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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro gene mutation study in bacteria
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:
Mutagenicity of cosmetic ingredients licensed by the European Communities
Author:
Gocke E, King M-T, Eckhardt K, Wild D
Year:
1981
Bibliographic source:
Mutat Res 90, 91-109

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
GLP compliance:
no
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
Dichloromethane was obtained from Merck Co., Darmstadt, Germany. The compound was checked for correct melting point and elementary analysis.

Method

Target gene:
his
Species / strain
Species / strain / cell type:
S. typhimurium, other: TA98, TA100, TA1535, TA1537, TA 1538
Metabolic activation:
with and without
Metabolic activation system:
S9 from Aroclor-pretreated rats
Test concentrations with justification for top dose:
125, 250, 500, and 750 μl in a 9 litre desiccator
Vehicle / solvent:
None
Controls
Untreated negative controls:
yes
Negative solvent / vehicle controls:
no
True negative controls:
no
Positive controls:
no
Details on test system and experimental conditions:
Because of the volatility of the compound the petri dishes were placed in airtight desiccators for 8 h. Substance was tested in Vogel-Bonner medium.
Evaluation criteria:
Not specified.
Statistics:
Not specified.

Results and discussion

Test results
Species / strain:
S. typhimurium, other: TA98, TA100
Metabolic activation:
with and without
Genotoxicity:
positive
Cytotoxicity / choice of top concentrations:
not specified
Vehicle controls validity:
not specified
Untreated negative controls validity:
not specified
Positive controls validity:
not specified
Additional information on results:
The test substance was active in strains TA98 and TA100 with and without metabolic activation. In the figure below , increases up ca. 10-fold above control were noted in both strains. The increase was statistically significant (p<=0.01).

Any other information on results incl. tables

No data in table form were available, but a figure was included instead (see below).

Figure: results of the Ames test. Ordinate: His+ revertants per plate of the indicated strain(s), viz bullet = TA98 and triangle = TA100; abscissa: uL in 9 -L desiccator; closed symbol: in presence of S9 -mix, open symbol: without S9 -mix.

Applicant's summary and conclusion

Conclusions:
The test substance was active in strains TA98 and TA100 with and without metabolic activation.