quantity of test item (Mo; Mw)

17.7 µg

7061 µg

-

Total nominal quantity of test item (Ms)

7217 µg

Total quantity of test item (Mo + Mw)

7079 µg

Recovery

98 %

5:1

0.15

906.3

7.63

0.16

916.8

7.34

0.11

924.9

6.88

Mean

0.14

916.0

7.28

RSD%

19

1

-

Measured quantity of test item (Mo; Mw)

5.8 µg

7648 µg

-

Total nominal quantity of test item (Ms)

7217 µg

Total quantity of test item (Mo + Mw)

7654 µg

Recovery

106 %

Table - Calculated partition coefficient (Pow) and log Pow

Ratio of solvents
(n-Octanol : Water)

Partition coefficient

Log Partition coefficient

Pow

Log Pow

10:1

0.0002

-3.78

20:1

0.0001

-3.90

5:1

0.0002

-3.82

Mean all

0.0001

-3.83

 

Conclusions:
The partition coefficient (Pow) of the test item in an n-octanol / water two-phase system was determined to be 0.0001 using shake flask method. The logPow was determined to be -3.83 ± 0.055 (95 % confidence interval).
Executive summary:

A study was conducted in accordance with OECD TG 107, Regulation (EC) No 440/2008 method A.8 and OPPTS 830.7550 to determine the partition coefficient of the test item using the shake flask method. A stock solution of known concentration (~ 0.8 g/L) of the test substance in n-octanol, pre-saturated with water, was prepared. The samples were extracted with ultrapure water in 1:1 volume ratio. The phases were separated by centrifugation (4000 rpm, 5 min, 20 °C) and the aqueous phase was diluted with ultrapure water for HPLC analysis. The samples of n-octanol phases were concentrated with ultrapure water, then directly measured by HPLC. The samples of water phases were diluted with ultrapure water before the HPLC analysis. Test vessels with octanol/water mixture in three different ratios were shaken for 5 minutes by hand. Separation of the two phases was achieved by centrifugation at 20 °C (5 min, 4000 rpm). Then the two phases were analysed using HPLC. The partition coefficient (Pow) of the test item in an n-octanol / water two-phase system was determined to be 0.0001 using shake flask method. The logPow was determined to be -3.83 ± 0.055 (95 % confidence interval).

Description of key information

The partition coefficient (Pow) of the test item in an n-octanol / water two-phase system was determined to be 0.0001 using shake flask method. The logPow was determined to be -3.83 ± 0.055 (95 % confidence interval).

Key value for chemical safety assessment

Log Kow (Log Pow):
-3.83
at the temperature of:
20 °C

Additional information

A study was conducted in accordance with OECD TG 107, Regulation (EC) No 440/2008 method A.8 and OPPTS 830.7550 to determine the partition coefficient of the test item using the shake flask method. A stock solution of known concentration (~ 0.8 g/L) of the test substance in n-octanol, pre-saturated with water, was prepared. The samples were extracted with ultrapure water in 1:1 volume ratio. The phases were separated by centrifugation (4000 rpm, 5 min, 20 °C) and the aqueous phase was diluted with ultrapure water for HPLC analysis. The samples of n-octanol phases were concentrated with ultrapure water, then directly measured by HPLC. The samples of water phases were diluted with ultrapure water before the HPLC analysis. Test vessels with octanol/water mixture in three different ratios were shaken for 5 minutes by hand. Separation of the two phases was achieved by centrifugation at 20 °C (5 min, 4000 rpm). Then the two phases were analysed using HPLC. The partition coefficient (Pow) of the test item in an n-octanol / water two-phase system was determined to be 0.0001 using shake flask method. The logPow was determined to be -3.83 ± 0.055 (95 % confidence interval).