Registration Dossier

Administrative data

Endpoint:
skin sensitisation: in vivo (non-LLNA)
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP compliant guideline study, availabe as unpublished report, no restrictions in design and/or reporting therefore adequate for assessment

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1990
Report Date:
1990

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 406 (Skin Sensitisation)
GLP compliance:
yes
Type of study:
guinea pig maximisation test

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): MBDA
- Purity: >99%
- Physical state: liquid, yellowish
- Storage: room temperature; exclusion of oxygen

In vivo test system

Test animals

Species:
guinea pig
Strain:
Pirbright-Hartley
Sex:
female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Lippische Versuchtierzucht, Hagemann GmbH & Co. KG, D-4923 Extertal 1, FRG
- Weight at study initiation: 286 - 328 g
- Housing: 5 animals per cage, Makrolon type IV cage; Granulat Type 3/4 (staubfrei) SSNIFF bedding
- Diet: ad libitum, Kliba 341.4 mm (Kaninchen-Meerschweinchen-Haltungsdiät)
- Water: ad libitum, tap water (about 2 g of ascorbic acid per 10 L water was added)
- Acclimation period: at least 8 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 - 24
- Humidity (%): 30 - 70
- Air: fully air-conditioned rooms
- Photoperiod (hrs dark / hrs light): 12/12

Study design: in vivo (non-LLNA)

Inductionopen allclose all
Route:
intradermal and epicutaneous
Vehicle:
olive oil
Concentration / amount:
- Intradermal induction: test substance 2% in olive oil DAB9 resp. in Freund's adjuvant/water (1:1) resp. olive oil DAB9
- Epicutaneous induction: 25% in olive oil DAB9 resp. olive oil DAB9
- 1st challenge: 10% in olive oil DAB9 resp. olive oil DAB9
- 2nd challange: 10% in olive oil DAB9 resp. olive oil DAB9
Challengeopen allclose all
Route:
epicutaneous, occlusive
Vehicle:
olive oil
Concentration / amount:
- Intradermal induction: test substance 2% in olive oil DAB9 resp. in Freund's adjuvant/water (1:1) resp. olive oil DAB9
- Epicutaneous induction: 25% in olive oil DAB9 resp. olive oil DAB9
- 1st challenge: 10% in olive oil DAB9 resp. olive oil DAB9
- 2nd challange: 10% in olive oil DAB9 resp. olive oil DAB9
No. of animals per dose:
- Test substance: 20
- Control: 10
Details on study design:
RANGE FINDING TESTS:
- Amount applied: 2 x 2 cm filter paper strips were applied to the skin of the flanks under an occlusive dressing. The test filter paper strip was soaked in the test substance resp. in the test substance formulation; thus, the animals were exposed to about 0.15 g of the test substance formulation.
- Exposure period: 2 times for 24 hours within a period of 96 hours in order to detect non-specific phenomena that are not caused by a sensitization reaction but could possibly be attributed to a shift in the irritation threshold.
- Site of application: flank, respective on the same area
- Number of test animals: 3 per test concentration
- Readings: 24 and 48 h after the beginning of application

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: 2 (day 0 intradermal injections + day 7 epicutaneous exposure)
- A total of six intradermal injections in groups of two per animal was made. These injections were: A) front row: 2 injections each of 0.1 mL Freund's adjuvant without test substance emulsified with water in a ratio of 1:1, B) middle row: 2 injections each of 0.1 mL of the test substance formulation, C) back row: 2 injections each of 0.1 mL Freund's adjuvant/ water (1 : 1) with test substance.
- Epicutaneous exposure: 2 x 4 cm filter paper strips were applied to the skin of the shoulder under an occlusive dressing .The filter paper strip was soaked in the test substance; thus, the animals were exposed to about 0.3 g of the test substance.
- Exposure period (epicutaneous): 48 hours
- Control group: The animals were given the same injections (A, B, C) but without test substance, only with the formulating agent. For epicutaneous exposure the control groups were treated with the solvent without the test substance.
- Site: shoulder
- Evaluation: 24 h after intradermal injections, and 48 h after epicutaneous exposure.

