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Administrative data

Description of key information

Not skin sensitising

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records
Reference
Endpoint:
skin sensitisation: in vivo (non-LLNA)
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Study period:
From April 01st to May 08th, 1998
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
test procedure in accordance with generally accepted scientific standards and described in sufficient detail
Justification for type of information:
Justification for Read Across apporach is detailed in the report attached to the IUCLID section 13
Reason / purpose:
read-across source
Qualifier:
according to
Guideline:
OECD Guideline 406 (Skin Sensitisation)
Version / remarks:
adopted July 17, 1992
GLP compliance:
yes
Type of study:
Buehler test
Justification for non-LLNA method:
Already available study
Species:
guinea pig
Strain:
Pirbright-Hartley
Sex:
female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Harlan Winkelmann, D-33178 Borchen. SPF breeding colony.
- Weight at study initiation: mean 388 g.
- Housing: in fully air-conditioned rooms in macrolon cages (type 4) on soft wood granulate in groups of 5 animals.
- Diet: ssniff® Ms-H (V2233), ad libitum.
- Water: tap water in plastic bottles, ad libitum.
- Acclimation period: at least 7 days.

ENVIRONMENTAL CONDITIONS
- Temperature: 20 ± 3 °C
- Relative humidit: 50 ± 20 %
- Photoperiod: 12 hours daily dark / 12 hrs light.
Route:
epicutaneous, occlusive
Vehicle:
water
Concentration / amount:
0.5 g test item, moistened with 0.25 ml deionized water.
Route:
epicutaneous, occlusive
Vehicle:
water
Concentration / amount:
20 % wlv
No. of animals per dose:
Treatment group: 20
Control group: 10
Determination of the primary non-irritant concentration: 3
Details on study design:
RANGE FINDING TESTS
- Test system: dermal-occlusive test for primary skin irritation.
- Concentrations: 100.0 % test item moistened with deionized water; 20.0 % in deionized water; 4.0 % in deionized water.
- Treated skin: the hair on the flank of the animals was removed mechanically.
- Administration: 0.5 ml g of the test substance preparation was administered to a 2 × 2 cm cellulose patch, which was fixed to the flank and covered occlusively for 6 hours with a bandage and film.
- Exposure period: 24 hours after removal of the patches.
- Scoring system: the treated skin areas were examined for erythema and oedema according to the scale of the EEC-Guideline B.6.

MAIN STUDY
Day 1 to 15 - INDUCTION PHASE
During this test phase, the following procedures were carried out once a week.
- Administration: 0.5 g test item moistened with 0.25 ml deionized water was administered in evenly over a 2 × 2 cm cellulose patch, which was fixed to the front part of the left flank of the animals.
- Dressing: occlusive polyethylene film and a bandage (Fixomull).
- Exposure period: after an exposure period of 6 hours the occlusive bandage was removed and the flank skin washed.
- Control: the 10 control animals were treated analogously with 0.5 ml of the vehicle.

Days 16 to 28 - OBSERVATION
No further animal treatment. Animals under observation (weekends excepted).

Day 29 - CHALLENGE
- Condition: identical conditions for control and treated animals alike.
- Treated skin: the hair of the previously untreated right flank was removed mechanically.
- Concentration: challenge treatment was performed with 20 % test item in deionized water.
- Administration: 0.5 ml of the test concentration was administered to a 2 × 2 cm cellulose patch, which was placed on the hind part of the right flank.
- Dressing: covered with an occlusive bandage.
- Exposure period: exposure was for 6 hours. After removal of the occlusive bandage, any remnants of the substance were carefully washed off with warm water.

Day 30
Macroscopic examination of the skin approx. 24 hours after removal of the patches.

Day 31
Macroscopic examination of the skin approx. 48 hours after removal of the patches.
Terminal body weight determination.

