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Administrative data

Key value for chemical safety assessment

Additional information

There are no data available for Kaolin, calcined regarding genetic toxicity. However there are data available for structural analogue substances for this endpoint.

In vitro

In the Ames test using five mutant strains (TA 97a, TA 98, TA100, TA 102 and TA1535), the related substance silicic acid, aluminium salt was found to be not mutagenic with or without metabolic activation (Paulus, 2010, RL2).

The related substance silicic acid, aluminium sodium salt did not show mutagenic activity in a mammalian chromosome aberration test in human embryonic lung cells (Wi-38) without metabolic activation (Litton Bionetics, 1974, RL2). Amorphous Silica is also negative in HGPRT assay in Chinese hamster ovary cells with and without metabolic activation (Harbell et al., 1990, RL2). Silica, amorphous, fumed and cryst.-free was also negative in a DNA repair system, an UDS test, in primary rat hepatocytes (Curren, 1989, RL2).

In vivo

Synthetic amorphous silica did not lead to an increase in chromosomal aberrations in bone-marrow cells from orally treated rats (Litton Bionetics, 1974, RL2). Also dominant lethal assays conducted in rats did not produce significant adverse effects on reproductive performance parameters after exposure of male rats to synthetic amorphous silica (Litton Bionetics, 1974, RL2).

Following a repeated dose inhalation exposure (13 weeks) of rats to a mean dust concentration of 50 mg/m³ Aerosil 200, alveolar type-II cells were isolated from the broncho-alveolar lavage fluid (BAL) and subjected to the HPRT gene-mutation assayin vitro. There was no increase in 6TG-resistant mutants compared to controls (Johnston et al., 2000, RL2).

Short description of key information:
Based on the negative results of the related substance silicic acid, aluminium salt in the S. typhimurium Ames test and all tested synthetic amorphous silica (structural analogues) in the additional mammalian in vitro and in vivo studies, no mutagenic potential is expected from exposure to Kaolin, calcined.

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

No need for classification according to DSD (67/548/EEC) or CLP (1272/2008/EC) as the Ames test with the related substance silicic acid, aluminium salt and all in vitro and in vivo studies consistently demonstrate negative results for all tested structurally related compounds.