Ethyl 2-methyl-4-oxo-6-pentylcyclohex-2-ene-1-carboxylate

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

8 November 1984 to 7 January 1985

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1984

Report date:

1985

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: Colworth photoallergy (FCA and topical application)

GLP compliance:

no

Type of study:

other: Freund's complete adjuvant test and topical application

Justification for non-LLNA method:

The Guinea pig photoallergy test with Calyxol was already available (performed in 1985) and reliable to evaluate the skin sensitization potential and the classification determination.

Test material

Test material information

Constituent 1

Reference substance name:

rel-(1R,6S)-ethyl 2-methyl-4-oxo-6-pentylcyclohex-2-enecarboxylate

Molecular formula:

C15H24O3

IUPAC Name:

rel-(1R,6S)-ethyl 2-methyl-4-oxo-6-pentylcyclohex-2-enecarboxylate

Constituent 2

Reference substance name:

rel-(1R,6R)-ethyl 2-methyl-4-oxo-6-pentylcyclohex-2-enecarboxylate

Molecular formula:

C15H24O3

IUPAC Name:

rel-(1R,6R)-ethyl 2-methyl-4-oxo-6-pentylcyclohex-2-enecarboxylate

In vivo test system

Test animals

Species:

guinea pig

Strain:

Hartley

Remarks:

Albino

Sex:

male/female

Details on test animals and environmental conditions:

Animals are housed wither singly or in pairs of the same sex, in suspended cages with wire-mesh floors. They have tree access to pelleted commercial guinea pig diet and water, and they receive a handful of hay each working day and few cabbage pieces 3 or 5 times a week. All animals were weight weekly. Two groups of 12 guinea pigs weighing 350-450 gare used for the induction and challenge tests.

Study design: in vivo (non-LLNA)

Induction

Route:

epicutaneous, open

Vehicle:

other: DEA

Concentration / amount:

10% Calyxol in DEA

Day(s)/duration:

25 min application (repeated 24 hours later)

Adequacy of induction:

other: maximum non-photoirritant or slightly photoirritant concentration to a maximum of 10% concentration of the test substance

Challenge

Challenge 1

No.:

#1

Route:

epicutaneous, open

Vehicle:

other: DEA

Concentration / amount:

10%; 1% and 0.1% of Calyxol in DEA

Day(s)/duration:

10 to 14 days after induction

Challenge 2

No.:

#2

Route:

epicutaneous, open

Vehicle:

other: DEA

Concentration / amount:

10%; 1%; 0.1% of Calyoxl in DEA

Day(s)/duration:

6 or 7 days later the 1st challenge

No. of animals per dose:

12 guinea pigs ( 2 or 3 concentrations of test substance applied to each during the challenge test)

Details on study design:

To induce photoallergy guinea pigs were injected with FCA and treated topically with test substance and irradiated with light. Treatment and irradiation were repeated 24h later. The guinea pigs were challenge 10-14 days later by topical application and irradiation. A second challenge was done 6 days later.

Challenge controls:

2 Groups of Guinea pigs are used for this test ( group A is treated with test substance when group B is the control group treated with solvent only during the induction phase)
Both group are treated with the test substance within the challenge test.

Results and discussion

In vivo (non-LLNA)

Results

Results 1

Key result

Reading:

1st reading

Hours after challenge:

72

Group:

test chemical

Dose level:

10%; 1% and 0.1%

No. with + reactions:

1

Total no. in group:

12

Clinical observations:

Contact sensitivity

Results 2

Key result

Reading:

2nd reading

Hours after challenge:

72

Group:

test chemical

Dose level:

10%; 1% and 0.1%

No. with + reactions:

2

Total no. in group:

12

Clinical observations:

photo-allergy

Any other information on results incl. tables

2 of 12 guinea pigs in test group A became photo allergic. One of the postive animal also reacted at the sensitivity test site at the second challenge; sensitivity the reaction being less intense than the photo allergic reaction.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The test substance Calyxol had a weak photoallergic potential in this test, neverthless only 1 animal developped a contact sensitivity. Therefore the Calyxol is not classified skin sensitizer according to the GHS criteria.

Executive summary:

Calyxol is tested in this test demonstrate the photoallergy potential of this susbtance.

To induce photoallergy guinea pigs were injected with FCA and treated topically with test substance and irradiated with light. Treatment and irradiation were repeated 24h later. The guinea pigs were challenge 10-14 days later by topical application and irradiation. A second challenge was done 6 days later.

2 of 12 guinea pigs in test group A became photo allergic. One of the postive animals also developed a contact sensitivity.

Therefore the Calyxol is not classified skin sensitizer according to the GHS criteria.