Fatty acids, tall-oil, esters with ethylene glycol

Water solubility

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

12 Mar - 04 Apr 2018

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

water solubility below limit of quantification

Reason / purpose for cross-reference:

reference to other study

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

GLP compliance:

no

Type of method:

flask method

Water solubility:

< 0.005 g/L

Temp.:

20 °C

pH:

ca. 5.44

Selectivity

The method started with a GC/MS-SCAN Mode analysis in order to correctly identify the peaks of the chemical marker 9-octadecenoic acid, methyl ester, the other principal component 9,12-octadecadienoic acid, methyl ester and the internal standard Methyl stearate.

The GC/MS-SCAN Mode has proved itself as confirmatory technique.

Specificity

The method proved to be specific; in fact it has been verified that blank, internal standard and matrix solutions do not interfere with the peak of chemical marker.

Linearity

Method Linearity was tested on the chemical marker on 6 different concentration levels from 3.2 mg/L

to 64.3 mg/L corresponding to range 5-100 mg/L on the test sample preparation. All acceptance

criteria (R>0.99 and/or the confidence interval at 95% for the intercept contains zero) were satisfied.

 

Accuracy

Method accuracy was tested on reconstituted samples prepared at two concentration levels for chemical marker (LOQ and 10LOQ concentrations, corresponding to 5 mg/L and 50 mg/L). Six preparations for each concentration level were prepared. The acceptance criterion (Recovery analyte = 80%-100%, and/or the confidence interval at 95% for the recovery contains 100%) proved to be satisfied.

 

Precision

Method precision was evaluated on reconstituted samples as relative standard deviation (RSD%) of the recovery values. The experimental RSD% meet the acceptance criteria.

 

LOD and LOQ

LOD calculated as the chemical marker concentration with S/N ratio of 3 on the working standard solutions at LOQ level described in the Linearity paragraph and on reconstituted sample at 5 mg/L. The LOQ is defined as the concentration at which all acceptance criteria indicated in table 1 of this study are met. The LOQ is the chemical marker concentration at which the S/N ratio is at least 10 and corresponds to the lowest validated level.

LOD calculated: S/N ~ 3, 0.4 mg/L
LOQ calculate: S/N ~10, 1.2 mg/L

LOQ validated: this concentration met all acceptability criteria, 5 mg/L

 

Water solubility test

The aqueous solubility at 20 °C of the test item “Fatty acids, Tall-oil, esters with ethylene glycol “ was reported being < 0.005 g/L, RSD = 9.90%

 

The results from vessels 1 to 3 appeared constant and their RSD% did not differ by more than 15%. For this reason the results of these three first flasks, are averaged.

The data found are however under the validated LOQ value, so the reported content of water solubility (0.0020 g/L) is to be considered an estimate.

The worst case test (with longer equilibration times, see values of vessel 5, after 5 days at 30 °C and 24h at 20 °C ± 0.5 °C) was reported too. Also in this case the value found did not differ significantly and was below the LOQ value.

 

pH determination

The pH determination at 20°C of each test sample “Fatty acids, Tall-oil, esters with ethylene glycol “ was reported.

S1	S2	S3	S4	S5
5.49	5.49	5.37	5.43	5.44

 

 

DEVIATIONS

No deviations were recorded during the study.

 

CONCLUSIONS

The water solubility of test item “FATTY ACIDS, TALL-OIL, ESTERS WITH ETHYLENE GLYCOL” was performed according to “OECD 105 Adopted by the Council on 27th July 1995” and “EC A.6 water solubility” by an GC/MS method. Parameters verified during this analytical method, developed and validated according to SANCO/3029/99 rev.4, were: Specificity, Linearity, Accuracy, Precision and LOD/LOQ.

The method proved to be specific, linear, precise and accurate.

The aqueous solubility at 20 °C proved to be <0.005 g/L.

Reference 2

Endpoint:

water solubility

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Justification for type of information:

1. SOFTWARE
EPI Suite v4.11 Estimation Programs Interface Suite™ for Microsoft® Windows v 4.11. US EPA, United States Environmental Protection Agency, Washington, DC, USA.

