Sodium 4-(2-hydroxynaphth-1-ylazo)-3-methylbenzenesulphonate

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

other: experimental result on similar substance

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study well documented, meets generally accepted scientific principles, acceptable for assessment.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1980

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: Hazardous Substances Regulation, US Federal Hazardous Labelling Act. Sect. 191-11 (February 1965)

Deviations:

not specified

GLP compliance:

not specified

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

Test material form:

solid: particulate/powder

Test animals

Species:

rabbit

Strain:

Californian

Details on test animals or test system and environmental conditions:

Age: 12-16 weeks
Body weight: average 2.16 kg for males and 2.24 for females.
Source: Hylyne Commercial rabbits Lt
Acclimation: 1 week
Caged singly in an experimental room mainteined at a temperature of 16°C and with a humidity of 50-70%.
Animals were exposed to artificial light for 10 hours daily from 8-18 hours.
Commercial diet, Labsure Christopher Hill Group, was fed ad libitum.
Sterile filtered water was available at all the times.

Test system

Type of coverage:

occlusive

Preparation of test site:

shaved

Vehicle:

water

Controls:

not specified

Amount / concentration applied:

10 g of the test compound was mixed with 12ml of deionised water to make a solution of 20ml.
1 ml of which was applied to each test site on a 2.5cm square gauze pad.
These were couered with aluminium foil secured with "TFanspore" surgical tape. The test sites were then couered by a 6" wide "Coban" self adhesive bandage in order to retain the test substance in close contact with the skin.

Duration of treatment / exposure:

24 hours

Observation period:

72 hours and up to 14 days after treatment

Number of animals:

6, 3 for each sex

Details on study design:

Twenty-four hours prior to the dermal application, the backs of the rabbits were shaved over an area consisting of at least 10%
of the total body surface. Two test sites lateral to the mid line of the back were used on each rabbit. Immediately before the application
of the test compound, the right hand site was abraded with the point of a sterile hypodermic needle. The abrasions were sufficiently deep
to penetrate the stratum corneum but not to damage the dermis. The left hand sit« remained intact.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal: 11,12

Time point:

24/48/72 h

Score:

1

Reversibility:

fully reversible

Results 2

Irritation parameter:

erythema score

Basis:

animal: 13, 15,14 and 16

Time point:

24/48/72 h

Score:

0.66

Reversibility:

fully reversible

Results 3

Irritation parameter:

edema score

Basis:

animal: 11

Time point:

24/48/72 h

Score:

1.66

Reversibility:

fully reversible

Results 4

Irritation parameter:

edema score

Basis:

animal: 15,12 and 14

Time point:

24/48/72 h

Score:

1.33

Reversibility:

fully reversible

Results 5

Irritation parameter:

edema score

Basis:

animal: 13

Time point:

24/48/72 h

Score:

0.66

Reversibility:

fully reversible

Results 6

Irritation parameter:

edema score

Basis:

animal: 16

Time point:

24/48/72 h

Score:

1

Reversibility:

fully reversible

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: OECD GHS

Conclusions:

Based on the test results, the tested item is to be considered as non-irritant to the skin of rabbits.

Executive summary:

The primary irritation score was assessed following the Hazardous Substances Regulation, US Federal Hazardous Labelling Act. Sect. 191-11 (February 1965).

The result show no irritation on rabbit skin therefore Acid Orange 8 is to be considered as non-irritant to skin under CLP classification based on the result on similar substance.