1,8-bis(phenylthio)anthraquinone

Endpoint summary

Description of key information

Solvent Yellow 163 is a skin sensitiser.

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

16-10-1997 to 22-12-1998

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Deviations:

no

GLP compliance:

yes

Type of study:

Buehler test

Justification for non-LLNA method:

Data from a reliable in vivo test conducted before the enforcement of Commission Regulation (EU) 640/2012 of 06 July 2012 amending, for the purpose of its adaptation to technical progress, Regulation (EC) No 440/2008 laying down test methods pursuant to Regulation (EC) No 1907/2006 of the European Parliament and of the Council on the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) are available.

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: Pa 243/244-22 bei 700C getr.

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Room temperature

Species:

guinea pig

Strain:

Dunkin-Hartley

Remarks:

Pirbright White

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Charles River GmbH - Wiga, Kisslegg, FRG
- Females (if applicable) nulliparous and non-pregnant: yes
- Microbiological status of animals, when known:
- Age at study initiation: Young adult animals
- Weight at study initiation: 318 - 400 g
- Housing: Makrolon, type IV (5 animals per cage)
- Diet: Kliba Labordiät (Kaninchen- Meerschweinchen-Haltungsdiät) ad libitum
- Water: ad libitum
- Acclimation period: 8 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21 - 25
- Humidity (%): 30-70
- Photoperiod (hrs dark / hrs light): 12 h light (6.00 a.m. - 6.00 p.m.) 12 h darkness (6.00 p.m. - 6.00 a.m.)

Route:

epicutaneous, occlusive

Vehicle:

CMC (carboxymethyl cellulose)

Remarks:

1% Tylose CB 30.000

Concentration / amount:

10 %

Day(s)/duration:

0

Adequacy of induction:

highest concentration used causing mild-to-moderate skin irritation and well-tolerated systemically

Route:

epicutaneous, occlusive

Vehicle:

CMC (carboxymethyl cellulose)

Remarks:

1% Tylose CB 30.000

Concentration / amount:

10 %

Day(s)/duration:

7 d

Adequacy of induction:

highest concentration used causing mild-to-moderate skin irritation and well-tolerated systemically

Route:

epicutaneous, occlusive

Vehicle:

CMC (carboxymethyl cellulose)

Remarks:

1% Tylose CB 30.000

Concentration / amount:

10 %

Day(s)/duration:

14 d

Adequacy of induction:

highest concentration used causing mild-to-moderate skin irritation and well-tolerated systemically

No.:

#1

Route:

epicutaneous, occlusive

Vehicle:

CMC (carboxymethyl cellulose)

Remarks:

1 % Tylose CB 30.000

Concentration / amount:

5 %

Day(s)/duration:

24

Adequacy of challenge:

highest non-irritant concentration

No.:

#2

Route:

epicutaneous, occlusive

Vehicle:

CMC (carboxymethyl cellulose)

Remarks:

1 % Tylose GB 30.000

Concentration / amount:

5 %

Day(s)/duration:

48 h

Adequacy of challenge:

highest non-irritant concentration

No. of animals per dose:

The study was performed on 20 guinea pigs in the test group and 10 animals in each of control groups 1 and 2.

Details on study design:

3 inductions were conducted.
Application frequency: one application per week; days 0, 7 and 14 on the same application area 2 x 2 cm gauze patches (6 Iayers surgical gauze Ph. Eur. from Lohmann GmbH & Co.KG) containing the test substance formulation were applied to the skin of the flank under an occlusive dressing. The dressing consisted of rubberized linen patches (4 x 4 cm from Russka), patches of Idealbinde (5 x 5 cm from Pfälzische Verbandstoff-Fabrik) and Fixomull© Stretch (adhesive fleece) from Beiersdorf AG. 0.5 ml of the test substance formulation was applied to each animal.
The control groups were treated analogously to the test group but only with the vehicle without the test substance. A challenge was carried out 14 days after the third induction. A rechallenge was performed one week after the challenge. 2 x 2 cm gauze patches (6 Iayers surgical gauze Ph. Eur. from Lohmann GmbH & Co.KG) containing the test substance formulation were applied to the skin of the flank under an occlusive dressing. The dressing consisted of rubberized linen patches (4 x 4 cm from Russka), patches of Idealbinde (5 x 5 cm from Pfälzische Verbandstoff-Fabrik) and Fixomull Stretch (adhesive fleece) from Beiersdorf AG. 0.5 ml of the test substance formulation was applied to each animal.

