Registration Dossier
Registration Dossier
Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.
The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.
Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 303-161-8 | CAS number: 94158-87-9
Partition coefficient
Administrative data
Link to relevant study record(s)
- Endpoint:
- partition coefficient
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- April 20, 2018 - April 27, 2018
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- guideline study
- Qualifier:
- equivalent or similar to guideline
- Guideline:
- other: OECD 105 flask method
- Deviations:
- not applicable
- Principles of method if other than guideline:
- OECD 105 flask method
- GLP compliance:
- no
- Type of method:
- flask method
- Partition coefficient type:
- octanol-water
- Analytical method:
- high-performance liquid chromatography
- Key result
- Type:
- log Pow
- Partition coefficient:
- -4
- Temp.:
- 20 °C
- pH:
- ca. 4.2
- Executive summary:
The partition coefficient (n-octanol/water) of the test item was estimated based on the ratio of the individual solubilities of the test item in water and n-octanol. The solubilities were determined according to the flask method. The shake flask method and the HPLC method were not applicable due to the low log POW.
It was found to be without correction of the purity:
log POW = -4.0
Reference
Preliminary visual estimation of the n-octanol solubility
Defined amounts of the test item were stirred with increasing volumes of n-octanol at room temperature and visually checked for any undissolved parts.
Table4: Results of the preliminary visual estimation of the n-octanol solubility
Amount of test item / mg |
Added volume of n-octanol / mL |
Total volume of n-octanol / mL |
Stirring time / h |
Appearance of mixture |
10.5 |
5 |
5 |
~ 0.5 |
not dissolved |
45 |
50 |
0.25 |
not dissolved |
|
150 |
200 |
~ 56 |
not dissolved |
According to this preliminary test the solubility of the test item in n-octanol was below 53 mg/L (without correction for the purity).
Calculation of the partition coefficient log POWfrom the preliminary test
The partition coefficient POWmay be estimated from the saturation concentrations in n-octanol and water. The estimated partition coefficient was calculated with the water solubility data determined in project PS20180033.04 (cS = 358 g/L) andthe data obtained above. It was calculated to be: log POW < -3.8.
Due to the calculations the partition coefficient was estimated based on the ratio of the solubilities in water and octanol. The octanol solubility was determined using the flask method.The shake flask method and the HPLC method were not applicable due to the low log POW.
Determination of the solubility in n-octanol: Flask method
The individual saturation solubility of the test item in n-octanol was performed within this study. After that, the partition coefficient was estimated based on the ratio of the test item solubility in n-octanol and water. The flask method was performed as described above. The data for the evaluation are given in Table 5. The n-octanol solubility was calculated from the measured and unrounded concentration values and not from the rounded values given in Table 5.
Table5: n-Octanol solubility experiments of the test item
Experiment |
24 h experiment |
48 h experiment |
72 h experiment |
blank experiment (72 h) |
Amount of test item / mg |
16.2 |
16.9 |
12.8 |
-- |
Amount of octanol / mL |
20 |
20 |
20 |
20 |
Stirring time at 30 °C / h |
24 |
48 |
72 |
72 |
Dilution factor |
40 |
40 |
40 |
40 |
Measured concentration / mg/L |
0.65 / 0.68 |
0.73 / 0.73 |
0.87 / 0.88 |
-- / -- |
Mean concentration / mg/L |
0.66 |
0.73 |
0.88 |
-- |
n-Octanol solubility / mg/L |
26.5 |
29.1 |
35.1 |
-- |
The n-octanol solubilities of the test item showed an increasing tendency, but the individual values were still within the stability criterion of the guideline. As a conservative approach the highest value was stated as final result. The n‑octanol solubility at 20 °C was determined to be 35mg/L.
Calculation of the partition coefficient log POW from the individual solubilities
In project PS20180033.04 the water solubility of the test item at 20 °C was determined to be 358 g/L (± 6 g/L). Within this project the n-octanol solubility of the test item at 20 °C was determined to be 35 mg/L.
The partition coefficient POW of the test item was determined to be:
log POW = - 4.0
Description of key information
The partition coefficient (n-octanol/water) of the test item was estimated based on the ratio of the individual solubilities of the test item in water and n-octanol. The solubilities were determined according to the flask method.The shake flask method and the HPLC method were not applicable due to the low log POW.
It was found to be without correction of the purity:
log POW = -4.0
Key value for chemical safety assessment
- Log Kow (Log Pow):
- -4
- at the temperature of:
- 20 °C
Additional information
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
