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 November 17, 2016 to November 23, 2016
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
GLP compliance:
not specified
Type of method:
flask method
Partition coefficient type:
octanol-water
Specific details on test material used for the study:
Test substance name: Phosphoric acid, mono-and di-C8-C10-(even numbered)-alkyl esters
Batch: 205624/01
Appearance: liquid
Analytical method:
other: Liquid-chromatography with ELSD detector
Key result
Type:
log Pow
Partition coefficient:
0.963
Temp.:
23 °C
pH:
ca. 5.66 - 6.03
Key result
Type:
Pow
Partition coefficient:
> 5.78 - < 12.58
Temp.:
23.2 °C
pH:
ca. 7
Details on results:
Total average over 6 independent determinations: Pow = 9.18 ± 3.4 and Log Pow = 0.963

Table 1: Concentrations of the different test solutions in 1-octanol phase and aqueous phase

Test mixture

Concentration of test substance [mg/g], 1-octanol phase

Concentration of test substance

[µg/g], aqueous phase

1

2.427

0.417

2

2.437

0.418

3

2.417

0.289

4

2.422

0.287

5

2.444

0.185

6

2.428

0.181

 

Table 2. Calculated Pow and log Powvalues

Test mixture

Pow

log Pow

AveragePow

Average log Pow

1

5.817

0.765

918±3.4

0.963

2

5.836

0.766

3

8.371

0.923

4

8.441

0.926

5

13.125

1.122

6

13.383

1.127

Conclusions:
Under the study conditions, the partition coefficient of the substance was determined to be 0.963 (log Pow) and 9.18 ± 3.4 (Pow) at 23.0°C and pH 5.66 to 6.03 respectively.
Executive summary:

A study was conducted to determine the partition coefficient of the test substance according to OECD Guideline 107. Preliminary tests showed that the shake flask method was a suitable method. No reference substance was used in this test and the test system was calibrated using the test substance. For the preparation of the test mixtures, a stock solution was created by dissolving 211.21 mg of the test substance in 100 mL 1-octanol (pre-saturated with buffer solution pH 7.0) . The test mixtures were prepared by adding buffer solution (pre-saturated with 1-octanol) to the stock solution. These test mixtures were stirred thoroughly for 2 h at 23.0°C. Phase separation was then achieved by centrifugation (15 min, 3500 RPM). The concentrations of the different test solutions were determined using liquid chromatography with UV detector. Under the study conditions, the partition coefficient of the substance was determined to be 0.963 (log Pow) and 9.18 ± 3.4 (Pow) at 23.0°C and pH 5.66 to 6.03 respectively (Schwarzkopf, 2016).

Description of key information

The partition coefficient was determined according to OECD Guideline 107 (Schwarzkopf, 2016).

Key value for chemical safety assessment

Log Kow (Log Pow):
0.963
at the temperature of:
23 °C

Additional information