Challenge controls:

The test group and control group 1 were treated with the test substance formulation. Additionally 1 % Tylose OB 30.000 in aqua bidest. was applied as a vehicle control. Control group 2 only received 1 % Tylose GB 30.000 in aqua bidest.

Positive control substance(s):

no

Remarks:

but data was available from separate test.

Positive control results:

A positive control (reliability check) with a known sensitizer is not included in this study. However, a separate study is performed twice a year in the Iaboratory. The positive control with Alpha-Hexylcinnamaldehyde techn. 85 % showed that the chosen guinea pig strain was able to detect sensitizing compounds under the Iaboratory conditions chosen.

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

induction: vehicle only, challenge: 5 %

No. with + reactions:

0

Total no. in group:

9

Clinical observations:

1 animal died

Reading:

2nd reading

Hours after challenge:

48

Group:

negative control

Dose level:

induction: vehicle only, challenge: 5 %

No. with + reactions:

0

Total no. in group:

9

Clinical observations:

1 animal died

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

induction: 10 % and challenge: 5 %

No. with + reactions:

10

Total no. in group:

20

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

induction: 10 % and challenge: 5 %

No. with + reactions:

9

Total no. in group:

20

Reading:

rechallenge

Hours after challenge:

24

Group:

negative control

Dose level:

induction: vehicle only, challenge: 5 % & rechallenge: 5 %

No. with + reactions:

0

Total no. in group:

20

Reading:

rechallenge

Hours after challenge:

48

Group:

negative control

Dose level:

induction: vehicle only, challenge: 5 % & rechallenge: 5 %

No. with + reactions:

0

Total no. in group:

20

Reading:

rechallenge

Hours after challenge:

24

Group:

test chemical

Dose level:

induction: 10 %, challenge: 5 % & rechallenge: 5 %

No. with + reactions:

5

Total no. in group:

20

Reading:

rechallenge

Hours after challenge:

48

Group:

test chemical

Dose level:

induction: 10 %, challenge: 5 % & rechallenge: 5 %

No. with + reactions:

6

Total no. in group:

20

Reading:

1st reading

Hours after challenge:

24

Group:

positive control

Dose level:

induction: 25 %, challenge: 10 %

No. with + reactions:

11

Total no. in group:

19

Reading:

2nd reading

Hours after challenge:

48

Group:

positive control

Dose level:

induction: 25 %, challenge: 10 %

No. with + reactions:

11

Total no. in group:

19

Reading:

rechallenge

Hours after challenge:

24

Group:

positive control

Dose level:

induction: 25 %, challenge: 10 % & rechallenge: 10 %

No. with + reactions:

16

Total no. in group:

19

Reading:

rechallenge

Hours after challenge:

48

Group:

positive control

Dose level:

induction: 25 %, challenge: 10 % & rechallenge: 10 %

No. with + reactions:

15

Total no. in group:

19

The evaluation of the results is based on the criteria of the Commission Directive 961541EC of JuIy 30, 1996 for the 22th Amendment of the Directive 67/548 EEC (Publication No. L 248, p. 228 - 229, 1996). The number of animals with skin findings at 24 and/or 48 hours after the removal of the patch is taken into account for the determination of the sensitization rate. The evaluation sensitizing results if at least 15 per cent of the test animals exhibit skin reactions.

Induction:

All inductions were performed with 10 % test substance preparations. The first induction caused discrete or patchy erythema in 5 out of 20 test group animals. After the second induction discrete or patchy erythema was observed in 2 out of 20 test group animals. 1 test group animal showed moderate and confluent erythema. The third induction caused discrete or patchy erythema in 4 out of 20 test group animals. Moderate and confluent erythema was seen in 4 test group animals. 1 % Tylose CB 30.000, which was applied as a vehicle control to all animals did not cause any skin reactions. The test substance preparation caused a slight yellow discoloration of the skin. It was possible to evaluate the skin reactions.

