[(3aS*,4R*,5S*,7R*,7aS*)-4,7-methano-2,3,3a,4,5,6,7,7a-octahydro-1H-inden-5-yl]methyl acetate

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

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)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.6 (Skin Sensitisation)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

The test was conducted according to the recognised OECD guideline for the testing of chemicals (OECD406, May 12, 1981) with particular reference to the publications by Magnusson B and Kligman AM: The identification of contact allergens by animal assay. The guinea pig maximisation test (J.Invest.Dermatol.,52,268-276,1969) and Allergic contact dermititis in the guinea pig (Thomas Publishers, Springfield, Illinois, 1970).

Test material

Test material information

Constituent 1

Reference substance name:

[(3aS*,4R*,5S*,7R*,7aS*)-4,7-methano-2,3,3a,4,5,6,7,7a-octahydro-1H-inden-5-yl]methyl acetate

Molecular formula:

C13H20O2

IUPAC Name:

[(3aS*,4R*,5S*,7R*,7aS*)-4,7-methano-2,3,3a,4,5,6,7,7a-octahydro-1H-inden-5-yl]methyl acetate

In vivo test system

Test animals

Species:

guinea pig

Strain:

Pirbright-Hartley

Sex:

male/female

Details on test animals and environmental conditions:

TEST ANIMALS
- Species and Substrain: Pirbright white Bor: DHPW (SPF)
- Source: Firma Winkelmann, Versuchstierzucht, Gartenstr. 27
- Weight at study initiation: male 314-423 g; female 302-364 g
- Housing: Collective housing up to a maximum of 5 animals per cage (Macrolon type IV)
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: 5-days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22±3°C
- Humidity (%): 30-70%
- Photoperiod (hrs dark / hrs light): 12 house light: 12 hours dark
- Illumination: 120 lux artificial lighting from 7.00am - 7.00pm

Study design: in vivo (non-LLNA)

Induction

Route:

intradermal

Vehicle:

peanut oil

Concentration / amount:

According to the information from the study sponser and the test requirements. The concentrations used are based on the original concentration of the test article as provided by the sponsor, i.e. 50% in white vaseline.

TEST GROUP
- 0.1 ml FCA 50% (w/w) dilutred in water
- 0.1 ml test article diluted in peanut butter oil (final concentration: 5%)
- 0.1 ml test article emulsified in FCA/water (final concentration: 5%)

CONTROL GROUP
- 0.1 ml FCA 50% (w/w) diluted in water
- 0.1 ml vehicle (undiluted)
- 0.1 ml vehicle 50% (w/w) emulsified with FCA

Adequacy of induction:

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

Challenge

No.:

#20

Route:

epicutaneous, occlusive

Vehicle:

peanut oil

Concentration / amount:

According to the information from the study sponser and the test requirements. The concentrations used are based on the original concentration of the test article as provided by the sponsor, i.e. 50% in white vaseline.

TEST GROUP
- 0.1 ml FCA 50% (w/w) dilutred in water
- 0.1 ml test article diluted in peanut butter oil (final concentration: 5%)
- 0.1 ml test article emulsified in FCA/water (final concentration: 5%)

CONTROL GROUP
- 0.1 ml FCA 50% (w/w) diluted in water
- 0.1 ml vehicle (undiluted)
- 0.1 ml vehicle 50% (w/w) emulsified with FCA

Day(s)/duration:

2 days

Adequacy of challenge:

highest non-irritant concentration

No. of animals per dose:

10 males and 10 females treated at 100% as the test article was found to be non-irritating at the highes concentration in the induction phase.

Details on study design:

RANGE FINDING TESTS:
- Intradermal injection: Final concentration of 5%. Since this concentration produced neither severe systemic toxicity, nor local necrosis or ulceration, it was used accordingly. Two animals were employed for the concentration tested, skin reactions were recorded 48-hours following treatment.

- Dermal Application: the test article was undiluted. A closed patch exposure was effected by means of an occlusive bandage. Two animals were employed for each concentration tested and skin reactions were recoreded 48-hour post application. Since this concentration was non-irritating, it was used accordingly.

MAIN STUDY
A. INDUCTION EXPOSURE (Day 0)
- No. of exposures: Three intradermal injections
- Test groups: 0.1 ml 5% test substance
- Control group: vehicle controls (FCA 50% (w/w) in water, 100% peanut oil, 50% peanut oil (w/w) emulsified with FCA)
- Site: Injections were on the dorsum either side of the spine

B. CAUSING OF A LOCAL IRRITATION (Day 7)
Seven days after the dermal application was initiated. The fur of all guinea pigs was clipped in the dorsal test area and applied with a 10% sodium lauryl sulphate mixture in Vaseline for 24-hours to create a local dermal irritation. The test article was spread in a thick layer [to saturation] over a 4 x 5 cm patch of filter paper, which was secured with occlusive dressing for 48 hours. Control animals received a patch loaded with vehicle alone.

C. CHALLENGE PROCEDURE (Day 21)
- No. of exposures: Single exposure to the maximal non-irritating concentration in occlusive dressing
- Day(s) of challenge: 21-day (14 days after the induction of local irritation)
- Exposure period: 24-hours
- Site: Right flank
- Concentrations: 100% test substance
- Evaluation (hr after challenge): 24 and 48 hours after removal of challenge exposure

Positive control substance(s):

yes

Remarks:

2,4-Dinitrochlorobenzene and Benzocaine

Results and discussion

Positive control results:

The reaction to the positive control substances 2,4-dinitrochlorobenzene (strong sensitiser) and benzocaine (moderate sensitiser) is tested periodically. The last test with an acceptable level of response to each of these substances was performed in October 1991.

In vivo (non-LLNA)

Results

Results 1

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

100% test article concentration

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: 100% test article concentration. No with. + reactions: 0.0. Total no. in groups: 20.0.

Results 2

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

100% test article concentration

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: 100% test article concentration . No with. + reactions: 0.0. Total no. in groups: 20.0.

Any other information on results incl. tables

Sensitisation rate (%) at 24 hours: 0.0

Sensitisation rate (%) at 48 hours: 0.0

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

According to the OECD guideline for testing of chemicals (OECD 406, May 12, 1981), since no animal showed an allergic response, the test article, TCD-M-acetate may be classified as a non-sensitiser.

Executive summary:

The potential skin sensitising properties of TCD-M-acetate were assessed in a GLP compliant OECD 406 guinea pig maximisation test using 20 test and 20 control animals. Following intradermal induction exposure to the test article or vehicle, the animals were subjected a dermal challenge exposure with the test article 14-days later. Allergic responses to the challenge procedure were evaluated 24 and 48 hours post exposure. No animal demonstrated any allergic response to the test article.