Octadecanoic acid, C16-18-alkyl esters

Solubility in organic solvents / fat solubility

Administrative data

Endpoint:

solubility in organic solvents / fat solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

15 Feb - 26 Mar 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Cross-reference

Reason / purpose for cross-reference:

reference to other study

Reference

Endpoint:

partition coefficient

Type of information:

calculation (if not (Q)SAR)

Remarks:

Estimation based on solubility on 1-octanol and in water

Adequacy of study:

weight of evidence

Study period:

27 Mar 2018

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

The water solubility used for the estimation of log Pow is below the detection limit of the analytical method. A clear log Pow cannot therefore estimated.

Reason / purpose for cross-reference:

reference to other study

Reason / purpose for cross-reference:

reference to other study

Qualifier:

according to guideline

Guideline:

other: EU Method A.8 - Appendix 1 (Partition Coefficient - Estimation method)

Version / remarks:

May 2008

Qualifier:

according to guideline

Guideline:

other: Guidance on Information Requirements and Chemical Safety Assessment Chapter R.7a: Endpoint specific guidance

Version / remarks:

Version 4.1, October 2015

GLP compliance:

no

Type of method:

estimation method (solubility ratio)

Partition coefficient type:

octanol-water

Type:

log Pow

Partition coefficient:

> 5.76

Temp.:

20 °C

pH:

6.3

Remarks on result:

other: estimated from solubility in water and 1-octanol

Details on results:

Solubility in water and 1-octanol were both performed at 20 °C
pH 6.3 was measured during the water solubility study.

Pow = solubility of test item in 1-octanol / solubility of test item in water

Pow = 2.9 g/L / <5µg/L > 2.9 g/L / 0.000005 g/L = 5.8E5

log Pow > 5.76

 

The partition coefficient of the test item was calculated from the individual solubilities in 1-octanol and water at 20 °C, respectively. The log Pow value can be reported as:

log Pow > 5.76

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: OECD Guideline 105

Version / remarks:

According to ECHA “Guidance on Information Requirements and Chemical Safety Assessment - Chapter R.7a: Endpoint specific guidance” (version 6.0, 2017), table “Table R.7.1-6 Methods for determination of partition coefficient n-octanol/water”, there is no current guideline to measure the solubility in octanol. A test method can be based on the principled of OECD Guideline 105.

Deviations:

yes

Principles of method if other than guideline:

Flask method according to OECD Guideline 105 (water solubility) was adapted for the measurement of n-octanol solubility.

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Octadecanoic acid, C16-18-alkyl esters

EC Number:

298-680-9

EC Name:

Octadecanoic acid, C16-18-alkyl esters

Cas Number:

93820-97-4

Molecular formula:

C36H72O2 C34H68O2

IUPAC Name:

Octadecanoic acid, C16-18 (even numbered)-alkyl esters

Results and discussion

Solubility in organic solvents / fat solubility

Medium:

n-octanol

Solubility:

2.9 g/L

Temp.:

20 °C

Any other information on results incl. tables

The concentrations of the different test solutions were calculated automatically using the equation of the calibration curve. The results are summarised in the table below:

 

Test mixture	Time [h]	Concentration of test item [mg / 10 mL]	Average of test item [mg / 10 mL]*
1	24	2.917
		2.698
		2.675	27.6
2	48	2.998
		2.850
		2.850	29.0
3	72	2.942
		3.086
		3.043	30.2

* with calculation of the dilution factor (1/10)

 

 

These analytical results allow the calculation of the n-octanol solubility of the test item.

 

Test mixture	Time [h]	Average of test item [g/L]	Total average of test item [g/L]
1	24	2.8
2	48	2.9	2.9±0.14
3	72	3.0

 

The n-octanol solubility was determined at 20 °C.

 

 

The test item represents a mixture of different components. The octanol solubility was determined by integrating the entire peak group of the test item in the obtained chromatograms.