Challenge:

The challenge with a 5 % test substance preparation caused the following skin reactions:

Readings at 24 hours after removal of the patches

- no visible change in all animals of control group 1

- discrete or patchy erythema in 4 out of 20 test group animals

- moderate and confluent erythema in 3 out of 20 test group animals

- moderate and confluent erythema with swelling in 3 out of 20 test group animals

Readings at 48 hours after removal of the patches

- no visible change in all animals of control group 1

- discrete or patchy erythema in 7 out of 20 test group animals

- moderate and confluent erythema in 2 out of 20 test group animals

1 % Tylose CB 30,000, which was applied as a vehicle control to all animals, did not cause any skin reactions. The test substance preparation caused a slight yellow discoloration of the skin. lt was possible to evaluate the skin reactions.

Rechallenge:

The rechallenge with a 5 % test substance preparation caused the following skin reactions:

Readings at 24 hours after removal of the patches

- no visible changes in all animals of control groups 1 and 2

- discrete or patchy erythema in 1 out of 20 test group animals

- moderate and confluent erythema with swelling in 4 out of 20 test group animals

Readings at 48 hours after removal of the patches

- no visible changes in all animals of control groups 1 and 2

- discrete or patchy erythema in 4 out of 20 test group animals

- moderate and confluent erythema in 1 out of 20 test group animals

- moderate and confluent erythema with swelling in 1 out of 20 test group animals

1 % Tylose GB 30.000, which was applied as a vehicle control to all animals, did not cause any skin reactions.

The test substance preparation caused a slight yellow discoloration of the skin. It was possible to evaluate the skin reactions.

Interpretation of results:

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

Conclusions:

The results of this study show that test substance has a sensitizing effect on the skin of the guinea pig in the Buehler Test under the test conditions chosen.

Executive summary:

The substance was tested for its sensitizing effect on the skin of the guinea pig in the Buehler test based on the method of Buehler, E.V. (1965). All inductions were performed with 10 % test substance preparations. After the first induction discrete or patchy erythema was observed in test group animals. The second and third induction caused discrete or patchy erythema and moderate and confluent erythema in test group animals. Two challenges were performed 14 and 21 days after the last induction. After the challenges with a 5 % test substance preparation discrete or patchy erythema and moderate and confluent erythema, in some cases with swelling were noted in test. The number of animals with skin findings at 24 and 48 hours after challenge were 10/20 and 9/20, respectively, while 24 and 48 hours after rechallenge were 5/20 and 6/20, respectively. Based on these findings, it was concluded that the substance has a sensitizing effect on the skin of the guinea pig in the Buehler test under the test conditions chosen.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (sensitising)

Additional information:

Solvent Yellow 163 was tested for its sensitizing effect on the skin of the guinea pigs in the Buehler test based on the method of Buehler, E.V. (1965). All inductions were performed with 10 % test substance preparations. After the first induction discrete or patchy erythema was observed in test group animals. The second and third induction caused discrete or patchy erythema and moderate and confluent erythema in test group animals.

Two challenges were performed 14 and 21 days after the last induction. After the challenges with a 5 % test substance preparation discrete or patchy erythema and moderate and confluent erythema, in some cases with swelling were noted in test.

The number of animals with skin findings at 24 and 48 hours after challenge were 10/20 and 9/20, respectively, while 24 and 48 hours after rechallenge were 5/20 and 6/20, respectively. Based on these findings, it was concluded that the substance has a sensitizing effect on the skin of the guinea pig in the Buehler test under the test conditions chosen.

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

In the available Buehler test, 10/20 and 9/20 animals had skin reactions after 24 and 48 hours following challenge. The concentration for topical induction was 10 %. Hence, Solvent Yellow 163 should be classified as Skin Sensitiser 1B according to EU CLP.