Disodium 7-benzamido-4-hydroxy-3-[[4-[(4-sulphonatophenyl)azo]phenyl]azo]naphthalene-2-sulphonate

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

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:

1991

Report date:

1991

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

Existing study well reported and performed under GLP.

Test material

Test material information

Constituent 1

Reference substance name:

Disodium 7-benzamido-4-hydroxy-3-[[4-[(4-sulphonatophenyl)azo]phenyl]azo]naphthalene-2-sulphonate

EC Number:

220-028-9

EC Name:

Disodium 7-benzamido-4-hydroxy-3-[[4-[(4-sulphonatophenyl)azo]phenyl]azo]naphthalene-2-sulphonate

Cas Number:

2610-11-9

Molecular formula:

C29H21N5O8S2.2Na

IUPAC Name:

disodium 7-benzamido-4-hydroxy-3-[(1E)-2-{4-[(1E)-2-(4-sulfonatophenyl)diazen-1-yl]phenyl}diazen-1-yl]naphthalene-2-sulfonate

Test material form:

solid: particulate/powder

In vivo test system

Test animals

Species:

guinea pig

Strain:

Himalayan

Sex:

male/female

Details on test animals and environmental conditions:

TEST ANIMALS- Source: BRL Biological Research laboratory Ltd- number of animals: 30 males / 6 females- Age at study initiation: 5 weeks- Weight at study initiation: Control and test group: 281-333 g Pretest:286-307 g- Housing: Individually in Makrolon type-3 cages with standard softwood bedding - Diet : Pelleted standard Kliba 342, Batch 63/91 guinea pig breeding/ maintenance diet, ad libitum.- Water: tap water , ad libitum. Once weekly additional supply of ascorbic acid (1 g/l) via the drinking water. - Acclimation period: One week under test conditions after veterinary examination.ENVIRONMENTAL CONDITIONS- Temperature (°C):22 ± 3°C- Humidity (%):40-70 % - Photoperiod : 12 hours artificial fluorescent light/12 hours dark, music/light period.

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

intradermal

Vehicle:

other: for induction: physiological saline; for epidermal: vaselina album

Induction 2

Concentration / amount:

5% for intradermal injenction5, 10, 15 and 25% for epidermal application The highest non-irritating test article concentration used for challenge application was 15%.

Challenge

Challenge 1

Route:

epicutaneous, occlusive

Vehicle:

other: for induction: physiological saline; for epidermal: vaselina album

Challenge 2

Concentration / amount:

5% for intradermal injenction5, 10, 15 and 25% for epidermal application The highest non-irritating test article concentration used for challenge application was 15%.

No. of animals per dose:

Main study induction: Control 10 females / Test Group: 20 femalesMain study challenge: Control 10 females / Test Group: 20 females

Details on study design:

MAIN STUDYA. INDUCTION EXPOSURE: injection- Test groups: 20 females- Control group: 10 females- Site: An area of dorsal skin from the scapular region (approximately 6 x 8 cm) was clipped free of hair. Three pairs of intradermal injections (0.1 ml/site) were made at the border of a 4 x 6 cm area in the clipped region- Concentrations: 5% with physiological saline, 5% by emulsion in a 50:50 mixture of Freund's colplete adjuvant and physiological salineINDUCTION EXPOSURE: epidermal application, one week after the injections- Exposure period: 48 h- Test groups: 20 females- Control group: 10 females- Site: (6 x 8 cm)- Type of coverage: filter paper was saturated with the test article and placed over the injection sites of the test animais. The patch was covered by aluminum foil and firmly secured by an elastic plaster wrapped around the trunk of the animal and secured with impervious adhesive tape.- Concentrations: 25 % in vaseline albumB. CHALLENGE EXPOSURE: The test and control guinea-pigs were challenged two weeks after the epidermal induction application.- Exposure period: approximately 24 hours later- Test groups: 20 females- Control group: 10 females- Site:hair was clipped and shaved from a 5 x 5 cm area on the left and right flank of each guinea-pig.- Type of coverage: Two patches (2 x 2 cm) of filter paper- Concentrations: 15% in vaseline album - Evaluation : 24, 48 hrsOTHER OBSERVATION:Mortality/Viability: dailyBody Weights:At acclimatization start, start of application and end of test.Symptoms (local systemic): dailyNecropsy: noAll animals were killed at the end of the test period with an intraperitoneal injection of pentobarbital (> 800 mg/kg) and discarded.

Positive control substance(s):

yes

Remarks:

Formaldheyde solution

Results and discussion

Positive control results:

8 guinea pigs in a group of 10 animals showed positive response to the formaldehyde solution.

In vivo (non-LLNA)

Results

Results 1

Reading:

1st reading

Hours after challenge:

28

Group:

test chemical

No. with + reactions:

0

Total no. in group:

20

Clinical observations:

No systemic symptoms were observed.

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 28.0. Group: test group. Dose level: 0. No with. + reactions: 0.0. Total no. in groups: 20.0. Clinical observations: No systemic symptoms were observed..

Results 2

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

No. with + reactions:

0

Total no. in group:

20

Clinical observations:

No systemic symptoms were obseved.

Remarks on result:

other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 0. No with. + reactions: 0.0. Total no. in groups: 20.0. Clinical observations: No systemic symptoms were obseved. .

Results 3

Reading:

1st reading

Group:

negative control

Remarks on result:

no indication of skin sensitisation

Results 4

Reading:

1st reading

Group:

positive control

Remarks on result:

positive indication of skin sensitisation

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

According to EEC (European Economie Community) and CLP classification criteria described in guidelines 83/467, September 16, 1983, the tested substance Direct Red 81 is not a sensitizer.

Executive summary:

The purpose of this skin sensitization study was to assess the allergenic potential of Direct Red 81 when administered to the skin of albino guinea pigs following OECD 406, Maximization-Test of B. Magnusson and A.M. Kligman (1969).

Ten animals (10 females) were treated with the vehicle alone (vaseline album) and 20 animals (20 females) were treated with the test article.

Due to the unequivocal findings observed after the first challenge, no second challenge was performed.