Dilithium titanate

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2019-03-05 to 2020-01-24

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:

yes (incl. QA statement)

Remarks:

signed, 2016-08-26

Type of method:

flask method

Water solubility:

0.383 mg/L

Conc. based on:

test mat.

Loading of aqueous phase:

100 mg/L

Incubation duration:

>= 192 - <= 552 d

Temp.:

20 °C

pH:

>= 9.7 - <= 10.4

Remarks on result:

other: calculated based on a titanium concentration of 167 µg/L and a purity of 98 %

Water solubility:

167 µg/L

Conc. based on:

element

Remarks:

Ti

Loading of aqueous phase:

100 other: mg test item / L

Incubation duration:

>= 192 - <= 552 h

Temp.:

20 °C

pH:

>= 9.7 - <= 10.4

Details on results:

The validity criteria haven´t been met.

Results of individual determinations and mean value

Flask°	Li [µg/L]	Ti [µg/L]	pH	Stirring duration [h]
A	1838	33	9.7	192
B	1300	16	10.1	216
C	1389	40	10.2	240
Mean	1509	30	-	-
RSD	19.1	41.9	-	-
D	1704	55	10.4	360
E	1966	161	9.4	384
E*	1706	147	10.3	385
F	1961	167	10.4	408
Mean	1790	121	-	-
RSD	8.2	51.8	-	-
G*	1720	48	10.2	504
G	1697	46	7.8	504.5
H	2029	91	10.3	528
I	1783	23	10.3	552
Mean	1844	54	-	-
RSD	8.9	64.3	-	-
Overall mean	1714	68	-	-
Overall RSD	13.9	80.2	-	-

RSD: relative standard deviation in %
° each flask was analysed 6 times (3 different dilution, double analysis)
* samples were taken again since the pH deviated significantly from previous pH
Italic values are not included into the calculations of mean values
grey value is highest determined concentration

The measured concentrations in all flasks of all test points deviate clearly. The RSD of the all 3 weeks lies between 42 and 64 %. Overall the RSD lies at 80 %.

The relative standard deviation between the single determinations is > 15 %. The validity criteria haven ot been met. Additionally, based on the determined Titanium values, the content of Lithium is far elevated and vice versa.

As stated by the Sponsor this effect could result from mainly Lithium containing impurities in the test item which have a higher water solubility. OECD guideline 105 states that residues can have a big influence on the water solubility results.

During manufacture Lithium carbonate and Titanium dioxide are used as starting materials. Lithium carbonate has a very high water solubility (8.4 g/L). Next to Lithium carbonate also TiO (oxidises in water to TiO₂) and TiO₂ are known impurities (see Study No. 2016/0109/01, IUCLID section 4.1 Appearance). TiO₂ has, in contrast to Lithium carbonate, a very low water solutility (≥ 0.024 - ≤ 0.172 µg/L). This impurity therefore was considered to have a neglectable influence on the titanium results. Therefore the highest titanium concentration, representing the highest possible water solubility, was used to determine a water solubility of Lithium titanate.

Since the validity critera haven´t been met, the water solubility was determined using the highest determined Titanium value of all flasks: 167 µg/L.

Therefore, the water solubility of Lithium titanate in demineralized water at 20 °C is determined to be: 0.000383 g/L

Conclusions:

The water solubility of Lithium titanate at 20 °C was determined to be 0.000383 g/L.

Description of key information

The water solubility of Lithium titanate at 20 °C was determined to be 0.383 mg/L.

Key value for chemical safety assessment

Water solubility:

0.383 mg/L

at the temperature of:

20 °C