3-[[4-[(2-chloro-4-nitrophenyl)azo]phenyl]ethylamino]propiononitrile

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

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:

study report

Title:

Unnamed

Year:

1973

Report date:

1973

Materials and methods

Principles of method if other than guideline:

Test carried out according to method given in "Hazardous substances regulations" under the U.S. Fedreal Hazardous Substances Labelling Act Sect. 191.11 (Feb 1965).

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Disperse Red 050

IUPAC Name:

Disperse Red 050

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Age at study initiation: 10 - 16 weeks
- Weight at study initiation: 3.04 kg (M), 2.38 kg (F)
- Housing: singly
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: 1 week

ENVIRONMENTAL CONDITIONS
- Temperature: 20 ± 1 °C
- Humidity: 50 - 70 %
- Photoperiod: 15 h light - 9 h dark

Test system

Type of coverage:

occlusive

Preparation of test site:

shaved

Remarks:

intact and abraded

Vehicle:

water

Controls:

no

Amount / concentration applied:

10 g of the test compound was dissolved in 10 ml water, to make a solution of approximately 15 ml volume. 0.75 ml of the solution was applied to each test site on a 2.5 cm square gauze pad.

Duration of treatment / exposure:

24 h

Observation period:

72 h

Number of animals:

6 (3 M and 3 F)

Details on study design:

TEST SITE
- Area of exposure: 24 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 site remained intact.
- Application: 0.75 ml of the solution was applied to each test site on a 2.5 cm square gauze pad. These were covered with aluminium foil secured with "Sleek"*- adhesive tape. Test sites were then enclosed by a self adhesive bandage, the edges of which were fixed to the skin by strips of "Sleek" in order to retain test substance in close contact with the skin.

REMOVAL OF TEST SUBSTANCE
- Washing: no

OBSERVATION TIME POINTS
After 24 hours, dressing was removed and intact and abraded application sites were assessed for oedema and erythema. A further assessment was made at 72 hours.


SCORING SYSTEM:
Erythema and eschar formation
0 No erythema
1 Slight erythema (barely perceptible)
2 Well defined erythema
3 Moderate to severe erythema
4 Severe erythema (beef red) to slight eschar formation
Oedema formation
0 No oedema
1 Very slight oedema (barely perceptible)
2 Slight oedema (edges of area well defined by definite raising)
3 Moderate oedema (raised approximately 1 mm)
4 Severe oedema (raised more than 1 mm and extending beyond the area of exposure)

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal: #1, #2, #3 ,#4

Time point:

24/48/72 h

Score:

0

Max. score:

0

Remarks on result:

no indication of irritation

Results 2

Irritation parameter:

erythema score

Basis:

animal: #5, #6

Time point:

24/48/72 h

Score:

0.67

Max. score:

1

Reversibility:

fully reversible within: 72 h

Remarks on result:

other:

Remarks:

no scoring at 48 h; 48 h score assumed to be equal to the highest score between 24 and 72 h

Results 3

Irritation parameter:

edema score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

0

Remarks on result:

no indication of irritation

Any other information on results incl. tables

erythema				oedema
intact		abraded		intact		abraded
24 h	72 h	24 h	72 h	24 h	72 h	24 h	72 h
0	0	2	0	0	0	2	0
0	0	0	0	0	0	0	0
0	0	0	0	0	0	0	0
0	0	0	0	0	0	0	0
1	0	1	0	0	0	0	0
1	0	1	0	0	0	0	0

Applicant's summary and conclusion

Interpretation of results:

other: not irritant according to the CLP Regulation (EC 1272/2008)

Conclusions:

Not irritant to the rabbit skin.

Executive summary:

Method

Skin irritation study in 6 rabbits, shaved on left and right flank. Test substance was applied on both flanks (one intact and one abraded) for 24 h under occlusive dressing. Scoring for erythema and oedema formation was done at 24 h and 72 h after start of application.

Results

Mild signs of erythema were noted at 24 h in 2/6 and 3/6 rabbits on intact and abraded skin, respectively. Such signs were no more present at the 72 h observation time point. No signs of oedema were noted.