Registration Dossier

Administrative data

Endpoint:
partition coefficient
Type of information:
experimental study
Adequacy of study:
key study
Study period:
Testing was conducted between 26 March 2007 and 05 May 2007.
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Study conducted to GLP and in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not effect the quality of the relevant results.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2007
Report Date:
2007

Materials and methods

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

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
Sponsor's identification: C-Y9
Description: yellow powder
Lot number: MB-l
Date received: 06 March 2007
Storage conditions: room temperature, in the dark, over silica gel

Study design

Analytical method:
high-performance liquid chromatography

Results and discussion

Partition coefficient
Type:
log Pow
Partition coefficient:
-3.92
Temp.:
23 °C
pH:
7

Any other information on results incl. tables

Preliminary estimate

Approximate solubility in n-octanol:<1.10 x 10-2 g/l
Approximate solubility in water:      >291 g/l
Approximate Pow:  <3.79 x 10-5
Log10Pow:  <-4.42

Definitive test

The mean peak areas obtained for the standard, stock and sample solutions are shown in the following two tables:

Organic Phase

Solution

MeanArea

Standard 10.2 mg/l

161.930

Standard 10.1 mg/l

148.003

Sample 1

0.971

Sample 2

0.918

Sample 3

1.130

Sample 4

0.969

Sample 5

0.832

Sample 6

0.878

Aqueous Phase

Solution

MeanArea

Standard 251 mg/l

5.780 x 103

Standard 256 mg/l

5.927 x 103

Sample 1

5.940 x 103

Sample 2

5.943 x 103

Sample 3

5.917 x 103

Sample 4

5.933 x 103

Sample 5

5.926 x 103

Sample 6

5.917 x 103

Stock Solution A

5.840 x 103

Stock Solution B

5.834 x 103

The total weights (mg) and analysed concentration (mg/l) of the respective phases are shown in the following table:

Sample Number

Volume of Water Saturated

n-octanol (ml)

Volume of Stock Solution (ml)

Total Weight (mg)*

Organic Phase

Aqueous Phase

Analysed Concentration (mg/l)

Weight (mg)†

Analysed Concentration (mg/l)

Weight (mg)†

pH

1

125

25

25.3

0.127

1.58 x 10-2

1.03 x 103

25.7

7.2

2

125

25

25.3

0.120

1.50 x 10-2

1.03 x 103

25.7

7.2

3

110

11

11.1

0.147

1.62 x 10-2

1.03 x 103

11.3

7.2

4

110

11

11.1

0.126

1.39 x 10-2

1.03 x 103

11.3

7.2

5

280

14

14.2

0.109

3.04 x 10-2

1.03 x 103

14.4

7.2

6

360

18

18.2

0.115

4.13 x 10-2

1.03 x 103

18.5

7.2

pH of stock solution:                            7.0
Temperature:                                       23.0 ± 1.0°C


*From analysis of the stock solution

†From analysis of the respective phase

The partition coefficient determined for each sample is shown in the following table:

Sample Number

n-Octanol/Water Volume Ratio

Partition Coefficient

Log10Pow

Mean Partition Coefficient

1

5:1

1.23 x 10-4

-3.91

1.20 x 10-4

2

1.16 x 10-4

-3.93

3

10:1

1.44 x 10-4

-3.84

1.33 x 10-4

4

1.23 x 10-4

-3.91

5

20:1

1.06 x 10-4

-3.98

1.09 x 10-4

6

1.12 x 10-4

-3.95

Mean Pow :1.21 x 10-4             log10Pow:-3.92 Powstandard deviation : 1.31 x 10-5

Validation

The linearity of the detector response with respect to concentration was assessed over the nominal concentration range of 0 to 400 mg/l for the aqueous phases and 0 to 7.5 mg/l for the organic phases. These were satisfactory with a correlation coefficient of 1.000 and 0.999 respectively being obtained.

Discussion

The test material contained sulphonic acid sodium salt groups and therefore pKa values outside the environmentally relevant range for the determination of partition coefficient. As a result, testing was performed at pH 7 using the shake flask method recommended for salts

Applicant's summary and conclusion

Conclusions:
The partition coefficient of the test material has been determined to be log10 Pow -3.92.
Executive summary:

Partition Coefficient.

1.21 x 10-4 at 23.0 ± 1.0°C, log10 Pow -3.92, using the shake-flask method, Method A8 of Commission Directive 92/69/EEC and Method 107 of the DECD Guidelines for Testing of Chemicals, 27 July 1995.