EVALUATION
Erythema and oedema are major clinical indicators of an allergic reaction. The decisive criterion for evaluation of the sensitizing properties of a test substance is the number of sensitized test animals, not the intensity of the dermal reaction.
The substance is considered to be sensitizing if 15 % or more of the animals in the treatment group definitely showed a positive skin reaction and at the same time no irritant effects have emerged in the control group.
Positive control substance(s):
yes
Remarks:
alpha-hexyl cinnamic aldehyde (periodically tested)
Reading:
2nd reading
Hours after challenge:
48
Group:
test group
Dose level:
20.0 % in deionized water
No. with + reactions:
0
Total no. in group:
20
Clinical observations:
none
Remarks on result:
no indication of skin sensitisation
Reading:
2nd reading
Hours after challenge:
48
Group:
negative control
No. with + reactions:
0
Total no. in group:
10
Clinical observations:
none
Remarks on result:
no indication of skin sensitisation
Reading:
2nd reading
Hours after challenge:
48
Group:
positive control
Dose level:
20 % alpha-hexyl cinnamic aldehyde in polyethylene glycol 400
No. with + reactions:
6
Total no. in group:
20
Remarks on result:
positive indication of skin sensitisation

Irritations during the sensitization phase

Discrete or patchy erythema occurred sporadically in the treatment group after the first induction treatment. Discrete or patchy up to moderate and confluent erythema were observed in the treatment group during the sensitization phase after the second and third administration. The animals of the control group showed no signs of irritation during the sensitization phase.

Based on these results, a 20 % preparation of test item in deionized water was selected for the challenge treatment.

Dermal challenge treatment

No signs of irritation were observed in the control and the treatment group 24 and 48 hours after removal of the occlusive bandage.

Body weight gains and clinical signs

The body weight gains of the animals were not impaired. The treated animals showed no clinical signs of intoxication throughout the study. 0

RANGE FINDING TESTS

No signs of irritation occurred after administration of the different test concentrations.

Based on these results, 100 % test item was selected for the sensitization treatments.

Interpretation of results:
other: not classified, according to the CLP Regulation (EC 1272/2008)
Conclusions:
Not skin sensitising
Executive summary:

Testing for the sensitizing properties of test item was performed in female guinea pigs in the Buehler test, according to the OECD guideline 406.

Dermal induction was performed using 100 % test item moistened with deionized water. The control group was exposed to deionized water only. Challenge treatment was carried out with 20 % test item in deionized water. The validity of the test system is confirmed by the periodically conducted positive control test using alpha-hexyl cinnamic aldehyde for the Buehler test.

No signs of irritation were observed in the control and the treatment group 24 and 48 hours after removal of the occlusive bandage. Based on the results of the study, the substance showed no evidence of sensitizing properties.

Conclusion

Not skin sensitising.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not sensitising)
Additional information:

There are no information about the skin sensitization potential of Acid Red 057, thus the available data on structural analogous Similar Substance 02 has been taken into account. The read across approach can be considered as reliable and suitable for the purpose; details and explanations are included in the report attached to the IUCLID section 13.

Testing for the sensitizing properties of Similar Substance 02 was performed in female guinea pigs in a Buheler test, according to OECD guideline 406. Dermal induction was performed using 100 % test item moistened with deionized water. The control group was exposed to deionized water only. Challenge treatment was carried out with 20 % test item in deionized water.

No signs of irritation were observed in the control and the treatment group 24 and 48 hours after removal of the occlusive bandage. Based on the results of the study, the substance showed no evidence for sensitizing properties.

Respiratory sensitisation

Endpoint conclusion
Endpoint conclusion:
no study available

Justification for classification or non-classification

According to the CLP Regulation (EC 1272/2008), 3.4 Respiratory or skin sensitisation section, skin sensitizer means a substance that will lead to an allergic response following skin contact.

Based on the Buehler assay results, a substance is considered a skin sensitiser when more than 15 % of the tested population gives a positive response to a topical induction dose.

No signs of irritation were observed in the control and the treatment groups 24 and 48 hours after removal of the occlusive bandage.

In conclusion, Acid Red 057 does not meet the criteria to be classified as skin sensitizer.