2-Isobutyryl-3,N-diphenylacrylamide

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

Study period:

1989-10-05 to 1990-02-22

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: OECD Guideline under GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1990

Report date:

1990

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

The recommended combination of tester strains icludes the use of either E. coli WP2 uvrA, E. coli WP2 uvrA or S. typhimurium TA 102 for the detection of DNA cross-linking activity of the test substance. Neither of this bacterias/strains were used in this

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Reference

Name:

Unnamed

Type:

Constituent

Details on test material:

- Name of test material (as cited in study report): PD 132,408
- Lot No.: 25965X63
- Receipt date: 1989-09-25

Method

Target gene:

strain specific loci for the histidin gene

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:

Leberhomogenat (S9-Mix) von Aroclor 1254-induzierten Ratten.

Test concentrations with justification for top dose:

Concentration range in the main test (with metabolic activation): From 100 to 10000 µg/plate
Concentration range in the main test (without metabolic activation): From 100 to 10000 µg/plate

Vehicle / solvent:

Solvent: DMSO (Dimethylsufoxid)

Details on test system and experimental conditions:

METHOD OF APPLICATION:
- in agar (plate incorporation)

DURATION
- Exposure duration: 48 h (growth arrest by storing at 4+/-2 °C

NUMBER OF REPLICATES:
- Three replicates for each concentration/test compound

DETERMINATION OF CYTOTOXICITY
- Background lawn

Evaluation criteria:

For TA 1535, TA 1537 and TA 1538: Data sets will be judged positive if the increase in mean revertants at the peak of the dose response is equal to or greater than three times the mean vehicle control value.
For TA 98 and TA 100: Data sets will be judged positive if the increase in mean revertants at the peak of the dose response is equal to or greater than two times the mean vehicle control value.
The mutagenicity test was judged to be valid if the following conditions are met:
- Integrity of the tester strain for the respective genetic modifications
- Spontaneous revertants are in a given range
- Culture titers for the plated bacteria were > 0.6x10^9 cells/mL
- The mean of each positive control must exhibit at least a three-fold increase in the number of revertants over the mean value of the respective vehicle control
- A minimum of three non-toxic dose levels

Statistics:

For the three replicates the mean and standard deviation was calculated

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:

no cytotoxicity, but tested up to precipitating concentrations

Remarks:

max. dose 10000 µg/plate

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

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:

no cytotoxicity, but tested up to precipitating concentrations

Remarks:

max. dose 10000 µg/plate

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

Dose range finding studies: Both the preicubation and the plate incorporation method were used. Ten dose levels (10 to 10000 µg/plate) were plated with cultures of tester strain TA 98 and 100 in both presence and absence of microsomal enzymes. Slight cytotoxicity was reported for the highest doese of 10000 µg/plate in absence of microsomal enzymes.

Applicant's summary and conclusion

Conclusions:

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

The tested substance did not induce back mutations at the respective histidine gene loci iof the used tester strains with and without metabolizing enzymes.

Executive summary:

The results of the Salmonella/Mammalian Microsome Mutagenicity Assay indicate that under the conditions of this study the tested substance ( PD 132,408) did not cause a positive response with any of the tester strains (TA 98, TA 100, TA 1535, TA 1537, TA 1538) either in the presence or absence of microsomal enzymes prepared from Aroclor induced rat liver.