Reaction products of tetrazotized 5-amino-2-[(E)-2-(4-amino-2-sulfophenyl)ethenyl]benzenesulfonic acid with 6-amino-4-hydroxynaphthalene-2-sulfonic acid and 4-amino-5-hydroxynaphthalene-2,7-disulfonic acid in 2-[bis(2-hydroxyethyl)amino]ethanol

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Principles of method if other than guideline:

To determine the water solubility of the test item, two different methods can be used according to OECD Guideline 105, EC Guideline A.6 and OPPTS Guideline 830.7840:
− The column elution method for solubility < 10-2 g/L.
− The shake flask method for solubility ≥ 10-2 g/L.
In a preliminary test it was found, that a solution of the test item is too chromatic to confirm a sediment in the beaker which is needed to ensure the saturation. In addition to the strong chromaticity the solution gets more viscous with solving more and more of the test item. Therefore the test design of this study varies from the guidelines.
A solution of the test item was prepared up to a viscosity which is barely practicable for determining the viscosity. This is needed for the varying test design. To determine the solubility the carbon content of the test item was determined as well as the total organic carbon content in the test solution. In combination with the determined density of the solution the content of the test item in this barely practicable test solution can be estimated.

GLP compliance:

yes (incl. QA statement)

Type of method:

other: Determination of Total Organic Carbon (TOC) and C,H and N-elemental analysis

Specific details on test material used for the study:

The test item was visually inspected at ambient temperature (23 °C). The colour and the physical state of the test item were described.
Result: Physical state: powder
Colour: black

Water solubility:

> 841.7 g/L

Conc. based on:

test mat.

Temp.:

20 °C

Remarks on result:

other: pH value not reported

Total organic carbon of the test solution:

	Test 1	Test 2
TOC; [mg/L]	68.43	68.702
Dilution factor	1:4932.5	1:5133.3
Result: TOC in the test solution; [g/L]	337.5	352.7

C,H, N-elemental analysis:

	1. measurement	2. measurement	3. measurement
Carbon	40.96%	40.96%	41.0%
Hydrogen	5.891%	6.007%	5.9%
Nitrogen	8.12%	8.23%	8.2%

Calculation of the water solubility in g/L:

With respect to the carbon content of the test item the content of the test item in the primary test solution was calculated.

	Test 1 [g/L]	Test [g/L]	mean value
content	823.24	860.17	841.7 g/L

Conclusions:

The water solubility of Bayscript Blaukomponente TEA-Salz is > 841.7 g/L.

Executive summary:

The water solubility of the substance Bayscript Blaukomponente TEA-Salz in demineralized water was tested at 20°C according to guideline OECD 105. In a preliminary test no saturation was observed in form of a sediment in the beaker. Due to the strong chromaticity and resulting increased viscosity the test design varies from the guideline. The concentration of the test item in the aqueous test solution was therefore determined by TOC (total organic carbon) analysis in combination with C, H and N-elemental analysis. The water solubility was determined to be >841.7 g/L (Currenta 2017).

Description of key information

The water solubility of Bayscript Blaukomponente TEA-Salz was determined to be > 841.7 g/L (Currenta 2017).

Key value for chemical safety assessment

Water solubility:

841.7 g/L

at the temperature of:

20 °C