Octocrilene

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2000-11-13 to 2000-12-07

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2001

Report date:

2001

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Version / remarks:

adopted July 17, 1992

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.6 (Skin Sensitisation)

Version / remarks:

July 30, 1996

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2600 (Skin Sensitisation)

Version / remarks:

August 2000

Deviations:

no

Test guideline 4

Qualifier:

according to guideline

Guideline:

other: Japan MAFF guideline, 59 Noh San No. 4200, January 28, 1985.

Deviations:

no

GLP compliance:

yes

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

Study was performed before LLNA was formally validated and available as OECD guideline in 2002.

Test material

Test material information

Constituent 1

Reference substance name:

Octocrilene

EC Number:

228-250-8

EC Name:

Octocrilene

Cas Number:

6197-30-4

Molecular formula:

C24H27NO2

IUPAC Name:

2-ethylhexyl 2-cyano-3,3-diphenylacrylate

Details on test material:

- Name of test material (as cited in study report): Uvinul N 539 T
- Physical state: Liquid, slight yellowish
- Analytical purity: 99.4 area% (GC)
- Lot/batch No.: 133635; date of production: April, 2000
- Stability under test conditions: confirmed
- Storage condition of test material: room temperature

In vivo test system

Test animals

Species:

guinea pig

Strain:

Dunkin-Hartley

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
female guinea pigs, Hsd Poc:DH (SPF)
- Source: Harlan Winkelmann GmbH , Borchen, FRG
- Age at study initiation: ca. 7 weeks
- Weight at study initiation: 351 - 432 g
- Housing: 5 per cage, Stainless steel wire mesh cages with plastic-coated grating, minimum floor area : 2000 cm²
- Diet (ad libitum): Labordiät (Kaninchen-Meerschweinchen-Haltungsdiät, Provimi Kliba SA, Kaiseraugst, Switzerland
- Water (ad libitum): tap water
- Acclimation period: 6 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21-25°C
- Humidity (%): 30-70%
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): 12/12

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

intradermal

Vehicle:

other: Paraffin oil or Freund's adjuvant / 0.9% aqueous NaCI-solution (1 :1 )

Concentration / amount:

5%

Day(s)/duration:

not applicable

Induction 2

Route:

epicutaneous, occlusive

Vehicle:

unchanged (no vehicle)

Concentration / amount:

100%

Day(s)/duration:

48 hours

Challenge

No.:

#1

Route:

epicutaneous, occlusive

Vehicle:

unchanged (no vehicle)

Concentration / amount:

100%

Day(s)/duration:

24 hours

Adequacy of challenge:

highest non-irritant concentration

No. of animals per dose:

10 (test group)
5 (control group)

Details on study design:

RANGE FINDING TESTS:
A pretest was carried out with 2 females guinea pigs for intradermal induction (5% in Freund' Adjuvant/0.9% saline and 5% in paraffin oil) and with 4 female guinea pigs for epicutaneous application (75% in Lutrol E 400 and undiluted). In the epicuataneous Pretest, animals pretreated with Freund's adjuvant / 0 .9% aqueous NaCI-solution (1 : 1) each, in the same manner as intradermal pretest without test substance about 3 weeks prior to the application of the test substance were used for detecting a possible influence on irritating effects of previous intradermal treatment with Freund's adjuvant. The test substance was applied to the skin of the flanks for 24 hours under occlusive dressing.


Based on the results of these findings, the concentrations for the main test were selected.

MAIN STUDY
A. INDUCTION EXPOSURE
1. Intradermal induction
- Test groups:
6 intradermal injections in groups of two per animal were applied to each animal.
a) front row. 2 injections each of 0. 1 ml Freund's adjuvant without test substance emulsified with 0. 9% aqueous NaCI-solution in a ratio of 1 : 1
b) middle row. 2 injections each of 0. 1 ml of a test substance formulation, 5% in paraffin oil
c) back row. 2 injections each of 0.1 m l Freund's adjuvant / 0.9% aqueous NaCI-solution (1 : 1) with test substance at 5%.
- Control group:
same treatment as test groups, but without the test substance added
- Site: shoulder
- Frequency of applications: single dose
- Concentrations: 5%
- reading: 24 h after beginning of application

2. Epicutaneous induction, one week after intradermal induction
- Test groups: application of the undiluted test substance (0.5 ml) using an occlusive patch
- Control group: untreated
- Site: shoulder, same area as in the case of the previous intradermal application
- Frequency of applications: single application
- Duration: 48 hours
- Concentrations: undiluted
- reading: 48 h after beginning of application

B. CHALLENGE EXPOSURE 14 days after epicutaneous induction
- No. of exposures: 1
- Day(s) of challenge: 1
- Exposure period: 1
- Test groups: application of the undiluted test substance (0.5 ml) using an occlusive patch
- Control group: as test group
- Site: flank, previously untreated
- Concentrations: undiluted
- Evaluation (hr after challenge): 24, 48

Positive control substance(s):

yes

Remarks:

Alpha-Hexylcinnamaldehyde; assessed in a separate study performed twice a year in the laboratory

Results and discussion

Positive control results:

Concentrations used:
Intradermal induction: 5% in Paraffin oil or Freund's adjuvant/0.9% aqueous NaCI-solution (1 :1)
Induction (epicutaneous) : 10 % in Lutrol E 400
1st+2nd challenge (epicutaneous): 5 % in Lutrol E 400

Results:
Test group: 10/10 animals with skin findings after 1st/2nd challenge with positive control substance
No skin findings after application of vehicle or in respective control groups.

Conclusion:
Based on these results, it was confirmed, that the positive control Alpha-Hexylcinnamaldehyde has a sensitizing effect on the skin of guinea pig strain used in the Maximization Test under the test conditions chosen.

In vivo (non-LLNA)

Results

Results 1

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

undiluted

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

none

Results 2

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

undiluted

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

none

Results 3

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

undiluted

No. with + reactions:

0

Total no. in group:

5

Clinical observations:

none

Results 4

Reading:

2nd reading

Hours after challenge:

48

Group:

negative control

Dose level:

undiluted

No. with + reactions:

0

Total no. in group:

5

Clinical observations:

none

Any other information on results incl. tables

Pretest

Intense erythema and swelling was observed in the 2 animals after intradermal application of the test substance in paraffin oil and Freund´s Adjuvans.

No skin reactions were observed in the 4 animals 1h, 24h or 48h after patch removal using 75% and 100% test substance.

Main test

Intradermal induction : Intense erythema and swelling in all test group animals.

Epicutaneous induction: Incrustation, partially open (caused by the intradermal induction) could be observed in addition to moderate and confluent erythema and swelling in all test group animals.

Challenge: No skin reactions were observed neither in the control nor in the test group animals.

BODY WEIGHTS

The expected body weight gain was generally observed in the course of the study.