Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

Hydrolysis:

The molecules of the reaction mass ionise under aqueous conditions in the environment to form potassium, aluminium and fluoride ions which will combine to form various inorganic salts and organic complexes. Since hydrolyses changes the chemical form but does not decompose cesium potassium fluoroaluminate, the concept of degradation by hydrolysis is not relevant in the consideration of its environmental fate.

Biodegradation:

The concept of biodegradation does not apply to inorganic substances.

Bioaccumulation:

Due to the dissociation behaviour of multiconstituent aluminium potassium fluoride, its bioaccumulation cannot be assessed. Given its ionic nature, the substance is expected to partition favourably to water rather than organic and fatty media.

Adsorption/desorption:

As cryolite dissociates in water and the risks are assumed to be determined by fluoride, it is more appropriate to assess the adsorption behaviour of fluoride. In a column leaching test, Koc values varying from 603 - 6502 were found for fluoride in 4 different soils, tested at cryolite concentrations varying from 5 - 50 ppm (Dykeman, 1985). As the percentage of fluoride in the molar weight in both substances is practically identical, namely 54% for cryolite and approx. 53% for aluminium potassium fluoride, similar Koc values can be expected for multiconstituent aluminium potassium fluoride and it is considered that aluminium potassium fluoride will show a similar behaviour in soil.The geometric mean of 1498 (log Koc 3.18) will be used in the assessment.