7-acetamido-4-hydroxy-3-[[4-[[2-(sulphooxy)ethyl]sulphonyl]phenyl]azo]naphthalene-2-sulphonic acid, sodium salt

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Key result

Water solubility:

247.9 g/L

Temp.:

20 °C

pH:

4.3 - 4.4

Conclusions:

Interpretation of results (migrated information): very soluble (> 10000 mg/L)
The water solubility of the test item Reactive Orange 72-78 at a temperature of 20 °C was determined to be 248 g/L

Executive summary:

The water solubility c_S of the test item was determined according to the following guidelines:

EuropeanCommission Regulation (EC) No. 440/2008, A.6. Water solubility; flask method

and OECD test guideline OECD 105 (1995) Water solubility.

In a preliminary test, the water solubility was estimated. In a stepwise procedure, different volumes of distilled water are added at room temperature to a defined amount of the test item. After each addition of an amount of water, the mixture is treated with ultrasound and visually checked for any undissolved particles. According to the preliminary visual estimation the water solubility is in the range of 214 – 1070 g/l. Referring to the guideline the flask method was be applied.

According to the stirrability test about 8 g test item were dissolved in 13 g water resulting in a concentration of approx.. 600 gL in the main testl. The batches were stirred for different times at 30 °C (experiment A for 24 h, experiment B for 48 h, experiment C for 72 h) in tightly closed flasks. After equilibration (further stirring for 24 h at 20 °C) aliquots of the mixtures were taken and centrifuged (30 minutes with 15000 rpm at 20 °C). Aliquots of the aqueous phases were taken, filtrated through double HPLC-filters (0.2 µm) and diluted from 0.1 to 25 ml withdistilled water. This solution was again diluted from 1 ml to 25ml withdistilled water. A sample of 0.1 ml of this solution was diluted to 1 ml with the starting eluent.The pH values of the saturated solutions were determined.The concentration of the test item was determined by HPLC.

The water solubility c_Sof the test item Reactive Orange 72-78 at a temperature of 20 °C was determined to be (without correction for the purity):

c_S 248 g/l     (RSD = 7.3 %)

Description of key information

Water solubility 248 g/L

Key value for chemical safety assessment

Water solubility:

248 g/L

at the temperature of:

20 °C

Additional information

The water solubility c_S of the test item was determined according to the following guidelines:

European Commission Regulation (EC) No. 440/2008, A.6. Water solubility; flask method

and OECD test guideline OECD 105 (1995) Water solubility.

The water solubility c_S of the test itemReactive Orange 72-78at a temperature of 20 °C was determined to be (without correction for the purity):

c_S 248 g/l     (RSD = 7.3 %)