3-acetyl-6-methyl-2H-pyran-2,4(3H)-dione

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Circa 1984

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1984

Materials and methods

Test guideline

Qualifier:

no guideline followed

Version / remarks:

No guideline stated, but tests conducted in a reputable Japanese facility.

Principles of method if other than guideline:

Please see details on test system below.

GLP compliance:

no

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

3-acetyl-6-methyl-2H-pyran-2,4(3H)-dione

EC Number:

208-293-9

EC Name:

3-acetyl-6-methyl-2H-pyran-2,4(3H)-dione

Cas Number:

520-45-6

Molecular formula:

C8H8O4

IUPAC Name:

3-acetyl-6-methyl-2H-pyran-2,4(3H)-dione

Method

Target gene:

Not applicable.

Species / strain

Species / strain / cell type:

other: S. typhimurium strains TA92, TA1535, TA100, TAI537, TA94 and TA98.

Metabolic activation:

with and without

Metabolic activation system:

Rat liver S-9.

Test concentrations with justification for top dose:

Maximum 10 mg/plate.

Vehicle / solvent:

Solvent DMSO, no details on further dilutions.

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

not specified

Positive controls:

not specified

Details on test system and experimental conditions:

Ames Test: Reverse mutation assays using S. typhimurium strains TA92, TA1535, TA100, TAI537, TA94 and TA98 were carried out according to the method of Ames. For some samples, TA2637 was also used. All these test strains were provided by Dr B. N. Ames, University of California, Berkeley, USA. The liver microsome fraction (S-9) was prepared from the liver of Fischer rats pre-treated 5 days before with polychlorinated biphenyls (500mg/kg body weight of Kanechlor KC-400 in olive oil, ip). The reaction mixture (S-9 mix) contained 5 mM-glucose 6-phosphate, 4 nM-NADPH, 4 mM-NADH, 33mM-KC1, 8 mM-MgCI2, 100 mM-phosphate buffer (pH 7.4) and 3.75 ml S-9 (129 mg protein) in a total volume of 12.5 ml. Cells cultured overnight were pre-incubated with both the test sample and the S-9 mix for 20 min at 37°C before plating. Duplicate plates were used for each of six different concentrations of the sample. The number of revertant (his+) colonies was scored after incubation at 37°C for 2 days. The result was considered positive if the number of colonies found was twice the number in the control (exposed to the appropriate solvent or untreated). If no reasonable dose response was detected, additional experiments using different doses or induced mutation frequency assays were performed.

Evaluation criteria:

See details on test system.

Statistics:

Not specified.

Results and discussion

Test results

Key result

Species / strain:

other: S. typhimurium strains TA92, TA1535, TA100, TAI537, TA94 and TA98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

not specified

Applicant's summary and conclusion

Conclusions:

Dehydroacetic acid was not genotoxic in this Ames test.

Executive summary:

In an Ames test, using S. typhimurium strains TA92, TA1535, TA100, TAI537, TA94 and TA98, Dehydroacetic acid, up to a maximum concentration of 10 mg/plate, was found not to be genotoxic.