Registration Dossier

Diss Factsheets

Administrative data

Link to relevant study record(s)

Reference
Endpoint:
basic toxicokinetics
Type of information:
other: Expert assessment
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: An assessment was conducted based on an examination of the physical and chemical properties of the substance, its composition, and the toxicokinetics behaviour of its constituents.
Objective of study:
toxicokinetics
Qualifier:
no guideline required
Principles of method if other than guideline:
An assessment was conducted based on an examination of the physical and chemical properties of the substance, its composition, and the toxicokinetics behaviour of its constituents.
GLP compliance:
no
Radiolabelling:
no
Type:
absorption
Results:
No absorption is expected by dermal route and inhalation. Limited absorption of the ionic species released by the dissolution of the substance is expected following oral exposure.
Type:
distribution
Results:
Distribution of the absorbed species is expected mainly in bones and muscles.
Type:
metabolism
Results:
Absorbed species are not expected to metabolise.
Metabolites identified:
not specified
Conclusions:
Interpretation of results (migrated information): no bioaccumulation potential based on study results
Considering that the substance cannot be absorbed due to its particle size, will only release a reduced amount of ionic species following oral exposure and that these species will be poorly absorbed, systemic exposure to the registered substance can be considered as inconsequential.
Executive summary:

The absence of specific toxicokinetics data from animal testing means that it is not possible to make firm conclusions concerning the absorption, distribution, metabolism or excretion of the registered substance. However, an assessment of the toxicokinetics behaviour of the species released by the limited dissolution of the substance has been performed in conjunction with an assessment of the available toxicological data.

According to the information available, the substance is not expected to be absorbed following a dermal or inhalation exposure and only some ionic species released by the limited dissolution of the substance will be absorbed following oral exposure. This limited dissolution is due to the strength of the lattice structure of the registered substance.

Components dissolved and identified during water solubility studies were aluminium, silicon, and magnesium, expected to form aluminium hydroxide, silicon dioxide, and magnesium hydroxide after their release by the substance.

Oral aluminium bioavailability in humans from aluminium hydroxide is extremely low. Absorption of silicon dioxide and magnesium oxide are also limited.

Considering that the substance cannot be absorbed due to its particle size, will only release a reduced amount of ionic species following oral exposure and that these species will be poorly absorbed, systemic exposure to the registered substance can be considered as inconsequential.

It is therefore not considered appropriate to perform further animal studies on this substance.

Description of key information

Considering that the substance cannot be absorbed due to its particle size, and will only release a reduced amount of ionic species following oral exposure and that these species will be poorly absorbed, systemic exposure to the registered substance can be considered as inconsequential.

Key value for chemical safety assessment

Bioaccumulation potential:
no bioaccumulation potential

Additional information

The absence of specific toxicokinetics data from animal testing means that it is not possible to make firm conclusions concerning the absorption, distribution, metabolism or excretion of the registered substance. However, an assessment of the toxicokinetics behaviour of the species released by the limited dissolution of the substance has been performed in conjunction with an assessment of the available toxicological data.

According to the information available, the substance is not expected to be absorbed following a dermal or inhalation exposure and only some ionic species released by the limited dissolution of the substance will be absorbed following oral exposure. This limited dissolution is due to the strength of the lattice structure of the registered substance.

Components dissolved and identified during water solubility studies were aluminium, silicon, and magnesium, expected to form aluminium hydroxide, silicon dioxide, and magnesium hydroxide after their release by the substance. Oral aluminium bioavailability in humans from aluminium hydroxide is extremely low. Absorption of silicon dioxide and magnesium oxide are also limited.

Considering that the substance cannot be absorbed due to its particle size, and will only release a reduced amount of ionic species following oral exposure and that these species will be poorly absorbed, systemic exposure to the registered substance can be considered as inconsequential. It is therefore not considered appropriate to perform further animal studies on this substance.

Categories Display