Sodium 4-[(2-hydroxy-1-naphthyl)azo]benzenesulphonate

Genetic toxicity: in vivo

Administrative data

Endpoint:

in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus

Remarks:

Type of genotoxicity: gene mutation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

23 July 2002 - 19 August 2003

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference

Reference Type:

secondary source

Title:

Unnamed

Year:

2003

Report date:

2011

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)

Deviations:

not specified

GLP compliance:

yes

Type of assay:

micronucleus assay

Test material

Test material information

Constituent 1

Reference substance name:

Sodium 4-[(2-hydroxy-1-naphthyl)azo]benzenesulphonate

EC Number:

211-199-0

EC Name:

Sodium 4-[(2-hydroxy-1-naphthyl)azo]benzenesulphonate

Cas Number:

633-96-5

Molecular formula:

C16H12N2O4S.Na

IUPAC Name:

sodium;4-[(2E)-2-(2-oxonaphthalen-1-ylidene)hydrazinyl]benzenesulfonate

Test animals

Species:

mouse

Strain:

NMRI

Sex:

male/female

Details on test animals or test system and environmental conditions:

No data

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

deionised water

Doses / concentrations

Doses / concentrations 1

Remarks:

Doses / Concentrations:
0
Basis:
nominal in water

Doses / concentrations 2

Remarks:

Doses / Concentrations:
500 mg/kg bw
Basis:
nominal in water

Doses / concentrations 3

Remarks:

Doses / Concentrations:
1000 mg/kg bw
Basis:
nominal in diet

Doses / concentrations 4

Remarks:

Doses / Concentrations:
2000 mg/kg bw
Basis:
nominal in diet

No. of animals per sex per dose:

5 mice / sex / Group

Control animals:

yes, concurrent vehicle

Results and discussion

Test results

Sex:

male/female

Genotoxicity:

negative

Toxicity:

no effects

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Any other information on results incl. tables

In the pre-experiment on acute toxicity with an exposure of 2000 mg/kg bw D&C Orange 4 exclusively a ruffled fur was found up to 4 h after administration. In the main experiment reduction of spontaneous activity, eyelid closure and ruffled fur were found at 2000 mg/kg

bw up to 6 or 24 h (ruffled fur only).

Treatment with D&C Orange 4 did not result in a decreased PCE/NCE ratios compared to the untreated controls indicating that D&C Orange 4 had no cytotoxic properties in the bone marrow.

However, the quantitative analysis of the test item in the plasma of the treated animals showed significant amounts of D&C Orange 4 after 1 h. This level dropped after 4 h.

Biologically relevant or statistically significant increases in the number of micronucleated PCEs compared to the concurrent vehicle controls were not found at any dose tested, neither 24 nor 48 h after treatment and neither for males nor for females.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information): negative
In conclusion, it can be stated that during the study described and under the experimental conditions reported, the test article did not induce micronuclei as determined by the micronucleus test with bone marrow cells of the mouse. Therefore, Acid Orange 7 is considered to be non-mutagenic in this micronucleus assay.

Executive summary:

Under the experimental conditions used D&C Orange 4 did not induce a biologically relevant increase in the number of PCEs with micronuclei in bone marrow cells of treated mice and, consequently Acid Orange 7 is not genotoxic (clastogenic and/or aneugenic) in bone marrow cells of mice.