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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro gene mutation study in mammalian cells
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
Justification for type of information:
The study is well-documented by the publication and thus acceptable for assessment.

Data source

Reference
Reference Type:
publication
Title:
Induction of trifluorothymidine-resistant mutants by metal ions in L5178 Y/TK+/- cells
Author:
Amacher, D.E.; Paillet, S.C.
Year:
1980
Bibliographic source:
Mutat. Res. 78, 279-288

Materials and methods

Principles of method if other than guideline:
Induction of TK mutations in mouse lymphoma cells (L5178Y/TK+/- to TK-/-). Treatment was for 3 hrs in the absence of metabolic activation
GLP compliance:
not specified
Type of assay:
in vitro mammalian cell gene mutation tests using the thymidine kinase gene

Test material

Reference
Name:
Unnamed
Type:
Constituent

Method

Target gene:
thymidine kinase locus
Species / strain
Species / strain / cell type:
mouse lymphoma L5178Y cells
Details on mammalian cell type (if applicable):
soft-agar media containing RPMI-1640, 10% horse serum, no antibiotics, 1mM sodium pyruvate, 0.02% (w/v) Pluronic F-68 and 0.37% Difco Bacto agar
Additional strain / cell type characteristics:
not specified
Metabolic activation:
without
Test concentrations with justification for top dose:
5.69 - 57.11 µg/ml
6 cultures treated with metal compound and 3 solvent controls
Vehicle / solvent:
saline
Controls
Untreated negative controls:
no
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
not specified
Details on test system and experimental conditions:
3 hours at 37°C treatment, following 48 hours at 37°C expression period
incubation for 7 days in TFT containing medium (4µg/mL)

Results and discussion

Test results
Key result
Species / strain:
mouse lymphoma L5178Y cells
Metabolic activation:
without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
cytotoxicity
Vehicle controls validity:
valid
Untreated negative controls validity:
not specified
Positive controls validity:
not specified

Applicant's summary and conclusion

Conclusions:
The test substance cobalt dichloride hexahydrate did not induce gene mutations in mouse lymphoma cells at the given concentrations and under the conditions applied in the test.