4,4'-ethylidenediphenyl dicyanate

Endpoint summary

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:

July 1989

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study, GLP-compliant

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to other study

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Deviations:

yes

Remarks:

; see comments

Principles of method if other than guideline:

The substance could not be prepared in an injectable form (the test laboratory confirmed that a range of solvents were tried). Therefore for the first induction the substance was applied dermally over the site where adjuvant had been injected. Both topical induction stages involved wetting of the skin with aqueous sodium lauryl sulphate followed by a 48 hour application of the test substance under an occlusive dressing

GLP compliance:

yes

Type of study:

guinea pig maximisation test

Species:

guinea pig

Strain:

Dunkin-Hartley

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: David Hall Limited, Darly Oaks, Newchurch, Burton-on-Trent, Staffordshire
- Age at study initiation: less than one year old
- Weight at study initiation: 370-447 g
- Housing: gang housing
- Diet: FDI Guinea Pig Diet, supplied by Special Diets Services (I Stepfield, Witham, Essex, CM8 3AD), supplemented with hay and allowed food
- Water (e.g. ad libitum): tap water
- Acclimatisation period: 7 days prior to test commencement

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19-21°C
- Humidity (%): 51%
- Photoperiod (hrs dark / hrs light): A 12 h light/dark cycle was in operation (light hours 0700-1900 h)

Route:

other: The substance could not be prepared in an injectable form (the test laboratory confirmed that a range of solvents were tried). Therefore for the first induction the substance was applied dermally over the site where adjuvant had been injected. Both topica

Vehicle:

paraffin oil

Concentration / amount:

Concentration of test material and vehicle used at induction:
- Topical: 25% v/v in paraffin oil

Concentration of test material and vehicle used for each challenge:
- 10% v/v in paraffin oil

Route:

epicutaneous, occlusive

Vehicle:

paraffin oil

Concentration / amount:

Concentration of test material and vehicle used at induction:
- Topical: 25% v/v in paraffin oil

Concentration of test material and vehicle used for each challenge:
- 10% v/v in paraffin oil

No. of animals per dose:

- Number of animals in test group: 20
- Number of animals in negative control group: 20

Details on study design:

The substance could not be prepared in an injectable form (the test laboratory confirmed that a range of solvents were tried). Therefore for the first induction the substance was applied dermally over the site where adjuvant had been injected. Both topical induction stages involved wetting of the skin with aqueous sodium lauryl sulphate followed by a 48 hour application of the test substance under an occlusive dressing.

Positive control substance(s):

yes

Remarks:

Positive control substance: 2,4-dinitro-chlorobenzene (DNCB)

Positive control results:

Checked at 6 monthly intervals. The most recent positive control test with DNCB was completed on 16 December 1988 when 100% of the test group animals reacted positively.

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

10%

No. with + reactions:

0

Total no. in group:

20

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 10%. No with. + reactions: 0.0. Total no. in groups: 20.0.

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

10%

No. with + reactions:

0

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: 0.0. Total no. in groups: 20.0.

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

10%

No. with + reactions:

0

Total no. in group:

20

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: negative control. Dose level: 10%. No with. + reactions: 0.0. Total no. in groups: 20.0.

Reading:

2nd reading

Hours after challenge:

48

Group:

negative control

Dose level:

10%

No. with + reactions:

0

Total no. in group:

20

Remarks on result:

other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: negative control. Dose level: 10%. No with. + reactions: 0.0. Total no. in groups: 20.0.

Dose Ranging Test for Induction:

Only slight reactions were noted at 2 sites treated topically with the test material at one concentration only, 25% v/v in paraffin oil. A concentration of 25% v/v in paraffin oil was selected for the topical application (phases 1 and 2) of induction in the test group.

Main Test - Induction:

Moderate irritation was noted in the test group after the first topical application, with slight reactions after the second application. The control groups reacted slightly after the first application only.

Dose Ranging Test for Challenge:

Slight reactions.were noted in both guinea pigs at a concentration of 25% v/v in paraffin oil. A concentration of 10% v/v in paraffin oil was selected for challenge.

Main Test - Challenge:

Following challenge with the test item at a concentration of 10% v/v, none of the 20 test group animals showed positive reactions to this application. None of the 20 control group animals, which had previously only been exposed to the vehicle, paraffin oil, showed a positive reaction to this application.

Body Weights:

Body weights were recorded at main test commencement and on test completion. Body weight gains were acceptable.

Clinical Signs:

No clinical signs, other than skin reactions induced by treatment, were noted.

Interpretation of results:

not sensitising

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The test item did not show a sensitization reaction in guinea pigs.

Executive summary:

The skin sensitization test was performed on guinea pigs according to EU-testing method B.6. The substance could not be prepared in an injectable form (the test laboratory confirmed that a range of solvents were tried). Therefore for the first induction the substance was applied dermally over the site where adjuvant had been injected. Both topical induction stages involved wetting of the skin with aqueous sodium lauryl sulphate followed by a 48 hour application of the test substance under an occlusive dressing. Satisfactory skin responses were noted at induction. The substance is not classified as a skin sensitiser.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

Migrated from Short description of key information:
The skin sensitization test was performed on guinea pigs according to EU-testing method B.6. The substance could not be prepared in an injectable form (the test laboratory confirmed that a range of solvents were tried). Therefore for the first induction the substance was applied dermally over the site where adjuvant had been injected. Both topical induction stages involved wetting of the skin with aqueous sodium lauryl sulphate followed by a 48 hour application of the test substance under an occlusive dressing. Satisfactory skin responses were noted at induction. The substance is not classified as a skin sensitiser.

Justification for selection of skin sensitisation endpoint:
Reliable data from ELINCS-notification (Klimisch 1)

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

Based on the data available the substance is not classified or labeled according to Directive 67/548/EEC (DSD) or Regulation 1272/2008/EC (CLP).