3-cyano-3,5,5-trimethylcyclohexanone

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1990-10-30 to 1990-11-23

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1991

Report date:

1991

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.6 (Skin Sensitisation)

GLP compliance:

yes

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

A skin sensitization test according to OECD 406 has already excisted since 2000 and is sufficient for evaluation of the skin sensitisation potential of the test substance.

Test material

Test material information

Constituent 1

Reference substance name:

3-cyano-3,5,5-trimethylcyclohexanone

EC Number:

411-490-4

EC Name:

3-cyano-3,5,5-trimethylcyclohexanone

Cas Number:

7027-11-4

Molecular formula:

C10H15NO

IUPAC Name:

3-cyano-3,5,5-trimethylcyclohexanone

Details on test material:

Isophorone nitrile of Degussa AG. Batch No. 64 II / 192 V / 89. Purity 99.8 % (GC).

In vivo test system

Test animals

Species:

guinea pig

Strain:

Pirbright-Hartley

Sex:

male/female

Details on test animals and environmental conditions:

TEST ANIMALS: 
- Strain: Dunkin-Hartley, Pirbright White (Bor: DHPW)
- Sex: male/female - Source: Winkelmann Versuchstierzuchten, Borchen (Germany)
- Age at study initiation: 10 weeks
- Weight at study initiation: males 489-565 g, females 453-535 g
- Number of animals: 5 males + 5 females
- Housing: single housing
- Diet: ad libitum, special diet for guinea pigs, SSniff G
- Water: ad libitum, tab water
- Acclimation period: 6 days
ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 - 22 °C
- Humidity (%): 40 - 65 % (for short periods down to 30 %)
- Photoperiod (hrs dark / hrs light): 12 hours artificial light, 12 hours dark

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

intradermal and epicutaneous

Vehicle:

other: physiol. saline (intracutaneous) , paraffin oil (epicutaneous)

Induction 2

Concentration / amount:

1st application: Induction 0.05 % intracutaneous
2nd application: Induction 30 % occlusive epicutaneous
3rd application: Challenge 10 % occlusive epicutaneous

Challenge

Challenge 1

Route:

epicutaneous, occlusive

Vehicle:

other: physiol. saline (intracutaneous) , paraffin oil (epicutaneous)

Challenge 2

Concentration / amount:

1st application: Induction 0.05 % intracutaneous
2nd application: Induction 30 % occlusive epicutaneous
3rd application: Challenge 10 % occlusive epicutaneous

No. of animals per dose:

10 test
5 control

Details on study design:

- Controls: 5 males used for challenge + 5 females for rechallenge (not  used)
ADMINISTRATION/EXPOSURE 
- Preparation of test substance for induction: Dissolved in physiologic  saline or suspended in paraffin oil
- Induction schedule:    
Day 1: Injection (1st induction)   
Day 7: Application of 10 % sodium dodecyl sulfate   
Days 8-10: Patch treatment (2nd induction) of scapular area with test  substance 30 % in paraffin oil (1 ml, 48 hours; control: paraffin oil)
- Injection details: 0.1 ml each at 6 positions in scapular area:   
2 x Freund's Complete Adjuvant (FCA) / 0.9 % aqueous sodium chloride (=  vehicle) (1:1)   
2 x test substance 0.05 % in vehicle   
2 x test substance 0.05 % in vehicle / FCA (1:1)   
controls: vehicle instead of test substance
- Challenge schedule:    
Days 22-23: Patch treatment (0.2 ml, 24 hours) with test substance 10 %  in paraffin oil (left flank) and paraffin oil alone (right flank);  
control: identical treatment   
Days 24-25: Readings 24 and 48 hours after patch removal
- Rechallenge: not performed
- Positive control: p-phenylenediamine, performed Sept./Oct. 1989
EXAMINATIONS
- Grading system: Draize scores
- Pilot study: maximum non-irritating concentration (intradermal) and  slightly to moderately irritating plus non-irritating concentrations (epidermal)

Challenge controls:

treated with vehicle (Paraffin oil)

Positive control substance(s):

yes

Remarks:

p-phenylenediamine, performed Sep./Oct. 1989

Results and discussion

In vivo (non-LLNA)

Results

Results 1

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

10% preparation of test item in paraffin oil

No. with + reactions:

0

Total no. in group:

5

Clinical observations:

see below

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: negative control. Dose level: 10% preparation of test item in paraffin oil. No with. + reactions: 0.0. Total no. in groups: 5.0. Clinical observations: see below.

Results 2

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

10% preparation of test item in paraffin oil

No. with + reactions:

3

Total no. in group:

10

Clinical observations:

see below

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 10% preparation of test item in paraffin oil. No with. + reactions: 3.0. Total no. in groups: 10.0. Clinical observations: see below.

Results 3

Reading:

2nd reading

Hours after challenge:

48

Group:

negative control

Dose level:

10% preparation of test item in paraffin oil

No. with + reactions:

0

Total no. in group:

5

Clinical observations:

see below

Remarks on result:

other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: negative control. Dose level: 10% preparation of test item in paraffin oil. No with. + reactions: 0.0. Total no. in groups: 5.0. Clinical observations: see below.

Results 4

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

10% preparation of test item in paraffin oil

No. with + reactions:

5

Total no. in group:

10

Clinical observations:

see below

Remarks on result:

other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 10% preparation of test item in paraffin oil. No with. + reactions: 5.0. Total no. in groups: 10.0. Clinical observations: see below.

Any other information on results incl. tables

RESULTS OF PILOT STUDY: The test substance was non-irritant to the skin.
RESULTS OF TEST
- Sensitization reaction:
  erythema (all very slight, no edema) in 3/10 animals 24 hours and in  5/10 animals 48 hours after challenge patch removal
  no animals positive in control group
  no skin reaction upon vehicle treatment on opposite side (both groups)
- Clinical signs: Systemic effects could not be detected. The general  condition and body weight development of the test animals 

were not affected.

Applicant's summary and conclusion

Interpretation of results:

sensitising

Remarks:

Migrated information

Conclusions:

The test item Isophorone nitrile has sensitizing properties on the skin under conditions of this study.

Executive summary:

Isophorone nitrile was applied to the skin of guinea pigs to determine its sensitizing properties by the maximization test method. The test substance was dissolved in physiologic saline or suspended in paraffin oil. Following epidermal challange 5/10 treated animals produced erythemas at the exposed skin areas. None of the control animals produced any visible reaction. Therefore isophorone nitrile has sensitizing properties on the skin of guinea pig.