Talc (Mg3H2(SiO3)4)

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro cytogenicity / chromosome aberration study in mammalian cells

Remarks:

Type of genotoxicity: chromosome aberration

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference

Reference Type:

publication

Title:

Some in vivo and in vitro studies carried out with talc samples.

Author:

Endo-Capron S, Fleury-Feith J, Nebut M, De Neef R, and Jaurand MC.

Year:

1990

Bibliographic source:

NATO ASI Series, Series G. 1990;21:(Health Related Effects of Phyllosilicates):369-375.

Materials and methods

Test guideline

Test guideline 1

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 473 (In Vitro Mammalian Chromosome Aberration Test)

Test guideline 2

Qualifier:

equivalent or similar to guideline

Guideline:

EU Method B.10 (Mutagenicity - In Vitro Mammalian Chromosome Aberration Test)

Principles of method if other than guideline:

primary screening by the chromosomal aberration test in vitro

GLP compliance:

not specified

Type of assay:

in vitro mammalian cell transformation assay

Test material

Test material information

Constituent 1

Reference substance name:

Talc (Mg3H2(SiO3)4)

EC Number:

238-877-9

EC Name:

Talc (Mg3H2(SiO3)4)

Cas Number:

14807-96-6

Molecular formula:

H2Mg3O12Si4

IUPAC Name:

Talc (Mg3H2(SiO3)4)

Test material form:

solid

Method

Target gene:

rat pleural mesothelial cells (RPMC).

Species / strain

Species / strain / cell type:

mammalian cell line, other: rat pleural mesothelial cells (RPMC)

Details on mammalian cell type (if applicable):

In the SCE assay, RPMC were treated with 0, 2, 5, 10, and 15 μg/cm2 of each talc sample for 48 h.

Additional strain / cell type characteristics:

not specified

Metabolic activation:

without

Test concentrations with justification for top dose:

Two negative reference particle controls, anatase and attapulgite, and the two positive controls reference particles named previously were used, as were the chemical controls mitomycin C in water and K2CrO4 in culture medium.

Vehicle / solvent:

chemical controls mitomycin C in water and K2CrO4 in culture medium.

Controls

Untreated negative controls:

yes

Remarks:

untreated cells

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Positive controls:

yes

Details on test system and experimental conditions:

In the SCE assay, RPMC were treated with 0, 2, 5, 10, and 15 μg/cm2 of each talc sample for 48 h. Two negative reference particle controls, anatase and attapulgite, and the two positive controls reference particles named previously were used, as were the chemical controls mitomycin C in water and K2CrO4 in culture medium.

Evaluation criteria:

Two negative reference particle controls, anatase and attapulgite, and the two positive controls reference particles named previously were used, as were the chemical controls mitomycin C in water and K2CrO4 in culture medium. T

Statistics:

no data

Results and discussion

Test results

Species / strain:

mammalian cell line, other: rat pleural mesothelial cells (RPMC)

Metabolic activation:

without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

not specified

Untreated negative controls validity:

not specified

Positive controls validity:

not specified

Additional information on results:

Exposure of rat pleural mesothelioma cells to 3 talc samples and 3 asbestos fibre samples as a positive control (anatase, chrysotile and crocidolite) led to increased sister chromatid exchange and to increased DNA repair synthesis (UDS) only with the asbestos samples, but not with the talc samples

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Applicant's summary and conclusion

Conclusions:

Interpretation of results: negative

Talc did not cause a statistically significant increase in SCEs and was not clastogenic. The negative particle controls and chemical controls gave expected results; chrysotile and crocidolite statistically significantly increased SCEs in 2/4 and 3/8 experiments, respectively.

Executive summary:

The test substance is non-mutagenic under the given experimental conditions.