B. CHALLENGE EXPOSURE
- No. of exposures: 2
- Concentration: non-irritant concentration
- Exposure: 2 x 2 cm filter paper strips were applied to the skin of the flank under an occlusive dressing. The test filter paper strip was soaked in the test substance; thus the animals were exposed to about 0.15 g of the test substance.
- 1st challenge: treatment of the test group and of control group 1 with the test substance formulation. Additionally olive oil DAB9 was applied as a vehicle. Control group 2 only received olive oil DAB9.
- 2nd challenge: treatment of the test group and of control groups 1 and 2 with the test substance formulation. Analogous to the first challenge olive olive oil DAB9 applied as a vehicle.
- Day(s) of challenge: 21 and 28
- Exposure period: 24 h
- Site: intact clipped flank
- Evaluation (hr after challenge): 24, 48 and 72
Challenge controls:
Identical procedure for the induction exposure. The animals were given the same injections (A) front row: 2 injections each of 0.1 mL Freund's adjuvant without test substance emulsified with water in a ratio of 1:1, B) middle row: 2 injections each of 0.1 mL of the test substance formulation, C) back row: 2 injections each of 0.1 mL Freund's adjuvant/ water (1 : 1) with test substance) but without test subsance. For epicutaneous exposures the animals were treated with only the solvent.

In the challenge exposure control group 1 received the test substance formulation in both the 1st and 2nd challenge. Control group 2 received in the 1st challange only the solvent and in the 2nd challenge the test substance formulation.
Positive control substance(s):
not specified

Results and discussion

In vivo (non-LLNA)

Resultsopen allclose all
Reading:
2nd reading
Hours after challenge:
48
Group:
other: negative control 1
Dose level:
10%
No. with + reactions:
1
Total no. in group:
10
Remarks on result:
other: Reading: 2nd reading. . Hours after challenge: 48.0. Group:
Reading:
2nd reading
Hours after challenge:
48
Group:
other: negative control 1
Dose level:
0%
No. with + reactions:
2
Total no. in group:
10
Remarks on result:
other: Reading: 2nd reading. . Hours after challenge: 48.0. Group:
Reading:
2nd reading
Hours after challenge:
48
Group:
other: negative control 2
Dose level:
10%
Clinical observations:
Not performed
Remarks on result:
other: Reading: 2nd reading. . Hours after challenge: 48.0. Group:
Reading:
2nd reading
Hours after challenge:
48
Group:
other: negative control 2
Dose level:
0%
No. with + reactions:
7
Total no. in group:
10
Remarks on result:
other: Reading: 2nd reading. . Hours after challenge: 48.0. Group:
Reading:
2nd reading
Hours after challenge:
48
Group:
test group
Dose level:
10%
No. with + reactions:
20
Total no. in group:
20
Remarks on result:
other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 10%. No with. + reactions: 20.0. Total no. in groups: 20.0.
Reading:
2nd reading
Hours after challenge:
48
Group:
test group
Dose level:
0%
No. with + reactions:
3
Total no. in group:
20
Remarks on result:
other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 0%. No with. + reactions: 3.0. Total no. in groups: 20.0.
Reading:
rechallenge
Hours after challenge:
48
Group:
other: negative control 1
Dose level:
10%
No. with + reactions:
8
Total no. in group:
10
Remarks on result:
other: Reading: rechallenge. . Hours after challenge: 48.0. Group:
Reading:
rechallenge
Hours after challenge:
48
Group:
other: negative control 1
Dose level:
0%
No. with + reactions:
0
Total no. in group:
10
Remarks on result:
other: Reading: rechallenge. . Hours after challenge: 48.0. Group:
Reading:
rechallenge
Hours after challenge:
48
Group:
other: negative control 2
Dose level:
10%
No. with + reactions:
0
Total no. in group:
10
Remarks on result:
other: Reading: rechallenge. . Hours after challenge: 48.0. Group:
Reading:
rechallenge
Hours after challenge:
48
Group:
other: negative control 2
Dose level:
0%
No. with + reactions:
0
Total no. in group:
10
Remarks on result:
other: Reading: rechallenge. . Hours after challenge: 48.0. Group:
Reading:
rechallenge
Hours after challenge:
24
Group:
test group
Dose level:
10%
No. with + reactions:
20
Total no. in group:
20
Remarks on result:
other: Reading: rechallenge. . Hours after challenge: 24.0. Group: test group. Dose level: 10%. No with. + reactions: 20.0. Total no. in groups: 20.0.
Reading:
rechallenge
Hours after challenge:
48
Group:
test group
Dose level:
0%
No. with + reactions:
3
Total no. in group:
20
Remarks on result:
other: Reading: rechallenge. . Hours after challenge: 48.0. Group: test group. Dose level: 0%. No with. + reactions: 3.0. Total no. in groups: 20.0.

