Registration Dossier

Toxicological information

Genetic toxicity: in vitro

Currently viewing:

Administrative data

Endpoint:
in vitro gene mutation study in bacteria
Remarks:
Type of genotoxicity: gene mutation
Type of information:
experimental study
Adequacy of study:
weight of evidence
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
Acceptable, well documented publication which meets basic scientific principles (neither Escherichia coli strain WP2 uvrA pKM101a nor S. typhimurium strain TA102 were employed in this study for the detection of oxidising mutagens and cross-linking agents)

Data source

Reference
Reference Type:
publication
Title:
Mutagenicity evaluation of nitroanilines and nitroaminophenols in Salmonella typhimurium.
Author:
Shahin MM
Year:
1985
Bibliographic source:
International Journal of Cosmetic Science 7: 277-289

Materials and methods

Principles of method if other than guideline:
The test procedure described by Maron and Ames (1983) was followed.

Maron & Ames (1983). Mutation Res. 113: 173-215
GLP compliance:
no
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): o-Nitroaniline
- Analytical purity: > 98 % (HPLC, TLC)

Method

Target gene:
His +/-
Species / strain
Species / strain / cell type:
other: TA1535, TA1537, TA1538, TA98, TA100
Metabolic activation:
with and without
Metabolic activation system:
S9 mix prepared from liver microsomal fractions from male Wistar rats pretreated with 500 mg/kg bw Aroclor 1254
Test concentrations with justification for top dose:
5-1000 µg/plate (8 concentrations)
Vehicle / solvent:
DMSO
Controls
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
other: 1,2-diamono-4-nitrobenzene, 2-aminoanthracene
Details on test system and experimental conditions:
METHOD OF APPLICATION: in agar (plate incorporation)

NUMBER OF REPLICATIONS: 3 plates/dose; two separate experiments

Evaluation criteria:
A dose-dependent two-fold increase in the number of revertants per plate was used as the criterion for genetic activity of the compounds tested. A 2.5-fold increase over the spontaneous level, even without clear evidence of dose-dependence, was also considered to be an indication of genetic activity if found in repeated experiments.

Results and discussion

Test results
Species / strain:
other: TA1535, TA1537, TA1538, TA98, TA100
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
no cytotoxicity
Vehicle controls validity:
valid
Untreated negative 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

Compound/control

TA1535

TA100

TA1537

TA1538

TA98

 

- S9

+ S9

- S9

+ S9

- S9

+ S9

- S9

+ S9

- S9

+ S9

 

Revertants/nmol

o-nitroaniline

-

-

-

-

-

-

-

-

-

-

 

 

 

 

 

 

 

 

 

 

 

 

Revertant colonies/plate**

Negative control

18.5

17.5

166.0

159.5

25.0

34.0

30.0

45.0

47.5

61.5

Solvent control

17.5

18.0

146.0

147.5

28.5

36.0

31.0

45.5

47.0

57.0

1,2-diamino-4-nitrobenzene

40.5

34.5

639.0

400.0

194.0

67.0

1990.0

1794.0

3018.5

2311.5

2-aminoanthracene

21.0

220.0

168.0

1649.0

23.5

258.0

29.5

1133.0

40.0

2050.0

* All values were determined from the linear portion of the dose response curves.

** Average of at least 30 independent controls.

The data reported in the present publication clearly show that not all compounds with a nitro group in their structure are genetically active. The three nitroanilines (ortho, meta, para) are isomers. The mutagenic properties of some members of this group therefore seem to have structural requirements beyond simple membership in this class of chemicals. Rather mutagenicity or non-mutagenicity seems to depend on the position of the electron donating amino (NH2) and hydroxy (OH) groups and the electron accepting nitro (NO2)group in the structure of these compounds. The authors have found o-nitroaniline not to be mutagenic in Salmonella typhimurium. Moreover, the addition of a hydroxy group to m-nitroaniline either diminished its mutagenic activity (e.g., 2-nitro-6-aminophenol, 2-nitro-4-aminophenol) or altered its activity (e.g., 4-nitro-2-aminophenol).

Applicant's summary and conclusion