Sodium dithionite

Water solubility

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

water solubility

Type of information:

other: Handbook data

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Qualifier:

no guideline followed

Principles of method if other than guideline:

Not applicable - Handbook data

GLP compliance:

not specified

Type of method:

other: no data

Water solubility:

241 000 mg/L

Temp.:

20 °C

Remarks on result:

other: no further information of pH and loading

Details on results:

Handbook data considered to be from a trusted source acc. to "ECHA, Guidance on information requirements and chemical safety assessment – Chapter R.7a: Endpoint specific guidance". However, no pH value was given in the CRC handbook for the water solubility of sodium dithionate.

No pH value was given but data could be regarded as valid according to "ECHA, Guidance on information requirements and chemical safety assessment – Chapter R.7a: Endpoint specific guidance".

Conclusions:

According to the reference, the water solubility of sodium dithionite is 241000 mg/L. In conclusion the test substance is very soluble. No pH was given.

Reference 2

Endpoint:

water solubility

Type of information:

other: Handbook data

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Qualifier:

no guideline followed

Principles of method if other than guideline:

Not applicable - Handbook data

GLP compliance:

no

Type of method:

other: no data

Water solubility:

220 g/L

Temp.:

20 °C

Remarks on result:

other: no pH stated

Details on results:

no data

Conclusions:

Ca. 22 g anhydrous sodium dithionite are soluble in100 g water at 20 °C (approximately 220 g/L).

Reference 3

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

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

Qualifier:

no guideline followed

Principles of method if other than guideline:

Not applicable - Publication

GLP compliance:

no

Type of method:

other: measured in an inert atmosphere

Water solubility:

181.6 g/L

Temp.:

20 °C

Remarks on result:

other: no pH stated

Details on results:

Stable: no
Temperature effects: = 11.06 g Na2S2O4/100 ml solution (~ 110.6 g/l) at -2.8 °C
= 11.86 g Na2S2O4/100 ml solution (~ 118.6 g/l) at 0.0 °C
= 15.55 g Na2S2O4/100 ml solution (~ 155.5 g/l) at 10.0 °C
= 18.61 g Na2S2O4/100 ml solution (~ 186.1 g/l) at 20.0 °C

The result given in gram of solid contained in 100 ml of solution corresponds to ca. 220 g of solid to be dissolved in 1 liter.

Conclusions:

Experimentially derived data, the examination of solubility of sodium dithionite was one of the main purposes of the literature. Sodium dithionite has a water solubility of 18.61 g/100 mL solution (approximately 186.1 g/L) at 20.0 °C.

Description of key information

Sodium dithionite is highly soluble in water. 

Key value for chemical safety assessment

Water solubility:

241 g/L

at the temperature of:

20 °C

Additional information

For the evaluation of this endpoint, data from one handbook (CRC handbook) were used as key information, supported by two further references. The handbook data considered to be from a trusted source acc. to "ECHA, Guidance on information requirements and chemical safety assessment – Chapter R.7a: Endpoint specific guidance" and therefore, the description of sodium dithionite could be regarded as valid. However, no pH value was given.

The supporting data indicate water solubilities of approximately 220 g/L and 186.1 g/L at 20.0 °C. However, no details about the test conditions are given and all results show that sodium dithionite is highly soluble in water at room temperature.