4,4'-methylenedi-o-toluidine

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: Meets generally accepted scientific standards, well documented and acceptable for assessment (restriction: only three tester strains were used)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1977

Report date:

1978

Materials and methods

Principles of method if other than guideline:

According to: Ames BN, McCann J, Yamasaki E (1975): Methods for detecting carcinogens and mutagens with the Salmonella/ mammalian-microsome mutagenicity test, Mutat Res 31: 47-364, with minor modifications

GLP compliance:

no

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

4,4'-methylenedi-o-toluidine

EC Number:

212-658-8

EC Name:

4,4'-methylenedi-o-toluidine

Cas Number:

838-88-0

Molecular formula:

C15H18N2

IUPAC Name:

4-[(4-amino-3-methylphenyl)methyl]-2-methylaniline

Details on test material:

- Name of test material: Toluidinbase/ 3,3´-Dimethyl-4,4´-diaminodiphenylmethane
- Physical state: solid, crystalline
- Analytical purity: 99%

Method

Species / strain

Species / strain 1

Species / strain / cell type:

other: Salmonella typhimurium TA 98, TA 100, TA 1537

Species / strain 2

Species / strain / cell type:

S. typhimurium TA 100

Metabolic activation:

with and without

Metabolic activation system:

Liver S-9 mix from male rats treated with Aroclor 1254

Test concentrations with justification for top dose:

3.15 - 3000 µg/plate

Vehicle / solvent:

DMSO

Controls

Negative solvent / vehicle controls:

yes

Positive controls:

yes

Positive control substance:

other: see details on test system

Details on test system and experimental conditions:

Standard platetest: The test compound dissolved in DMSO, bacterial suspension and top agar were mixed in the absence and presence of Aroclor 1254, phenobarbital or ß-naphthoflavone induced male rat liver S9-mix and poured into a minimal agar containing petri dish. After incubation for 2-3 days in the dark, his+ revertants were counted.
Test concentration without metabolic activation: 0, 31.5, 100, 315, 1000, 3000 µg/plate
Test concentration with metabolic activation: 0, 3.15, 10, 31.5, 100, 315, 1000, 3000 µg/plate
Every single experiment contained positive controls for checking the activity of the metabolizing system and the mutability of the bacteria as well as negative controls.

Positive controls:
Without metabolic activation: N-methyl-N'-nitro-N-nitrosoguanidine and benzo(a)pyrene-4,5-oxide for all strains
With metabolic activation: 3-methylcholanthrene, benzo(a)pyrene and 2-aminoanthracene for all strains

Evaluation criteria:

Positive results
- doubling of the spontaneous mutation rate (control)
- dose-response relationship
- reproducibility of the result

Results and discussion

Test results

Test results 1

Species / strain:

other: S. typhimurium TA 100, TA 1537, TA 98

Metabolic activation:

without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity, but tested up to precipitating concentrations

Remarks:

precipitation which was observed in concentrations >= 1000 µg/plate

Vehicle controls validity:

valid

Positive controls validity:

valid

Test results 2

Species / strain:

other: S. typhimurium TA 100, TA 1537

Metabolic activation:

with

Genotoxicity:

positive

Cytotoxicity / choice of top concentrations:

other: precipitation was observed in concentrations >= 1000 µg/plate; cytotoxicity was obseved in TA100 in the same concentrations in one experiment.

Vehicle controls validity:

valid

Positive controls validity:

valid

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

Standard plate test (31.5 - 3000 µg/plate)
Strain	Metabolic activation system	mean revertants in Controls	maximum revertant factor*	dose dependency	Assessment
TA 98	no	23	1.0	no	negative
	yes (Aroclor 1254)	50	5.4	yes	positive
TA 100	no	150	1.3	no	negative
	yes (Aroclor 1254) 1st run	139	20.9	yes	positive
	yes (Aroclor 1254) 2nd run	145	17.0	yes	positive
	yes (Phenobarbital)	163	22.7	yes	positive
	yes (b-Naphthaflavone)	140	12.0	yes	positive
TA 1537	no	11	1.0	no	negative
	yes (Aroclor 1254)	22	1.1	no	negative
* in non-precipitating concentrations