Registration Dossier

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 guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 105 (Water Solubility)
Version / remarks:
Jul. 1995
Deviations:
no
Qualifier:
according to
Guideline:
EU Method A.6 (Water Solubility)
Version / remarks:
Jan. 2014
Deviations:
no
GLP compliance:
yes (incl. certificate)
Type of method:
other: slow stir method

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Type:
Constituent
Type:
Constituent
Test material form:
liquid: viscous

Results and discussion

Water solubilityopen allclose all
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:
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.