4-tert-butylcyclohexanone

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Type of genotoxicity: gene mutation

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study with minor deviations

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2002

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.13/14 (Mutagenicity - Reverse Mutation Test Using Bacteria)

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

4-tert-butylcyclohexanone

EC Number:

202-678-5

EC Name:

4-tert-butylcyclohexanone

Cas Number:

98-53-3

Molecular formula:

C10H18O

IUPAC Name:

4-tert-butylcyclohexan-1-one

Method

Species / strain

Species / strain / cell type:

other: S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102

Metabolic activation:

with and without

Metabolic activation system:

Aroclor S9-mix

Test concentrations with justification for top dose:

INCORPORATION TEST:
up to 5000 ug/plate

PREINCUBATION TEST:
up to 1600 ug/tube

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

not specified

Positive controls:

yes

Positive control substance:

sodium azide

Remarks:

Migrated to IUCLID6: and nitrofurantoin, 4-nitro-1,2-phenylene diamine, mitomycin C, cumene hydroperoxide

Details on test system and experimental conditions:

PLATE INCORPORATION TEST:
assessment of bacteriotoxic toxic effects

PREINCUBATION TEST:
preincubation: 20 min at 37°C in a water bath

BOTH TESTS:
test item: 3 plates were used, both with and without S9 mix, for each strain and dose (in experiments without S9 mix buffer was used as replacement; 0.1 ml solvent/plate)
solvent control: an equal number of plates
positive control: three plates per strain

evaluation:
- after an incubation of 48 h at 37°C
- colony count using an automatic counter

Evaluation criteria:

- gross appraisal of background growth on the plates for mutant determination
- mutant count per plate compared to the negative control

Results and discussion

Test results

Species / strain:

other: S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

INCORPORATION TEST:
bacteriotoxic effects started at 1581 ug/plate

PREINCUBATION TEST:
bacteriotoxic effects started at 400 ug/tube

MUTATION:
in both trials with and without S9 mix no biologically relevant increase in mutant count was observed - no evidence of mutagenic activity was found
the positive controls had a marked mutagenic effect

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'. Remarks: TA 1535, TA 1537, TA 98, TA 100 and TA 102

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative with and without metabolic activation

p-tert.-Butylcyclohexanon was considered to be non-mutagenic without and with S9 mix in the plate incorporation as well as in the preincubation modification of the Salmonella/microsome test.

Executive summary:

This study was performed to assess the mutagenicity of p-tert.-butylcyclohexanon in the Salmonella/microsome test with five Salmonella typhimurium LT2 strains.

The results showed that p-tert.-butylcyclohexanon was non-mutagenic without and with S9 mix in the plate incorporation as well as in the preincubation modification of the test.