Sodium [3-hydroxy-4-[(1-hydroxy-8-sulpho-2-naphthyl)azo]naphthalene-1-sulphonato(4-)]chromate(1-)

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation, other

Remarks:

in vivo test

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From February, 14 to April, 21 1994

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study

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 non-LLNA skin sensitisation study does not need to be conducted because adequate data from an in vivo study are available.

Test material

Test material information

Constituent 1

Reference substance name:

Acid Blue 158

IUPAC Name:

Acid Blue 158

In vivo test system

Test animals

Species:

guinea pig

Strain:

Pirbright-Hartley

Sex:

male/female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: CIBA-GEIGY Limited Animal Production
- Weight at study initiation: 339 to 404 g
- Housing: The animals were housed individually in Macrolon cages (Type 3)
- Diet: The animals received ad libitum standard guinea pig pellets NAFAG No. 845, All batches of the diet are assayed for nutritive ingredients and contamination level
- Water: fresh water ad libitum. The drinking water quality fulfilled the critical parameters in the specifications of the "Schweizerisches Lebensmittelbuch" (Edition 1972). The results of the routine chemical examination of water a t source (Grundwasserfassung Stein) as conducted periodically by the water authority (Baudepartement des Kantons Aargau, Abteilung Gewaesserschutz)

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3 °C
- 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: adjuvant and physiological saline mixture

Concentration / amount:

intradermal injections
Test group:
- adjuvant/saline mixture 1:1 (v/v)
- 5% in physiological saline (w/v)
- 5% in the adjuvant/saline mixture (w/v)
epidermal application
Test group:
- 50% in physiological saline approx. 0.4 g per patch
Control group:
- physiological saline only B.

Challenge

No.:

#1

Route:

epicutaneous, occlusive

Vehicle:

physiological saline

Concentration / amount:

30% in physiological saline, approx 0.2 g per patch

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:
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.

PRETEST:
Intradermal Induction
- No. of exposures: one injection
- Concentrations: 5 % in physiological saline (w/v).
Epidermal Applications (induction and challenge)
- No. of exposures: one application
- Concentrations: 30 and 50 % in physiological saline. 50 % was the highest possible concentration of the test article in physiological saline.

MAIN STUDY
INDUCTION EXPOSURE: intradermal injections
- No. of exposures: Three pairs of intradermal injections (0.1 ml per injection)
- Exposure period: DAY 0- Test groups: 5 male and 5 female Guinea pigs
- Control group: 5 male and 5 female Guinea pigs- Site: left and right side of the shaved neck
- Frequency of applications: one
- Test group Concentrations:
adjuvant/saline mixture 1:1 (v/v)
5% in physiological saline (w/v)
5% in the adjuvant/saline mixture (w/v)
- Control group Concentrations:
adjuvant/saline mixture 1:1 (v/v)
physiological saline

INDUCTION EXPOSURE: epidermal application
- Application: The application site of all animals was pre treated with 10% sodium-laurylsulfate (open application) 24 hours prior to the epidermal induction application.
- No. of exposures: one application
- Exposure period: Day 8
- Test groups: 5 male and 5 female Guinea pigs
- Control group: 5 male and 5 female Guinea pigs
- Site: neck
- Frequency of applications: one
- Duration: 48 hours
- Test group Concentrations: 50% in physiological saline approx. 0.4 g per patch
- Control group Concentrations: physiological saline only

CHALLENGE EXPOSURE
- No. of exposures: one
- Day(s) of challenge: Day 21
- Exposure period: 24 hours
- Test groups: 5 male and 5 female Guinea pigs
- Control group: 5 male and 5 female Guinea pigs
- Site: one flank
- Concentrations of Test group: 30% in physiological saline, approx. 0.2 g per patch
- Concentrations of Control group: physiological saline only
- Evaluation (hr after challenge): 24 and 48 hours

Positive control substance(s):

no

Results and discussion

In vivo (non-LLNA)

Results

Results 1

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

30% in physiological saline (0.2 g)

No. with + reactions:

8

Total no. in group:

20

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 30% in physiological saline (0.2 g). No with. + reactions: 8.0. Total no. in groups: 20.0.

Results 2

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

30% in physiological saline (0.2 g)

No. with + reactions:

8

Total no. in group:

20

Remarks on result:

other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 30% in physiological saline (0.2 g). No with. + reactions: 8.0. Total no. in groups: 20.0.

Any other information on results incl. tables

The individual animal body weights were measured at the start and at the end of the test. Body weights were not affected by treatment.

Applicant's summary and conclusion

Interpretation of results:

Category 1B (indication of skin sensitising potential) based on GHS criteria

Conclusions:

Sensitizer

Executive summary:

The study was conducted according to OECD Guideline 406, Guinea Pig Maximisation test. Ten animals (5 male and 5 female) were exposed to test article and 5 Guinea Pig were used as control. During the Intradermal induction the animals were exposed to test article at a concentration of 5 %. During the challenge after 24 and 48 hours 40 % of the treated animals showed a positive reaction to the test item. Based on these positive reaction the test article is considered as sensitizer for Guinea pig.