Tetrasodium enneatitanium icosaoxide hydrate

Adsorption / desorption

Administrative data

Endpoint:

adsorption / desorption: screening

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because the physicochemical properties of the substance indicate that it can be expected to have a low potential for adsorption

Justification for type of information:

JUSTIFICATION FOR DATA WAIVING

In accordance with column 2 of REACH Annex VIII, the adsorption/desorption screening study (required in section 9.3.1) does not need to be conducted if based on the physicochemical properties the substance can be expected to have a low potential for adsorption.

Based on the water solubility test the substance is highly insoluble in water, thus the core (titanate) of the substance is expected to have a negligible adsorption potential. In addition, the core of the substance is by its nature very stable and unreactive. The exchangable sodium ions may be exchanged under favourable conditions, such as high pH and the availability of suitable ions which they could be exchanged for. However, sodium ions are naturally readily available in the soil's water phase. Sodium ions have a low potential for adsorption, due to their physicochemical properties. The substance can therefore be expected to have a low potential for adsoprtion, and the study does not need to be conducted.

Cross-reference

Reason / purpose for cross-reference:

data waiving: supporting information

Reference

Flask method: water solubility <0.51 µg/L at 20 °C (EU Method A6 and OECD 105 with slight deviations, GLP) 

Water solubility:

0.51 µg/L

at the temperature of:

20 °C

During the preliminary study the water solubility of the sodium form test item was estimated to be < 0.005 mg/L. Method A6 Water solubility (440/2008/EC) recommends that the column elution method should be used if the water solubility is < 1x10^-2 g/L. However, since the substance is insoluble in organic solvents, the column elution method could not be applied.

 

Using the flask method, the sample solution signals in the main test with the sodium form were below the limit of detection (LOD = 5.10 x 10^-7 g/L). Similarly, the water solubility of the sodium/hydrogen form was determined to be less than or equal to 7.43 x 10^-6 g/L. The substance is therefore very poorly soluble in water.