Reaction mass of isomers of disodium amino-(3-carboxylatopropanamido)hexanoate and trisodium 2,6-bis(3-carboxylatopropanamido)hexanoate

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2017-11-15

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Deviations:

yes

Remarks:

Please refer to 'Principles of method if other than guideline'

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Deviations:

yes

Remarks:

Please refer to 'Principles of method if other than guideline'

Qualifier:

according to guideline

Guideline:

EPA OPPTS 830.7840 (Water Solubility)

Deviations:

yes

Remarks:

Please refer to 'Principles of method if other than guideline'

Principles of method if other than guideline:

A miscibility test was carried out to evaluate the solubility of Test Item in water. This procedure deviates from the guideline but is considered scientifically valid.

During a method validation study a solubility pre-test was performed. Based on this experiment the test item was considered to be miscible with water.
The water solubility test based on the OECD 105, EC A.6 and OPPTS 830.7840 guidelines is technically not feasible because no saturated solution could be prepared. For the determination of water solubility a miscibility (homogeneity) test was performed according to the Study Plan. This process deviates from the guideline but is considered scientifically valid.

GLP compliance:

yes (incl. QA statement)

Type of method:

other: miscibility test with visual inspection

Key result

Water solubility:

> 1 000 mg/L

Conc. based on:

test mat.

Temp.:

20 °C

pH:

>= 8.93 - <= 9.59

Details on results:

The test item is miscible with water at room temperature with an estimated solubility of >1000 g/L.

Table 1: Water solubility test

Test Item, (g)	Water, (mL)	Observation	pH value
1.0604	9	clear, homogeneous single-phase liquid	8.94
1.0124	9	clear, homogeneous single-phase liquid	8.97
1.0249	9	clear, homogeneous single-phase liquid	8.93
1.0008	1	clear, homogeneous single-phase liquid	9.17
1.0922	1	clear, homogeneous single-phase liquid	9.21
1.1426	1	clear, homogeneous single-phase liquid	9.20
4.4953	0.5	clear, homogeneous, single-phase, highly viscous liquid	9.52
4.5417	0.5	clear, homogeneous, single-phase, highly viscous liquid	9.59
4.6637	0.5	clear, homogeneous, single-phase, highly viscous liquid	9.54

 

Conclusions:

The water solubility of the test item was determined to be > 1000 mg/L.

Executive summary:

The water solubility was determined according to OECD 105, Regulation (EC) No. 440/2008 method A.6 and OPPTS 830.7840. In a preliminary test no saturated solution of the test item could be prepared, therefore, the standard methods for determination of the water solubility are technically not feasible. Therefore, the water solubility of the test item was determined using the miscibility test with visual detection. The test item was mixed with ultrapure water in rations 1 :1, 1 : 9 and 9 : 1. After sonication and vigorous chaking the solubility was visually detected. The pH of each sample was recorded. The water solubility of the test substance was determined to be > 1000 g/L at ambient temperature (pH 8.9 - 9.6).

Description of key information

The water solubility of the test item was determined to be >1000 mg/L. For further risk assessment a value of 1000 mg/L was used.

Key value for chemical safety assessment

Water solubility:

1 000 mg/L

at the temperature of:

20 °C

Additional information

The water solubility was determined according to OECD 105, Regulation (EC) No. 440/2008 method A.6 and OPPTS 830.7840. In a preliminary test no saturated solution of the test item could be prepared; therefore, the standard methods for determination of the water solubility are technically not feasible. Therefore, the water solubility of the test item was determined using the miscibility test with visual detection. The test item was mixed with ultrapure water in rations 1 :1, 1 : 9 and 9 : 1. After sonication and vigorous chaking the solubility was visually detected. The pH of each sample was recorded. The water solubility of the test substance was determined to be > 1000 g/L at ambient temperature (pH 8.9 - 9.6).

For further risk assessment as a worst case scenariob a value of 1000 mg/L was used.