4,4'-methylenebis(2,6-diisopropylaniline)

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:

March 1986

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1986

Report date:

1986

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

4,4'-methylenebis(2,6-diisopropylaniline)

EC Number:

243-421-7

EC Name:

4,4'-methylenebis(2,6-diisopropylaniline)

Cas Number:

19900-69-7

Molecular formula:

C25 H38 N2

IUPAC Name:

4-{[4-amino-3,5-bis(propan-2-yl)phenyl]methyl}-2,6-bis(propan-2-yl)aniline

Test material form:

solid: compact

Details on test material:

- Name: P 5240
- Analysis date: 28 January 1986
- Storage: Keep container tightly closed. Keep in a dry, cool and well-ventilated place.
- Aggregate state/appearance: solid mass
- Colour: brown

Method

Species / strain

Species / strain / cell type:

S. typhimurium, other: Salm. typhimurium strains TA1535, TA1537, TA1538, TA98 and TA100

Details on mammalian cell type (if applicable):

- Type and identity of media: The strains were obtained from Professor B.N. Ames, University of California, California, USA
- Properly maintained: yes

Metabolic activation:

with and without

Metabolic activation system:

S9-liver fractions of rats treated with Aroclor 1254

Test concentrations with justification for top dose:

- Pretest: 1.6, 8, 40, 200, 1000, 5000 ug/ml & solvent control
- Main test: 8, 40, 200, 1000, 5000 ug/ml & solvent control

Vehicle / solvent:

sterile reagent grade dimethylsulphoxide (DMSO)

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

9-aminoacridine

2-nitrofluorene

sodium azide

other: 2-aminoanthracene

Details on test system and experimental conditions:

METHOD OF APPLICATION:
- in agar (plate incorporation)

DURATION:
- Preincubation period: 24 h

Statistics:

The F-statistic was calculated from an analysis of variance at the same time.

Results and discussion

Test results

Species / strain:

S. typhimurium, other: Salm. typhimurium strains TA1535, TA1537, TA1538, TA98 and TA100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not valid

Positive controls validity:

valid

Additional information on results:

PRECIPITATION:
There was slight compound precipitation at the maximum dose level in some plates, TA1535 in the presence of S-9 gave a slightly reduced background lawn.

RANGE-FINDING/SCREENING STUDIES:
The concentrations used for the rangefinder were 0, 1.6, 8, 40, 200, 1000, and 5000 ug/plate. P5240 was not toxic to the tester strain at the highest concentration, 5000ug/plate and, consequently, a maximum dose level of 5000ug/plate was selected for the mutation experiments.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

All positive controls were found to give revertants in the expected ranges, showing thot the bacteria were as sensitive to known clastogens as expected and that the S-9 used in the study was capable of metabolising an inactive precursor to a genotoxic intermediate. Only one positive F-statistic was seen in this study. This was shown to be caused by a variation between the dosed groups of TA1535 without S-9 in the second experiment. Re-analysis of the data excluding the 1000 ug/plate point, which was low, did not give a positive F-statistic.

Applicant's summary and conclusion

Conclusions:

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

It is concluded that the test item is not mutagenic when tested against 5 strains in the Ames plate incorporation assay.