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 117 (Partition Coefficient (n-octanol / water), HPLC Method)
Deviations:
no
Qualifier:
according to
Guideline:
other: EU Method A.24
Deviations:
no
GLP compliance:
not specified
Type of method:
HPLC method
Partition coefficient type:
octanol-water
Specific details on test material used for the study:
Batch No.: WD0066442; Purity: 100 % (UVCB); Appearance: amber, homogeneous liquid
Analytical method:
high-performance liquid chromatography
Key result
Type:
Pow
Partition coefficient:
>= 0.3 - < 6.2
Temp.:
25 °C
pH:
7
Details on results:
Only broad signals were obtained with a main part of peaks eluting after DDT (reference substance with highest log POW (log POW 6.2)). Therefore the test substance peak area was divided into 3 ranges using the retention times of the reference substances: log Kow ≤0.3, 0.3 – 6.2 and >6.2, corresponding to retention time sections: 1 – 1.7 min., 1.7 – 31.0 min and 31.0 – 72.0 min.
Although area is not necessarily correlated to absolute concentration if a UV detector is used, it is assumed that the peak area proportions, detected at 245 nm, is correlated to test item proportions.

The evaluation of the test item is presented in the following table:

Compound

RT Reference Mix

Time Window Test Sub.

Corresponding log POW range

Area Test Sub.

Relative Ar-ea Test Sub.

min.

mAU*min

%

Thiourea

1.4

1 – 1.7

≤ 0.3

22.928

4.63

2-Butanone

1.7

1.7 – 31.0

0.3 – 6.2

106.236

21.44

DDT

31.0

31.0 – 72.0

>6.2

366.400

73.94

Conclusions:
Under the study conditions, only broad signals for the test substance injection were obtained with a main part of peaks eluting after DDT (reference substance with highest log Kow. Therefore the test substance peak area was divided into 3 ranges using the retention times of the reference substances: log Kow ≤ 0.3, 0.3 – 6.2 and >6.2.
Executive summary:

A study was conducted to determine partition coefficient according to OECD Guideline 117 and EU Method A.24. The study was performed using a HPLC with a C18 column. Eight reference substances with different retention times and thiourea for the determination of the dead time were used to produce a calibration curve. Under the study conditions, only broad signals for the test substance injection were obtained with a main part of peaks eluting after DDT (reference substance with highest log Kow. Therefore the test substance peak area was divided into 3 ranges using the retention times of the reference substances: log Kow ≤ 0.3, 0.3 – 6.2 and >6.2 (Brinkmann, 2017).

Description of key information

The partition coefficient was determined according to OECD Guideline 117 and EU Method A.24 (Brinkmann, 2017).

Key value for chemical safety assessment

Log Kow (Log Pow):
6.2
at the temperature of:
25 °C

Additional information

log Kow lies within range of: ≤0.3, 0.3 – 6.2