Registration Dossier

Administrative data

Key value for chemical safety assessment

Additional information

The substance aluminium zirconium chloride hydroxide is an inorganic substance, which does not exist as a molecule under physiological conditions. Instead, it would dissociate into inorganic ionic species, of which Al and Zr species are considered the most relevant for human health assessment. Substance specific test data with the substance aluminium zirconium chloride hydroxide are not available for the assessment of genetic toxicity. Instead, read-across is applied from data obtained with other Al and Zr compounds. The dissolution and speciation behaviour of both Al and Zr compounds is complex and - depending on various parameters such as concentrations and pH - often insoluble (=poorly bioavailable) precipitates like oxides and hydroxides can be encountered under physiological conditions. Nevertheless, as a conservative approach, read-across is applied from soluble Al and Zr substances.

Regarding the Al moiety, the registrants for aluminium zirconium chloride hydroxide have obtained the licence to use for studies (all guideline conform and conducted under GLP principles) conducted with basic aluminium chloride (CAS 1327-41-9): a test for bacterial mutation (Ames test, OECD 471), an in-vitro gene mutation study in mammalian cells (mouse lymphoma, OECD 476), and an in-vitro micronucleus assay in human lymphocytes (OECD 487). The substance basic aluminium chloride gave negative test results in all test systems. Thus, “aluminium” is not considered to be of any concern regarding genetic toxicity. Read across is applied in this regard from basic aluminium chloride to aluminium zirconium chloride hydroxide, based on chemical similarity and the common aluminium moiety.

Regarding the Zr moiety, the registrants for aluminium zirconium chloride hydroxide have obtained the licence to use for studies (all guideline conform and conducted under GLP principles) conducted with zirconium acetate (CAS 7585-20-8, EC 231-492-7): a test for bacterial mutation (Ames test, OECD 471), an in-vitro gene mutation study in mammalian cells (mouse lymphoma, OECD 476), and a chromosome aberration test (OECD 473) . The substance zirconium acetate gave negative test results in all test systems. Thus, “zirconium” is not considered to be of any concern regarding genetic toxicity. Read across is applied in this regard from zirconium acetate to aluminium zirconium chloride hydroxide, based on chemical similarity and the common zirconium moiety.

In conclusion, the substance aluminium zirconium chloride hydroxide is considered not to have any mutagenic/genotoxic potential, based on read-across from soluble Al and Zr substances.


Short description of key information:
Read-across - based on the respective metal ions - from the soluble substances basic aluminium chloride and zirconium acetate. Negative results for both read-across substances in all relevant test systems. Conclusion: no genotoxic/mutagenic potential for aluminium zirconium chloride hydroxide.

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

Read-across - based on the respective metal ions - from the soluble substances basic aluminium chloride and zirconium acetate. Negative results for both read-across substances in all relevant test systems. Conclusion: no genotoxic/mutagenic potential for aluminium zirconium chloride hydroxide, thus no hazard classification required.