Trialuminium bismuth hexaoxide

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Water solubility:

>= 0.162 - <= 0.465 mg/L

Conc. based on:

element (dissolved fraction)

Remarks:

Aluminium

Loading of aqueous phase:

115 mg/L

Incubation duration:

>= 24 - <= 72 h

Temp.:

20 °C

pH:

>= 6.7 - <= 6.9

Water solubility:

>= 0.068 - <= 0.119 mg/L

Conc. based on:

element (dissolved fraction)

Remarks:

Bismuth

Loading of aqueous phase:

115 mg/L

Incubation duration:

>= 24 - <= 72 h

Temp.:

20 °C

pH:

>= 6.7 - <= 6.9

Details on results:

On completion of the equilibration period, the samples were observed to be translucent white suspensions containing excess undissolved test item. The solutions were decanted, avoiding excess test item prior to centrifugation. After centrifugation and filtration, the supernatant was taken for analysis. The supernatant wa s visually observed to be clear, colorless and free from un-dissolved test item.

No suitable substance specific analytical method was available for the evaluation of concentrations of the intact test item metal salt in aqueous media. The apparent solubility of the test item was therefore monitored by inductively coupled plasma mass spectroscopy for quantification of the total dissolved Aluminium and Bismuth concentrations of the sample solutions. Reported water solubility values for the test item have been calculated from the elemental composition of the test item as outlined in the certificate of analysis.

The preliminary water solubility test indicated that the column elution method should have been performed as the solubility was less than 10^-2 g/L. However, due to the chemical nature of the test item, it was not possible to use this method; inorganic metal salt test items are not suitable for column elution testing. From the standard solution calibration graphs, the limit of quantitation (LOQ) was considered to be approximately 0.005 mg/L Bismuth and approximately 0.010 mg/L Aluminium in the saturated test item solutions. As all of the individual test solution results were above the LOQ for each element, all of the results were considered to be “> LOQ”, and therefore, valid.

The individual water solubility results were not within ± 15% of the mean for both elements. On review, it was considered that this sample variability was most likely due to the inherent nature of the test item and not due to inaccuracies in the analytical methodologies used. Therefore, a range of water solubility values based on the lowest and highest element concentration in the three samples has been reported.

Conclusions:

The water solubility of the test item was determined at 20.0 ± 0.5 °C, derived from the observed Aluminium and Bismuth concentration of sample solutions.

Description of key information

The water solubility of the test item was determined at 20.0 ± 0.5 °C, derived from the observed Aluminium and Bismuth concentration of sample solutions. The highest value based on the determinations made is used as the key value for chemical safety assessment (based on dissolved Aluminium content).

Key value for chemical safety assessment

Water solubility:

0.465 mg/L

at the temperature of:

20 °C