Trisodium bis[3-[(4,5-dihydro-3-methyl-5-oxo-1-phenyl-1H-pyrazol-4-yl)azo]-2-hydroxy-5-nitrobenzenesulphonato(3-)]chromate(3-)

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

other: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Study period:

August 17, 1994

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

The test was conducted by means of Read Across approach. The reliability of the source study report is 1. Further information was attached at section 13

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1994

Report date:

1994

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Deviations:

no

GLP compliance:

yes

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

A LLNA study has not been conducted because adequate data from guinea pig Maximisation test study are already available.

Test material

Test material information

Constituent 1

Reference substance name:

Acid Orange 142 - Similar Substance 01

IUPAC Name:

Acid Orange 142 - Similar Substance 01

Test material form:

solid: particulate/powder

In vivo test system

Test animals

Species:

guinea pig

Strain:

other: Pirbright White Strain (Tif: DHP)

Sex:

male/female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: CIBA-GEIGY Limited, Animal Production, 4332 Stein / Switzerland
- Weight at study initiation: 338 to 421 g
- Housing: the animals were housed individually in Macrolon cages (Type 3) , assigned to the different groups by means of random numbers generated by the random number generator, identified by individual ear tags,
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3
- Humidity (%): 30 to 70
- Photoperiod (hrs dark / hrs light):12 hours light cycle day.

Study design: in vivo (non-LLNA)

Induction

Route:

intradermal and epicutaneous

Vehicle:

other: physiological saline

Concentration / amount:

Pretests
Intradermal Induction:
5% in physiological saline (w/v).
Epidermal Applications (induction and challenge):
50 % in physiological saline.

Challenge

Route:

epicutaneous, occlusive

Vehicle:

other: physiological saline

Concentration / amount:

Pretests
Intradermal Induction:
5 % in physiological saline (w/v).
Epidermal Applications (induction and challenge):
50 % in physiological saline.

No. of animals per dose:

5 per sex for the test group and 5 of one sex for controls

Details on study design:

RANGE FINDING TESTS:
Intradermal Induction
The concentration for the intradermal injections was selected on account of the solubility of the test article in standard vehicles and its local and systemic tolerability in a pretest. The following concentration of test article has been used for intradermal injection:
5 % in physiological saline (w/v).
Since 5 % of test substance in physiological saline could be injected and was well tolerated, this concentration was used for the intradermal induction.
Epidermal Applications (induction and challenge)
The concentrations for the epidermal applications were selected on account of the primary irritation potential of the test article. The following concentrations of test substance have been examined on separate animals for the determination of the maximum sub irritant concentration :
30 and 50 % in physiological saline.
50 % was the highest possible concentration of the test article in physiological saline. The tested concentrations did not induce erythema reactions.

MAIN STUDY
A. INDUCTION EXPOSURE
DAY 0: INDUCTION, intradermal injections
Three pairs of intradermal injections (0.1 ml per injection) were made simultaneously into the left and right side of the shaved neck of the test and control group animals.
Test group:
- adjuvant/saline mixture 1:1 (v/v)
- 5 % in physiological saline (w/v)
- 5 % in the adjuvant/saline mixture (w/v)
Control group:
- adjuvant/saline mixture 1:1 (v/v)
- adjuvant/saline mixture 1:1 (v/v)
- physiological saline
DAY 8: INDUCTION, epidermal application
The application site of all animals was pretreated with 10% sodium-laurylsulfate (open application) 24 hours prior to the epidermal induction application.
In the test group FAT 20043/D was incorporated in physiological saline and applied on a filterpaper patch to the neck of the animals (patch 2x4 cm; approx. 0.4 g per patch; occluded administration for 48 hours).
The control group was treated with the vehicle only.
Test group:
- 50% FAT 20043/D in physiological saline
Control group:
- physiological saline only

B. CHALLENGE EXPOSURE
The test and control group animals were tested on one flank with FAT 20043/D in physiological saline and on the other flank with the vehicle alone (patch 2x2 cm; approx. 0.2 g per patch; occluded administration for 24 hours).
Test and control group:
- 50% FAT 20043/D in physiological saline
- physiological saline only

Challenge controls:

- physiological saline only

Positive control substance(s):

not specified

Results and discussion

In vivo (non-LLNA)

Results

Results 1

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

50% in physiological saline

No. with + reactions:

1

Total no. in group:

20

Results 2

Reading:

1st reading

Hours after challenge:

48

Group:

test chemical

Dose level:

50% in physiological saline

No. with + reactions:

0

Total no. in group:

20

Any other information on results incl. tables

Number of positive animals per group after occlusive epidermal application:

Control Group		After 24 hours		After 48 hours
Vehicle control		0/10		0/10
Test control		0/10		0/10
Test Group		After 24 hours		After 48 hours
Vehicle control		0/10		0/10
Test control		1/10		0/10

Applicant's summary and conclusion

Interpretation of results:

other: CLP criteria not met

Conclusions:

Not sensitising

Executive summary:

Method

The study was performed to determine the skin sensitisation potential of the test substance in rabbits according to OECD Guideline 406 (Skin Sensitisation).

Observations

Under the experimental conditions employed, 5 % of the animals of the test group showed skin reactions 24 hours after removing the dressings.

Conclusion

Not sensitising.