3,3'-dichlorobenzidine dihydrochloride

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: Acceptable, well documented study report which meets basic scientific principles

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1978

Report date:

1978

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

only 4 strains used

GLP compliance:

no

Remarks:

prior to GLP implementation

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

3,3'-dichlorobenzidine dihydrochloride

EC Number:

210-323-0

EC Name:

3,3'-dichlorobenzidine dihydrochloride

Cas Number:

612-83-9

Molecular formula:

C12H10Cl2N2.2ClH

IUPAC Name:

3,3'-dichloro-[1,1'-biphenyl]-4,4'-diamine dihydrochloride

Details on test material:

- Name of test material (as cited in study report): TK 11 482 HCl

Method

Target gene:

his

Species / strain

Species / strain / cell type:

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

Metabolic activation:

with and without

Metabolic activation system:

Aroclor induced rat liver S9-mix

Test concentrations with justification for top dose:

5, 15, 45, 135, 405 µg/0.1 mL

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO

Controls

Controls 1

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: N-methyl-N-nitro-N-nitrosoguanidine

Remarks:

for strain 1535, without S9-mix

Controls 2

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

9-aminoacridine

Remarks:

for TA1537, without S9-mix

Controls 3

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: daunoblastin

Remarks:

for TA98, wtihout S9-mix

Controls 4

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

4-nitroquinoline-N-oxide

Remarks:

for TA100, without S9-mix

Controls 5

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

cyclophosphamide

Remarks:

for TA1535, with S9-mix

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)


DURATION
- Exposure duration: 48 hours
- Expression time (cells in growth medium): 48 hours


NUMBER OF REPLICATIONS: 3 plates per strain and per group, 2 plates per positive control


DETERMINATION OF CYTOTOXICITY
- Method: relative total growth

Evaluation criteria:

The test substance was considered to be non-mutagenic if the colony count in relation to the negative control was not doubled at any concentration.

Statistics:

arithmetic mean

Results and discussion

Test results

Test results 1

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

positive

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Test results 2

Species / strain:

S. typhimurium, other: TA100, TA1537

Metabolic activation:

with

Genotoxicity:

positive

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

at the highest concentration (405 µg/0.1mL)

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Test results 3

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Test results 4

Species / strain:

S. typhimurium, other: TA100, TA1537

Metabolic activation:

without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

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'.

Any other information on results incl. tables

Results from experiments without metabolic activation:

		S. typhimurium
	µg/0.1mL	TA98	TA100	TA1535	TA1537
test substance	control	42	239	21	14
	5	65	230	21	7
	15	118	221	22	7
	45	183	261	27	11
	135	321	244	28	12
	405	58	265	17	11
Daunoblastin	control	25
	2.5	81
	5	202
	10	261
4-Nitroquinoline-N-oxide	control		334
	0.0625		656
	0.125		852
	0.25		1077
N-methyl-N'-nitro-N-nitroso-guanidine	control			19
	3			142
	5			856
9(5) aminoacridine hydrochloride	control				8
	25				52
	50				343
	100				>1350

Results from experiments with metabolic activation:

	µg/0.1mL	S. typhimurium
		TA98	TA100	TA1535	TA1537
test substance	control	44	201	13	20
	5	185	238	11	14
	15	1273	317	5	30
	45	>2130	254	8	60
	135	>2700	427	10	203
	405	>3100	818	9	172
Cyclosphosphamide	control			23
	100			118
	250			301

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
positive

TK 11 482 HCl exerted a clear-cut mutagenic action in this test system.