Calcium titanium trioxide

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From July 12, 2017 to August 03, 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Deviations:

no

GLP compliance:

no

Type of method:

flask method

Key result

Water solubility:

< 0.3 mg/L

Conc. based on:

test mat.

Temp.:

25 °C

pH:

7.59

Remarks on result:

other: pH is calculated mean of Day 1 - 3

Details on results:

Comparison of individual test results for calcium from tests 1, 2, and 3 indicated that there was no increasing solubility over time and the concentrations of all test solutions do not differ by more than 15 %; therefore, the mean results from tests 1, 2, and 3 were reported as the water solubility value to 1 decimal place. Spike sample recoveries lie within acceptable limits (nominal 100 ± 20 %).
No levels of titanium were observed in any test solutions and spike sample recoveries lie within acceptable limits (nominal 100 ± 20 %).
The lack of observable titanium concentration when compared to the calcium concentrations measured suggests that calcium titanate is soluble at <0.1 mg/L in water. The origin of the 5 mg/L calcium measured (rounded to the nearest mg/L) is unknown. Due to the structure of calcium titanate it is not felt that this level is caused by any dissociation from the calcium titanate molecule and is likely due to residual calcium or impurities.
From the titanium result, the water solubility of calcium titanate in solution is estimated based on correction for molecular weight as 0.1 x 135.4 / 47.87 = 0.28 rounded to <0.3 mg/L.
Analysis of test solutions by Malvern Zetasizer indicated that the test substance did not appear to be dispersed in the test solutions and that the values reported are indicative of solubilised test substance.

Conclusions:

Calcium titanate has a water solubility of <0.3 mg/L at 25°C.

Executive summary:

A study was undertaken to establish the water solubility of calcium titanate according to the shake flask technique described in OECD Guideline 105 (Water Solubility). No deviation from the protocol was reported. Test item dispersion within the solution was analysed with Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) and by Malvern Zetasizer, rendering a water solubility of <0.3 mg/L for calcium titanate at 25°C (corrected for molecular weight). Calcium titanate did not appear dispersed in the test solution and the reported value is indicative of solubilised test material.

Description of key information

A study was undertaken to establish the water solubility of calcium titanate according to the shake flask technique described in OECD Guideline 105 (Water Solubility). No deviation from the protocol was reported. Test item dispersion within the solution was analysed with Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) and by Malvern Zetasizer, rendering a water solubility of <0.3 mg/L for calcium titanate at 25°C (corrected for molecular weight). Calcium titanate did not appear dispersed in the test solution and the reported value is indicative of solubilised test material.

Key value for chemical safety assessment

Water solubility:

0.3 mg/L

at the temperature of:

25 °C