Oligomerisation products of plasma treated triglycerides, C16-18 (even numbered) and C18 (unsaturated)

Water solubility

Administrative data

Endpoint:

water solubility

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:

2019

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Version / remarks:

Jul. 1995

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Version / remarks:

Jan. 2014

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

other: slow stir method

Test material

Test material information

Constituent 1

Reference substance name:

vegetable oil mono- and polyunsaturated C16-C22 triglycerides

Molecular formula:

C51H92O6 to C69H128O6

IUPAC Name:

vegetable oil mono- and polyunsaturated C16-C22 triglycerides

Constituent 2

Reference substance name:

dimers of vegetable oil mono- and polyunsaturated C16-C22 triglycerides

Molecular formula:

C102H186O12 to C138H256O12

IUPAC Name:

dimers of vegetable oil mono- and polyunsaturated C16-C22 triglycerides

Constituent 3

Reference substance name:

trimers of vegetable oil mono- and polyunsaturated C16-C22 triglycerides

Molecular formula:

C153H280O18 to C207H388O18

IUPAC Name:

trimers of vegetable oil mono- and polyunsaturated C16-C22 triglycerides

Constituent 4

Reference substance name:

tetramers and higher oligomers of vegetable oil mono- and polyunsaturated C16-C22

Molecular formula:

C204H374O24 and higher oligomers

IUPAC Name:

tetramers and higher oligomers of vegetable oil mono- and polyunsaturated C16-C22

Test material form:

liquid: viscous

Results and discussion

Water solubility

Water solubility 1

Water solubility:

0.33 mg/L

Conc. based on:

test mat. (dissolved fraction)

Loading of aqueous phase:

0.5 g/L

Incubation duration:

3 d

Temp.:

20 °C

pH:

5.85 - 6.16

Water solubility 2

Water solubility:

0.44 mg/L

Conc. based on:

test mat. (dissolved fraction)

Loading of aqueous phase:

10 g/L

Incubation duration:

3 d

Temp.:

20 °C

pH:

5.85 - 6.16

Any other information on results incl. tables

Measurements during equilibration

Day	Temperature [°C]	pH*	Measured Areas	Concentration DOC Mean [mg/L]	Conc. Test item [mg/L]	Difference [%]
1	20.0	5-6	386 390 369	0.27	0.35
2	20.0	5-6	384 351 349	0.25	0.33	-6.6
3	20.5	5-6	351 377 365	0.26	0.33	1.0
3 (blank)	20.0	6	9 0 12	< LOQ	< LOQ

* measured using pH paper

Measurements at plateau

Flask	Temp. [°C]	pH*	Measured Areas	Concentration DOC Mean [mg/L]	Conc. test item [mg/L]
2	20.5	6.16	388 376 357	0.26	0.34
3**	20.5	6.05	0 0 0	< LOQ	< LOQ
4**	20.5	5.96	0 26 5	< LOQ	< LOQ
5	20.5	6.06	478 426 419	0.32	0.42
6	20.5	5.85	457 454 464	0.34	0.44

** a sample preparation error was suspected, therefore the measurement was repeated (see next table).

Measurements at plateau

Flask	Temp. [°C]	pH*	Measured Areas	Concentration DOC Mean [mg/L]	Conc. test item [mg/L]
3	20.0	-	369 353 372	0.23	0.33
4	20.0	-	19 17 4	< LOQ	< LOQ

The repeated measurement of flask 3 confirmed the presumption of a sample preparation error. The repeated measurement of flask 4 confirms the first measurement. Flask 4 was stated as an outlier and was not use in the evaluation.

Conclusion

As solubility was dependent on the nominal concentration, the solubility of the test item in water can be stated as 0.33 mg/L - 0.44 mg/L for the nominal concentration range 0.5 – 10 g/L.

Applicant's summary and conclusion

Conclusions:

The water solubility was found to be dependent on the nominal concentration. Therefore, the solubility of the test item in water can be stated as 0.33 mg/L - 0.44 mg/L for the nominal concentration range 0.5 – 10 g/L.

Executive summary:

The solubility of the test item “Oligomerisation product obtained by plasma treatment of vegetable oil mono- and polyunsaturated C16-C22 triglycerides” in water was determined by measurement of dissolved organic carbon (DOC) concentrations in the filtrated test solutions using a total organic carbon (TOC) analyser.

From solubility pre-tests performed under non-GLP conditions in the ecotoxicological department, the water solubility was estimated to be below 100 mg/L. Therefore, the preliminary test mentioned in the guideline was not performed and a minimum nominal loading rate of 500 mg/L test item was used. As dependency of the water solubility on the amount of the test item added was expected, different loading rates were used in the main test. Because the test item is a liquid with a density lower than water, the slow stirring method was used to prevent the formation of emulsions. Sampling at the bottom of the flasks was performed to avoid carryover of the test item from the surface.

In the main test, six different test item loading rates were chosen to study the effect of the loading rate on the measured water solubility: 500, 1000, 2500, 5000, 7500 and 10000 mg/L. Three flasks (1A – 1C) with the same loading rate (5000 mg/L) were used during the equilibration phase. Seven vessels (flasks blank, 1C (for the sampling point 72 h) and 2 – 6) were put onto the Magnetic stirrer immediately and slow stirring (100 rpm) was started.

After 24 ± 2 h, flask 1B (for the sampling point 48 h) and after 48 ± 2 h, flask 1A (for the sampling point 24 h) were put on the stirrer and all flasks were stirs for further 24 ± 2 h at room temperature. Then, flasks 1A – 1C were removed from the stirrer, tempered at 20.0 ± 0.5 °C, samples were taken, membrane filtered and analysed for DOC via TOC analyser.

No upward tendency in the last three values, the test was finished on day 2. The final measurement was performed as determination from flasks 2 – 6. DOC was measured via TOC analyser in the saturated aqueous solutions. The pH value in the flasks 2 – 6 lay in the range of 5.85 – 6.16.

A slight dependency of the solubility on the amount of the test item (nominal load) was perceived in the flasks 2 – 6.

Based on the measured values, the concentration of the test item in water was stated as

 

0.33 mg/L – 0.44 mg/L at 20.0 ± 0.5 °C

0.33 mg/L – 0.44 10^-3 kg/m³ (SI units)

 

for the nominal concentration range 0.5 – 10 g/L.