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
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:
EPA OPPTS 830.7550 (Partition Coefficient, n-octanol / H2O, Shake Flask Method)
Deviations:
no
Qualifier:
according to
Guideline:
EU Method A.8 (Partition Coefficient - Shake Flask Method)
Deviations:
no
GLP compliance:
yes
Type of method:
other: Shake flask method
Partition coefficient type:
octanol-water
Analytical method:
high-performance liquid chromatography
Key result
Type:
log Pow
Partition coefficient:
1.24
Temp.:
20 °C
Remarks on result:
other: Octanol-double distilled water
Key result
Type:
log Pow
Partition coefficient:
1.23
Temp.:
20 °C
pH:
4
Key result
Type:
log Pow
Partition coefficient:
1.26
Temp.:
20 °C
pH:
7
Key result
Type:
log Pow
Partition coefficient:
1.24
Temp.:
20 °C
pH:
9
Type:
Pow
Partition coefficient:
17.548
Temp.:
20 °C
Remarks on result:
other: Octanol-double distilled water
Type:
Pow
Partition coefficient:
17.092
Temp.:
20 °C
pH:
4
Type:
Pow
Partition coefficient:
18.067
Temp.:
20 °C
pH:
7
Type:
Pow
Partition coefficient:
17.354
Temp.:
20 °C
pH:
9
Details on results:
The analysed concentration of the test substance stock solutions prepared in n-octanol presaturated for the tests with double distilled water and pH 4.0, 7.0, and 9.0 aqueous buffer solutions were 8.02, 7.78, 7.71, and 8.25 µg/mL, respectively.
It is concluded that the pH has no significant effect on octanol-water partition coefficient of the test substance
Conclusions:
log Pow: 1.24 ± 0.01 (octonal-double distilled water), 1.23 ± 0.01 (pH 4.0), 1.26 ± 0.01 (pH 7.0), 1.24 ± 0.02 (pH 9.0)
Pow: 17.548 ± 0.553 (octonal-double distilled water), 17.092 ± 0.436 (pH 4.0), 18.067 ± 0.353 (pH 7.0), 17.354 ± 0.867 (pH 9.0)
Executive summary:

The study was conducted to determine the partition coefficient of the test substance, according to regulatory guidelines: OECD Guideline 107, OPPTS 830.7550 and EEC Method A.8. The study was conducted using n-octanol, double distilled water and pH 4.0, 7.0 and 9.0 aqueous buffer solutions to determine the effect of pH on the partition coefficient of the test substance. Measured volumes of n-octanol and double distilled water or buffer solutions, so as to give 1:1, 1:2, and 2:1 ratios, were shaken along with the test substance until equilibrium was achieved. The phases were then separated and the concentration of the test substance in each phase was determined using a validated analytical method. The partition coefficient was then calculated.

The overall mean partition coefficient Pow and log Pow of the test substance at 20 ± 1ºC is presented below.

log Pow: 1.24 ± 0.01 (octonal-double distilled water), 1.23 ± 0.01 (pH 4.0), 1.26 ± 0.01 (pH 7.0), 1.24 ± 0.02 (pH 9.0)

Pow: 17.548 ± 0.553 (octonal-double distilled water), 17.092 ± 0.436 (pH 4.0), 18.067 ± 0.353 (pH 7.0), 17.354 ± 0.867 (pH 9.0)

It is concluded that the pH has no significant effect on octanol-water partition coefficient of the test substance

Description of key information

OECD Guideline 107

Key value for chemical safety assessment

Log Kow (Log Pow):
1.26
at the temperature of:
20 °C

Additional information