Registration Dossier

Diss Factsheets

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:
05.-21.05.2014
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to guideline
Guideline:
EU Method A.8 (Partition Coefficient)
Deviations:
no
Qualifier:
according to guideline
Guideline:
OECD Guideline 117 (Partition Coefficient (n-octanol / water), HPLC Method)
Deviations:
no
GLP compliance:
no
Type of method:
HPLC method
Partition coefficient type:
octanol-water
Analytical method:
high-performance liquid chromatography
Key result
Type:
log Pow
Partition coefficient:
> 6.5
Temp.:
20 °C
Remarks on result:
other: pH not relevant
Details on results:
Based on the preliminary study the partition coefficient was calculated to be greater than 3.4. The program KOWWIN (part of EPI Suite) was used for calculating the log Pow of the test item. The calculated value was 9.4.
Therefore according to the guidelines the partition coefficient n-octanol/water of the test item at room temperature was determined by the HPLC method.

Preliminary visual estimation of the water solubility

Different amounts of the test item and water were stirred at room temperature until the mixture appeared dissolved or the water solubility could be estimated to be below 10 mg/L.

Amount of the test item in mg

Total volume in mL

Appearance of mixture

10.7

100

undissolved

11.3

500

undissolved

3.5

500

undissolved

The solubility of the test item in water was found to be below 7.0 mg/L (without correction of the purity).

Preliminary visual estimation of the n-octanol solubility

Increasing amounts of the test item were stirred with a defined volume of n-octanol at room temperature and visually checked for any undissolved parts.

Added amount of test item in mg

Amount of test item (total) in mg

Added volume of n-octanol in mL

Volume n-octanol (total) in mL

Stirring time

Appearance mixture

34.1

34.1

2

2

30 min

dissolved

97.0

131.1

-

2

50 min

undissolved

 

The solubility of the test item in n-octanol was found to be between 17.1 g/L and 65.6 g/L (without correction of the purity).

Table 1: Calibration data 1st injection

Calibration substance

tR / min

k

log k

log Pow

2-Butanone

1.12

0.11

-0.97

0.3

Acetanilide

1.09

0.07

-1.14

1.0

Cinnamyl alcohol

1.14

0.12

-0.91

1.9

2,6-Dichlorobenzonitrile

1.25

0.24

-0.62

2.6

Allyl phenyl ether

1.33

0.31

-0.51

2.9

Benzophenone

1.35

0.33

-0.48

3.2

Cumene

1.62

0.60

-0.22

3.7

Diphenyl ether

1.50

0.48

-0.32

4.2

Fluoranthene

1.94

0.91

-0.04

5.1

4,4'-DDT

2.19

1.17

0.07

6.5

 

logPow =a + b- logk

 

Parameters: a = 5.42 b = 4.43 r2 = 0.9156

 

log Pow of the test item - 1st injection

 

tR / min

k

log k

log Pow

Test item

23.24

21.97

1.34

> 6.5*
(11.4)**

*above the highest log Povv value of calibration substances (4,4-DDT)
**via extrapolation

  

Table 2: Calibration data 2nd injection

Calibration substance

tR / min

k

log k

log Pow

2-Butanone

1.12

0.11

-0.96

0.3

Acetanilide

1.09

0.07

-1.13

1.0

Cinnamyl alcohol

1.14

0.12

-0.91

1.9

2,6-Dichlorobenzonitrile

1.26

0.24

-0.62

2.6

Allyl phenyl ether

1.33

0.31

-0.51

2.9

Benzophenone

1.35

0.33

-0.48

3.2

Cumene

1.62

0.60

-0.22

3.7

Diphenyl ether

1.50

0.48

-0.32

4.2

Fluoranthene

1.94

0.91

-0.04

5.1

4,4'-DDT

2.20

1.17

0.07

6.5

Parameters: a = 5.41 b = 4.44 r2 = 0.9143

Table 3: log Pow of the test item - 2nd injection

 

tR / min

k

log k

log Pow

Test item

23.39

22.11

1.34

> 6.5*
(11.4)**

*above the highest log Povv value of calibration substances (4,4-DDT)
**via extrapolation

The partition coefficient n-octanol/water of the test item was determined according to the HPLC method.

It was found to be:

log Pow > 6.5(*)

log Pow = 11.4 (**)

(*) above the highest log Pow value of calibration substances (4,4'-DDT)

(**) via extrapolation

Conclusions:
The mean partition coefficient of the test item was determined to be above logPow = 6.5 (highest standard).The log Pow was estimated via extrapolation to be log Pow = 11.4.
Executive summary:

The partition coefficient n-octanol/water of the test item was determined according to OECD Guideline 117 and EU Method A.8. Based on the preliminary results and calculation by EPI Suite, the log Pow value was determined by using the HPLC Method.

The test item was dissolved in acetonitrile using the ultrasonic bath and diluted from 0.1 mL to 1 mL with acetonitrile / distilled water 95:5 % (v/v) and injected as single solutions twice. The dead time marker and the calibration samples each were dissolved in acetonitrile and diluted from 0.1 mL to 1 mL with acetonitrile / distilled water 95:5 % (v/v) and injected as single solutions twice.

Retention times tR were measured and averaged and the decimal logarithms of the capacity factors k were calculated. The linear regression parameters of the relationship log Pow = f(log k) were also calculated from the data obtained with the calibration mixture and, therewith, log Pow of the test substance was determined from its measured capacity factor. The mean partition coefficient of the test item was determined to be above logPow = 6.5 (highest standard).The log Pow was estimated via extrapolation to be log Pow = 11.4.

Description of key information

The mean partition coefficient of the test item was determined to be above logPow = 6.5 (highest standard).The log Pow was estimated via extrapolation to be log Pow = 11.4.

Key value for chemical safety assessment

Log Kow (Log Pow):
11.4
at the temperature of:
25 °C

Additional information

The partition coefficient n-octanol/water of the test item was determined according to OECD Guideline 117 and EU Method A.8. Based on the preliminary results and calculation by EPI Suite, the log Pow value was determined by using the HPLC Method.

The test item was dissolved in acetonitrile using the ultrasonic bath and diluted from 0.1 mL to 1 mL with acetonitrile / distilled water 95:5 % (v/v) and injected as single solutions twice. The dead time marker and the calibration samples each were dissolved in acetonitrile and diluted from 0.1 mL to 1 mL with acetonitrile / distilled water 95:5 % (v/v) and injected as single solutions twice.

Retention times tR were measured and averaged and the decimal logarithms of the capacity factors k were calculated. The linear regression parameters of the relationship log Pow = f(log k) were also calculated from the data obtained with the calibration mixture and, therewith, log Pow of the test substance was determined from its measured capacity factor. The mean partition coefficient of the test item was determined to be above logPow = 6.5 (highest standard).The log Pow was estimated via extrapolation to be log Pow = 11.4.

Categories Display