Sodium 3-[[5-[(diethylamino)sulphonyl]-2-methoxyphenyl]azo]-4-hydroxynaphthalene-1-sulphonate

Genetic toxicity: in vivo

Administrative data

Endpoint:

in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus

Type of information:

other: experimental study on similar substance

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods with acceptable restrictions

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

2015

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:

other: MNT

Test material

Test material information

Constituent 1

Reference substance name:

Disodium 6-hydroxy-5-[(2-methoxy-4-sulphonato-m-tolyl)azo]naphthalene-2-sulphonate

EC Number:

247-368-0

EC Name:

Disodium 6-hydroxy-5-[(2-methoxy-4-sulphonato-m-tolyl)azo]naphthalene-2-sulphonate

Cas Number:

25956-17-6

Molecular formula:

C18H16N2O8S2.2Na

Test animals

Species:

mouse

Strain:

CD-1

Sex:

male

Details on test animals or test system and environmental conditions:

30 mice were used for the experiment (6 mice per treatment, positive control, and negative control group).
Animals were purchased at 6 weeks of age from Charles River Laboratories, Japan and were acclimatized for 7 days before treatments. Food (CRF-1 pellet feed, Oriental Yeast, Japan) and water were provided ad libitum.

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

0.5% carboxymethylcellulose sodium

Details on exposure:

oral gavage

Frequency of treatment:

the test article and the negative control were orally administered daily for 2 days with a 24-h interval using stomach tubes and plastic syringes.
Dosing formulations of thempositive control substance were administered in a single intraperitoneal injection using a disposable syringe fitted with a 25-G needle.

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

500 mg/kg bw/day (nominal)

Doses / concentrations 2

Dose / conc.:

1 000 mg/kg bw/day (nominal)

Doses / concentrations 3

Dose / conc.:

2 000 mg/kg bw/day (nominal)

No. of animals per sex per dose:

30 mice were used in experiments:
6 mice in each of the 3 dose groups
6 mice in the positive control groups
6 mice in the negative control groups.

Control animals:

yes, concurrent vehicle

Positive control(s):

Mitocymin C dissolved in water for injection.

Examinations

Statistics:

Frequencies of MNPCEs in treatment and positive control groups were compared with those in the negative control group using conditional binomial tests (Kastenbaum and Bowman test, uppertailed significance level of 0.05).

Results and discussion

Test results

Sex:

male

Genotoxicity:

negative

Toxicity:

not specified

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

No deaths and no clinical signs of toxicity were observed in any of the treatment groups.
No differences in body weight were observed between control and treatment groups at the end of treatment.
In micronucleus tests, no significant differences in MNPCEs were found between the treated groups and the negative control group.
The frequency of PCEs, which offers an index of the influence of the test substance on bone marrow cells, did not differ between any of the treatment groups and the negative control group.
In contrast, the frequency of MNPCEs in the positive control group was markedly increased in comparison with that in the negative control group.

Applicant's summary and conclusion

Conclusions:

Not mutagen

Executive summary:

The tested substance did not show any mutagenic effect in the in vivo micronucleous test performed according OECD 474.