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EC number: 266-369-7 | CAS number: 66469-15-6
Partition coefficient
Administrative data
Link to relevant study record(s)
- Endpoint:
- partition coefficient
- Type of information:
- calculation (if not (Q)SAR)
- Adequacy of study:
- supporting study
- Study period:
- 2017
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- accepted calculation method
- Qualifier:
- according to guideline
- Guideline:
- other: Calculation of the partition coefficient
- GLP compliance:
- no
- Type of method:
- estimation method (solubility ratio)
- Partition coefficient type:
- octanol-water
- Specific details on test material used for the study:
- Product description: Potassium isooctadecanoate/potassium isostearate
Name: Isooctadecanoic acid, potassium salt
CAS No.: 66469-15-6
Physical state: off white to yellowish solid at 20 °C
Batch No.: PFS-755-169
Re-certification date of batch: 12 December 2017
Purity: 100 % (UVCB)
pH, 10% in DI water 8.0 - 9.0
Stability: stable under test conditions
Storage condition of test material: Room temperature, protected from light - Analytical method:
- high-performance liquid chromatography
- Key result
- Type:
- log Pow
- Partition coefficient:
- -0.1
- Temp.:
- 20 °C
- Conclusions:
- The partition coefficient of the test item was calculated from the individual solubilities in n-octanol and water at 20 °C, respectively. The log Pow value can be reported as log Pow= - 0.10.
- Executive summary:
The partition coefficient of the test item was calculated from the individual solubilities in n-octanol and water at 20 °C, respectively. The log Pow value can be reported as log Pow= - 0.10.
- Endpoint:
- partition coefficient
- Type of information:
- calculation (if not (Q)SAR)
- Adequacy of study:
- key study
- Study period:
- 2018
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- accepted calculation method
- Justification for type of information:
- The results reported in the water solubility study of the test item were not considered relevant under environmental conditions (overestimating water solubility). Therefore the water solubility of a structural analogous substances (calcium stearate) was considered relevant under environmental conditions providing a realistic worst case scenario taking into account the structural similarities of the organic fatty acids (stearic acid and isostearic acid isomers). The 1-octanol solubility of the test item was determined in a separate study using a HPLC method. The partition coefficient is calculated from these individual solubilities: logPow = solubility of test item in n-octanol / solubility of test item in water.
Based on the similar chemical structure of calcium isostearate and calcium stearate the water solubility of 0.0007 mg/l (calcium stearate) is considered relevant to assess the water solubility of calcium isostearate. - Reason / purpose for cross-reference:
- reference to other study
- Reason / purpose for cross-reference:
- reference to other study
- Qualifier:
- according to guideline
- Guideline:
- other: Calculation of the partition coefficient
- Deviations:
- no
- GLP compliance:
- no
- Type of method:
- estimation method (solubility ratio)
- Partition coefficient type:
- octanol-water
- Specific details on test material used for the study:
- Product description: Potassium isooctadecanoate/potassium isostearate
Name: Isooctadecanoic acid, potassium salt
CAS No.: 66469-15-6
Physical state: off white to yellowish solid at 20 °C
Batch No.: PFS-755-169
Re-certification date of batch: 12 December 2017
Purity: 100 % (UVCB)
pH, 10% in DI water 8.0 - 9.0
Stability: stable under test conditions
Storage condition of test material: Room temperature, protected from light - Analytical method:
- high-performance liquid chromatography
- Key result
- Type:
- log Pow
- Partition coefficient:
- 8.36
- Temp.:
- 20 °C
- Remarks on result:
- other: log Kow calculated from water solubility of structural analogue substance.
- Conclusions:
- The partition coefficient of the test item was calculated from the individual solubilities in n-octanol and water (read across substance calcium stearate) at 20 °C, respectively. The log Pow value can be reported as log Pow = 8.36.
- Executive summary:
The partition coefficient of the test item was calculated from the individual solubilities in n-octanol and water (read across substance calcium stearate) at 20 °C, respectively. The log Pow value can be reported as log Pow = 8.36.
Referenceopen allclose all
Study Results
The partition coefficient of the test item is calculated from the individual solubilities of the test item in water and n-octanol, respectively.
The water solubility of the test item was determined under our reference 17-08634/1-7:
approximated to 200 g/L
The 1-octanol solubility of the test item was determined under our reference
17-08634/1-8: 159.0 ± 0.493 g/L (standard deviation)
logPow = solubility of test item in n-octanol / solubility of test item in water
Pow = 159 g/l / 200 g/l = 0.795
logPow = - 0.10
The partition coefficient of the test item was calculated from the individual solubilities in n-octanol and water at 20 °C, respectively. The log Pow value can be reported as log Pow= - 0.10.
Study Results
Based on the similar chemical structure of calcium isostearate and calcium stearate the water solubility of 0.0007 mg/l (calcium stearate) is considered relevant to assess the water solubility of calcium isostearate.
The partition coefficient of the test item is calculated from the individual solubilities of calcium stearate in water and the test item caclium isostearate in n-octanol, respectively.
The water solubility of calcium stearate was determined to 0.0007 mg/l.
The 1-octanol solubility of the test item calcium isostearate was determined to: 159.0 ± 0.493 g/L (standard deviation).
logPow = solubility of test item in n-octanol / solubility of test item in water
Pow = 159000 mg/l / 0.0007 mg/l = 227142857.14
calculated logPow = 8.36
The partition coefficient of the test item was calculated from the individual solubilities in n-octanol and water at 20 °C, respectively. The log Pow value can be estimated at 8.36.
Description of key information
The partition coefficient of the test item was calculated from the individual solubilities in n-octanol and water (read across substance calcium stearate) at 20 °C, respectively. The log Pow value can be reported as log Pow = 8.36.
Key value for chemical safety assessment
- Log Kow (Log Pow):
- -0.1
- at the temperature of:
- 20 °C
Additional information
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