Soybean meal, protein extn. residue

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

04 January 2018 to 30 March 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Version / remarks:

1995

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Version / remarks:

2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Key result

Water solubility:

0.406 g/L

Conc. based on:

other: TOC

Loading of aqueous phase:

1 g/L

Incubation duration:

72 h

Temp.:

20 °C

pH:

>= 5.8 - <= 6

Key result

Water solubility:

4.28 g/L

Conc. based on:

other: TOC

Loading of aqueous phase:

10 g/L

Incubation duration:

72 h

Temp.:

20 °C

pH:

>= 5.2 - <= 5.8

Details on results:

RESULTS
Samples 1, 3 and 5 (Loading rate: 1 g/L): Overall concentration: 0.406 gTOC/L at 20.0 ± 0.5 ºC
Samples 2, 4 and 6 (Loading rate: 10 g/L): Overall concentration: 4.28 gTOC/L at 20.0 ± 0.5 ºC

DISCUSSION
- As the test material is a complex mixture, testing was performed using the flask method (as recommended for mixtures).
- On completion of the equilibration period, Samples 1, 3 and 5 were opaque, pale off-yellow solutions and Samples 2, 4 and 6 were opaque, off-yellow solutions. The solutions were decanted, avoiding excess test material prior to filtration. After filtration, Samples 1, 3 and 5 were slightly translucent, off-white solutions and Samples 2, 4 and 6 were opaque, off-yellow solutions.
- For each loading rate, the three individual water solubility results were within ± 15 % of the mean, thus satisfying the criteria specified in the guidelines.
- It is clear from the results that the water solubility of the test material shows loading rate dependency. Also, as approximately 42 % of the test material dissolved at both loading rates, it can be presumed that the saturation concentration may be much higher than 4.3 g/L at loading rates higher than 10 g/L.

Table 2: The Concentration (g/L) of Total Organic Carbon in the Sample Solutions

Sample Number	Time Shaken at ~30 °C (hours)	Concentration (gTOC/L)	Solution pH
1	72	0.416	6.0
2	72	3.80	5.2
3	48	0.387	5.8
4	48	4.56	5.7
5	24	0.414	5.8
6	24	4.48	5.8

 

Table 3: Results

Nominal Loading Rate (g/L)	Overall Concentration (gTOC/L)	Solution pH
1.0	0.406	5.8-6.0
10	4.28	5.2-5.8

Conclusions:

Under the conditions of this study, the water solubility of the test material at 20.0 ± 0.5 °C (as total dissolved carbon) was determined at two loading rates. At 1.0 g/L nominal loading rate the overall concentration was 0.406 gTOC/L and at 10 g/L nominal loading rate the overall concentration was 4.28 gTOC/L.

Executive summary:

The water solubility of the test material was investigated in accordance with the standardised guidelines OECD 105 and EU Method A.6, under GLP conditions.

As the test material is a complex mixture, testing was performed using the flask method (as recommended for mixtures).

For each loading rate, the three individual water solubility results were within ± 15 % of the mean, thus satisfying the criteria specified in the guidelines.

It is clear from the results that the water solubility of the test material shows loading rate dependency. Also, as approximately 42 % of the test material dissolved at both loading rates, it can be presumed that the saturation concentration may be much higher than 4.3 g/L at loading rates higher than 10 g/L.

Under the conditions of this study, the water solubility of the test material at 20.0 ± 0.5 °C (as total dissolved carbon) was determined at two loading rates. At 1.0 g/L nominal loading rate the overall concentration was 0.406 gTOC/L and at 10 g/L nominal loading rate the overall concentration was 4.28 gTOC/L.

Description of key information

Under the conditions of this study, the water solubility of the test material at 20.0 ± 0.5 °C (as total dissolved carbon) was determined at two loading rates. At 1.0 g/L nominal loading rate the overall concentration was 0.406 gTOC/L and at 10 g/L nominal loading rate the overall concentration was 4.28 gTOC/L.

Additional information

The water solubility of the test material was investigated in accordance with the standardised guidelines OECD 105 and EU Method A.6, under GLP conditions. The study was awarded a reliability score of 1 in accordance with the criteria set forth by Klimisch et al. (1997).

As the test material is a complex mixture, testing was performed using the flask method (as recommended for mixtures).

For each loading rate, the three individual water solubility results were within ± 15 % of the mean, thus satisfying the criteria specified in the guidelines.

It is clear from the results that the water solubility of the test material shows loading rate dependency. Also, as approximately 42 % of the test material dissolved at both loading rates, it can be presumed that the saturation concentration may be much higher than 4.3 g/L at loading rates higher than 10 g/L.

Under the conditions of this study, the water solubility of the test material at 20.0 ± 0.5 °C (as total dissolved carbon) was determined at two loading rates. At 1.0 g/L nominal loading rate the overall concentration was 0.406 gTOC/L and at 10 g/L nominal loading rate the overall concentration was 4.28 gTOC/L.