p,p'-dinitrobibenzyl

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 compliant study using a different set of tester strains as compared to actual guidelines

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1982

Report date:

1982

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Principles of method if other than guideline:

a different set of tester strains was used as compared to actual guidelines

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

1,1'-ethane-1,2-diylbis(4-nitrobenzene)

EC Number:

212-001-5

Cas Number:

736-30-1

Molecular formula:

C14H12N2O4

IUPAC Name:

1,1'-ethane-1,2-diylbis(4-nitrobenzene)

Method

Species / strain

Species / strain / cell type:

other: S. typhimurium TA 1535, TA 1537, TA 1538, TA 98 and TA 100

Metabolic activation:

with and without

Metabolic activation system:

Aroclor 1254 induced rat liver S9 mix

Test concentrations with justification for top dose:

1.0, 10.0, 100.0, 500.0, 1000.0, 2500.0, 5000.0, 10000.0 µg per plate with and without metabolic activation

Vehicle / solvent:

DMSO

Controls

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

9-aminoacridine

2-nitrofluorene

sodium azide

other: 2-Anthramine

Evaluation criteria:

(1) Strains TA-1535, TA-1537 and TA-1538
If the solvent control value is within the normal range, a test
material producing a positive response equal to or above three times the solvent
control value is considered mutagenic.

(2) Strains TA-98 and TA-l00
If the solvent control value is within the normal range, a test
material producing a positive response equal to or above twice the solvent
control value is considered mutagenic.

Statistics:

not required

Results and discussion

Test results

Species / strain:

other: S. typhimurium TA 1535, TA 1537, TA 1538, TA 98 and TA 100

Metabolic activation:

with and without

Genotoxicity:

positive

Remarks:

in TA-1538, TA-98 and TA-l00 with and without metabolic activation

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'.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
positive

The test material exhibited genetic activity with the strains TA-1538, TA-98 and TA-100 with and without metabolic activation and was therefore considered to be mutagenic under these test conditions.

Executive summary:

The test compound was examined for mutagenic activity in a series of in vitro microbial assays employing Salmonella indicator organisms (TA 98, TA100, TA 1535, TA 1537, TA 1538). The compound was tested in the absence and in the presence of liver microsomal enzyme preparations from Aroclor-induced rats.

A negative control consisting of the solvent used for preparing the stock solutions and subsequent dilutions of the test material and specific positive compounds were also assayed concurrently with the test material. The negative control data was used as the basis for evaluating the results obtained with the test material.

Doses were selected from a preliminary study conducted with the test material at 14 doses of 1.22 µg to 10,000 µg per plate using the strain TA-100.

In the preliminary toxicity study, the test material did not exhibit toxicity to the indicator strain at any of the doses tested as evidenced by the presence of the background lawn on the minimal plates. As such, the mutagenicity assays were conducted at 8 doses of 1.0 µg to 10,000.0 µg per plate.

The test conducted on the test material in the absence of a metabolic activation system was positive with strains TA-1538, TA-98 and TA-100.

The test conducted on the test material in the presence of a rat liver activation system was positive with strains TA-1538, TA-98 and TA-100.