4'-methoxyacetoacetanilide

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:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Well performed GLP and OECD guideline study. As compared to actual guidelines a differing set of tester strains was used.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1996

Report date:

1996

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Version / remarks:

as valid in 1996

Deviations:

yes

Remarks:

As compared to actual guidelines a differing set of tester strains was used.

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

4'-methoxyacetoacetanilide

EC Number:

226-615-6

EC Name:

4'-methoxyacetoacetanilide

Cas Number:

5437-98-9

Molecular formula:

C11H13NO3

IUPAC Name:

N-[4-(methoxyacetyl)phenyl]acetamide

Method

Species / strain

Species / strain 1

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Species / strain 2

Species / strain / cell type:

S. typhimurium TA 1538

Metabolic activation:

with and without

Metabolic activation system:

Aroclor 1254 induced rat liver preparation and co-factors (S9 mix)

Test concentrations with justification for top dose:

33, 100, 333, 1000, 3333, 10000 µg per plate

Vehicle / solvent:

DMSO

Controls

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracene (2-AAN), sodium azide (NaN3), 9-aminoacridine (9-AA) and 2-nitrofluorene (2-NF)

Details on test system and experimental conditions:

METHOD OF APPLICATION: plate incorporation test

DURATION
- Exposure duration: the plates were inverted and incubated at 37°C for 2 days

NUMBER OF REPLICATIONS: Two independent mutation tests were conducted. Triplicate plates were prepared for each bacterial strain and dose level in both the presence and absence of S9 mix.

DETERMINATION OF CYTOTOXICITY: A toxicity test using strain TA 100 only was performed in the presence and absence of S9 mix

- Method: background lawn of microcolonies, reduction in mutant colony number

Evaluation criteria:

A significant mutagenic response was recorded if there was:

I) for S. typhimurium strains TA 1535, TA 1537, TA 1538 and TA 98, at
least a doubling of the mean concurrent vehicle control values at some
concentration of the test substances and, for S. typhimurium strain
TA 100, a 1.5-fold increase over the control value. If the mean colony
count on the vehicle control plates was less than 10 then a value of 10
was assumed for assessment purposes. In such cases a minimum count of
20 was required before a significant mutagenic response was identified.

II) a dose related response, although at high dose levels this relationship
could be inverted because of, for example, (1) toxicity to the bacteria
generally, (2) specific toxicity to the mutants and (3) inhibition of foreign
compound metabolising enzymes where mutagens require metabolic
activation by the liver.

III) a reproducible effect in independent tests.

Statistics:

mean values and standard deviation were generally calculated from triplicate plate counts

Results and discussion

Test results

Test results 1

Species / strain:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

There was no toxicity to the background lawn of microcolonies, however there was a reduction in mutant colony number at 10000 µg per plate in some tester strains.

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Test results 2

Species / strain:

S. typhimurium TA 1538

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

There was no toxicity to the background lawn of microcolonies, however there was a reduction in mutant colony number at 10000 µg per plate in some tester strains.

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

It was concluded that the test item was not mutagenic to Salmonella typhimurium when tested in dimethylsulphoxide up to a predetermined maximum limit.

Executive summary:

The test item was tested for mutagenic activity in Salmonella typhimurium strains TA 1535, TA 1537, TA 1538, TA 98 and TA 100 at concentrations ranging from 33 to 10000 µg per plate.

 

The tests were conducted on agar plates in the presence and absence of an Aroclor 1254 induced rat liver preparation and co-factors (S9-mix) required for mixed-function oxidase activity.

 

Concurrent positive controls demonstrated the sensitivity of the assay and the metabolising activity of the S9 mix.

 

The results obtained in both experiments were similar. No mutagenic activity was observed in any of the 5 bacterial strains, in either activation condition.

 

No precipitation of the test material was observed.

 

There was no toxicity to the background lawn of microcolonies, however there was a reduction in mutant colony number at 10000 µg per plate.