Registration Dossier

Administrative data

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

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2018
Report Date:
2018

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 117 (Partition Coefficient (n-octanol / water), HPLC Method)
Version / remarks:
adopted 13. April 2004
Deviations:
no
Qualifier:
according to
Guideline:
EU Method A.8 (Partition Coefficient - HPLC Method)
Version / remarks:
published on 31. May 2008
Deviations:
no
Qualifier:
according to
Guideline:
other: Commission Regulation (EU) 2016/266 adopted 7 December 2015 amending Regulation EC No. 440/2008, Method A.24 “Partition Coefficient (n-octanol/water), High Performance Liquid Chromatography (HPLC) Method
Deviations:
no
GLP compliance:
no
Type of method:
HPLC method
Partition coefficient type:
octanol-water

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Storage conditions: Room Temperature (20 ± 5 °C)
- Expiry date: 16. Dec. 2019

Study design

Analytical method:
high-performance liquid chromatography

Results and discussion

Partition coefficient
Type:
log Pow
Partition coefficient:
3.682
Temp.:
25 °C
Remarks on result:
other: no further information available

Applicant's summary and conclusion

Conclusions:
The log Pow of the test item is stated as 3.682 at 25 °C.
The study was performed according to the OECD TG117, EU Method A.8 and EC Regulation Method A.24 without deviations and therefore considered to be of the highest quality (reliability Klimisch 1).The validity criteria are fulfilled.
Executive summary:

The partition coefficient of the test item was determined in a study according to OECD 117 resp. EU Method A.8. resp. EC Regulation Method A.24. The study was performed using a HPLC with a C18 column. Seven reference items with different retention times and thiourea for the determination of the dead time were used to produce a calibration curve, since retention time on hydrophobic columns and POW are correlated. The reference items were chosen based on the results of the pre-test.

One vial was filled with the reference item mix and one vial with the test item solution. The vials were analysed using the HPLC with the program described below. First one injection from the solvent blank methanol/water 75/25 (v/v) was made. Then three injections were measured from the reference item mix, three injections from the test item and again three injections from the reference item mix.
For each reference item, the capacity factor k was calculated from the retention time of thiourea and the retention time of the respective reference item.

A calibration function (log k versus log POW, linear fit) was determined using the literature values for POW of the reference items and the retention times in the six determinations. 

The chromatogram of the test item gave one peak. With the calibration function log k versus log POW, the corresponding log POW value of the test item peak was determined with:

 

Mean Area
[mAU*min]
[1]

Relative Area
[%]

Mean Retention Time
[min]

log POW
±Standard Deviation

97.627 

100

5.140 

3.68±0.00 

[1]mAU = milli absorbance units

 

This value is the mean ± standard deviation of three independent determinations.