ytterbia stabilised yttrium disilicate

Water solubility

Administrative data

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

02 November 2017 - 12 April 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

column elution method

Test material

Test material information

Constituent 1

Reference substance name:

ytterbia stabilised yttrium disilicate

Molecular formula:

Yb2-xYxSi2O7

IUPAC Name:

ytterbia stabilised yttrium disilicate

Test material form:

solid: particulate/powder

Details on test material:

Name: ytterbium doped yttrium disilicate
Physical state: solid
Appearance: white powder
Further information on test material confidential.

Results and discussion

Water solubility

Water solubility 1

Key result

Water solubility:

0.9 mg/L

Conc. based on:

element (dissolved fraction)

Remarks:

yttrium

Temp.:

20 °C

pH:

6

Remarks on result:

other: Expressed as yttrium content in water; mean of flow rates 12.5 mL/h and 6.25 mL/h.

Water solubility 2

Key result

Water solubility:

0.05 mg/L

Conc. based on:

element (dissolved fraction)

Remarks:

ytterbium

Temp.:

20 °C

pH:

6

Remarks on result:

other: Expressed as ytterbium content in water; mean of flow rates 12.5 mL/h and 6.25 mL/h.

Details on results:

Yttrium:
Results were validated by:
- Linearity validation: The analysis showed a good linearity of the method (r > 0.99).
- Accuracy validation: Results in dilution mixture showed a good accuracy which indicates acceptable data (recoveries ranged between 70 and 110%).
- Repeatability validation: The results indicated a good precision of the data (RSD < 20%).
- Specificity: The intensity (CPS) of blank samples measured was negligible.
- Limit of quantification: 0.1 mg Y/L
- Limit of detection: 0.02 mg Y/L

Ytterbium:
Results were validated by:
- Linearity validation: The analysis showed a good linearity of the method (r > 0.99).
- Accuracy validation: Results in dilution mixture showed a good accuracy which indicates acceptable data (recoveries ranged between 70 and 110%).
- Repeatability validation: The results indicated a good precision of the data (RSD < 20%).
- Specificity: The intensity (CPS) of blank samples measured was negligible.
- Limit of quantification: 0.03 mg Yb/L
- Limit of detection: 0.01 mg Yb/L

Any other information on results incl. tables

Results of the preliminary test with milliQ water and at pH 6 were:

Amount of test item weighed (g)	0.1	0.1	0.1	0.1	0.1	0.1	0.01
Volume of water added (mL)	0.1	0.5	1	2	10	100	1000
Solubility (yes/no)	No	No	No	No	No	No	No (after > 96 h of agitation of the test solution)

Results of the main test

	Solubility expressed as Yttrium content in water (mg/L)	Solubility expressed as Ytterbium content in water (mg/L)	Mean pH measured	Temperature (°C)
Test 0 (flow 25 mL/h)	Mean 0.2 mg/L - not stable	Mean 0.01 mg/L - not stable	6	20
Test 1 (flow 12.5 mL/h)	0.9	0.03	6	20
Test 2 (flow 12.5 mL/h)	0.8	0.04	6	20
Mean (Test 1 and Test 2)	0.9	0.04	6	20
Test 3 (flow 6.25 mL/h)	0.8	0.05	6	20
Mean (12.5 mL/h and 6.25 mL/h)	0.9	0.05	6	20

 

Applicant's summary and conclusion

Conclusions:

During the water solubility test with ytterbium doped yttrium disilicate, performed according to the column elution method, the water solubility of yttrium from the test substance was determined to be 0.9 mg Y/L, and that of ytterbium was determined to be 0.05 mg Yb/L. The test was performed at 20°C and the average pH measured during the test was 6.