2. MODEL (incl. version number)
WSKOWWIN v1.42

3. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL
See “Test material information”

4. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
See attached information on the model provided by the developer. Further information on the OECD criteria as outlined by the applicant is provided below under "Any other information of materials and methods incl. tables"

5. APPLICABILITY DOMAIN
See attached information and information as provided in "Overall remarks, attachments" section.

6. ADEQUACY OF THE RESULT
See assessment of adequacy as outlined in the "Overall remarks, attachments" section.

Qualifier:

according to guideline

Guideline:

other: REACH Guidance on QSARs

Principles of method if other than guideline:

- Software tool(s) used including version: EPI Suite v4.11
- Model(s) used: WSKOWWIN v1.42
The water solubility of organic compounds is estimated starting from the log octanol-water partition coefficient (log Kow). 12 compound classes are identified, associated to correction factors, and used in a multi-linear regression including log Kow and melting point and/or molecular weight. The water solubility is then estimated with one of two possible equations. For more information see ‘attached justification’ and/or 'Any other information on materials and methods incl. tables'.
The datasets used for the model development (1450 molecules) and for the external validation (85 and 817 molecules) are described in the field 'Any other information on materials and methods incl. tables'.
- Model description: see field 'Justification for type of information', 'Attached justification' and 'Any other information on materials and methods incl. tables'
- Justification of QSAR prediction: see field 'Justification for type of information', 'Attached justification' and 'overall remarks'

GLP compliance:

no

Type of method:

other: QSAR

Water solubility:

0 mg/L

Temp.:

25 °C

Remarks on result:

other: QSAR result, no information on pH

Remarks:

Constituent 1

Water solubility:

0 mg/L

Temp.:

25 °C

Remarks on result:

other: QSAR result, no pH

Remarks:

Constituent 2

Water solubility:

0 mg/L

Temp.:

25 °C

Remarks on result:

other: QSAR result, no pH available

Remarks:

Constituent 3

Water solubility:

0 mg/L

Temp.:

25 °C

Remarks on result:

other: QSAR result, no pH available

Remarks:

Constituent 4

Water solubility:

0 mg/L

Temp.:

25 °C

Remarks on result:

other: QSAR result, no pH

Remarks:

Constituent 5

Constituent A

Log Kow used by Water solubility estimates: 15.26 (calculated)

Melting point was not used as descriptor. The appropriate equation was used.

Log S (mol/L) = 0.796 - 0.854 log Kow - 0.00728 MW + Correction

No applicable correction factors.

Constituent B

Log Kow used by Water solubility estimates: 15.05 (calculated)

Melting point was not used as descriptor. The appropriate equation was used.

Log S (mol/L) = 0.796 - 0.854 log Kow - 0.00728 MW + Correction

No applicable correction factors.

Constituent C

Log Kow used by Water solubility estimates: 15.20 (calculated)

Melting point was not used as descriptor. The appropriate equation was used.

Log S (mol/L) = 0.796 - 0.854 log Kow - 0.00728 MW + Correction

No applicable correction factors.

Constituent D

Log Kow used by Water solubility estimates: 16.24 (calculated)

Melting point was not used as descriptor. The appropriate equation was used.

Log S (mol/L) = 0.796 - 0.854 log Kow - 0.00728 MW + Correction

No applicable correction factors.

Constituent E

Log Kow used by Water solubility estimates: 15.48 (calculated)

Melting point was not used as descriptor. The appropriate equation was used.

Log S (mol/L) = 0.796 - 0.854 log Kow - 0.00728 MW + Correction

No applicable correction factors.

Description of key information

< 1 mg/L at 20 °C (QSAR WSKOWWIN v1.42, Episuite v4.11)

Additional information

The water solubility is reported as being < 1 mg/L using a weight of evidence approach based on results found in the water solubility experimental study, QSAR calculations using EPISuite and on a surface tension measurement.

The water solubility experiment reported a water solubility < 5 mg/L (i.e. below the limit of quantification of the analytical method) at 20 °C using a GC-MS method (OECD 105)

QSAR calculations on 5 different main constituents of the UVCB substance all predict a water solubility far below 1 mg/L (range of 1.16E-11 to 2.86E-11 mg/L).

Futhermore, supporting the calculation results, the surface tension experiment reports that when preparing a test solution of just less than 1 mg/L in deionized water, oil drops were seen of the surface of the solution. This indicates that the water solubility of the substance Fatty acids, tall-oil, esters with ethylene glycol is in fact below 1 mg/L.