Any other information on results incl. tables

- After intradermal induction distinct erythema and edema were observed at the injection sites of the control animals and the test animals, at which only Freund's adjuvant/aquadest. (1 : 1) was applied. Injection of test substance preparation in olive oil DAB9 resp. in Freund's adjuvant/aquadest. (1 :1) caused distinct erythema and edema in the test animals. The control animals injected with olive oil DAB9 (vehicle) showed distinct erythema.

 

- After epicutaneous induction incrustation, partially open (caused by the intradermal induction) in addition to severe erythema and distinct edema could be observed in the test animals. The animals of control group one and two which were applied with olive oil DA89 (vehicle) exhibited incrustation, partially open (caused by the intradermal induction) in addition to distinct erythema and edema.

 

- After the first challenge (48 hours after the beginning of application) with the 10% test substance preparation in olive oil DAB9 4 of 20 test animals showed very severe erythema. 3 of them also showed slight edema and one of them distinct edema. In 7 of 20 test animals severe erythema in addition to slight edema could be observed. Distinct erythema was observed in 7 of 20 test animals. One of them also showed slight edema. 2 of 20 test animals exhibited slight erythema. One of 10 animals of control group 1 showed slight erythema.

 

- After the first challenge (48 hours after the beginning of application) olive oil DA89 which was applied as a vehicle caused slight erythema in 1 of 10 animals of control group 1. Another animal of control group 1 showed distinct erythema. 5 of 10 animals of control group 2 exhibited slight erythema and 2 animals distinct erythema. 2 of 20 animals of the test group showed slight erythema and 1 animal distinct erythema.

 

- The second challenge (48 hours after the beginning of application) with the 10% test substance preparation in olive oil DAB9 caused distinct erythema in addition to superficial scabbing in 4 of 20 test animals. 2 of them also showed slight edema. In 14 of 20 test animals distinct erythema could be observed, 5 of them also exhibited scaling. 2 of 20 test animals showed slight erythema. 5 of 10 animals of control group 1 exhibited distinct erythema, 2 of them also showed scaling. One of these 2 animals also exhibited slight edema. In 3 of 10 animals of control group 1 slight erythema could be observed. Control group 2 did not show any skin reactions.

 

- After the second challenge (48 hours after the beginning of application) olive oil DAB9 which was applied as a vehicle caused slight erythema in 3 of 20 test animals, one of them also showed scaling. One animal of control group 1 exhibited scaling. The animals of control group 2 did not show any skin reactions

Applicant's summary and conclusion

Interpretation of results:
sensitising
Remarks:
Migrated information
Conclusions:
The test item is considered to be a skin sensitizer under the test conditions of this study.
Executive summary:

The substance was tested for its sensitizing effect on the skin of the Pirtbright-Hartley guinea pig in a GLP-compliant OECD 406 guideline study, based on the method of Magnusson and Klingman. 20 animals per test group and 10 animals per control group received six intradermal injections of 2% on day 0 and one epicutaneous application of 25% on day 7, during the induction exposure. On day 21 all animals from the test group and animals from control group 1 were challenged epicutaneously with 10% test substance solution. On day 28 all animals (test group, control group 1 and control group 2) were challenged epicutaneously with 10% test substance solution. Relatively more animals from the test group suffered from moderate to severe erythema and/or edema, after both challenges, compared to animals from the control groups. It was therefore concluded that the substance is a skin sensitizer.