Benzyl formate

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Basic data given, acceptable, well documented publication, no guideline and no GLP study.

Data source

Reference

Reference Type:

publication

Title:

The Freund's Complete Adjuvant Test and the Open Epicutaneous Test - A Complementary Test Procedure for Realistic Assessment of Allergenic Potential

Author:

Klecak G.

Year:

1985

Bibliographic source:

Curr. Probl. Derm, Vol. 14, pp. 152-171

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

The open epicutaneous test represents an animal bioassay conducted with guinea pigs and designated to generate quantitative data. The generation of skin sensitisation data includes a 3 step way. In the pretesting phase the primary irritation threshold concentration of the test substance is determined. The induction phase consists of a 3-week period of daily open applications. The final determination whether sensitisation has occurred or not takes place in the final challenge phase.

GLP compliance:

no

Type of study:

open epicutaneous test

Justification for non-LLNA method:

Information from a well documented publication is available and used in a weight of evidence approach.

Test material

Test material information

Constituent 1

Reference substance name:

Benzyl formate

EC Number:

203-214-4

EC Name:

Benzyl formate

Cas Number:

104-57-4

Molecular formula:

C8H8O2

IUPAC Name:

benzyl formate

In vivo test system

Test animals

Species:

guinea pig

Strain:

not specified

Sex:

male/female

Details on test animals and environmental conditions:

TEST ANIMALS
- Weight at study initiation: 300-450 g

Study design: in vivo (non-LLNA)

Induction

Route:

epicutaneous, open

Vehicle:

not specified

Concentration / amount:

100 %, 30 %, 10 %, 3 %, 1 % and 0.3 % / 21 x 0.1 mL

Day(s)/duration:

Day 0 - 20 / 3 weeks (4 weeks)

Adequacy of induction:

not specified

Challenge

Route:

epicutaneous, open

Vehicle:

not specified

Concentration / amount:

0.025 mL

Day(s)/duration:

Days 21 - 35 / 24, 48, 72 hours

Adequacy of challenge:

other: minimal irritating concentration and some lower primary non irritating concentrations

No. of animals per dose:

Test group: At least 6 animals per dose
Control group: 10 animals per dose

Details on study design:

RANGE FINDING TESTS (Day 1):
Four guinea pigs were used for determination of the primary irritation concentration of the test substance so that non-irritating concentrations may be chosen for challenge.

MAIN STUDY
A. INDUCTION EXPOSURE (Day 0 - 20, epicutaneous)
- No. of exposures: 21 applications (daily for 3 weeks or 5 times weekly during 4 weeks)
- Exposure period: For 3 weeks (4 weeks)
- Control group: No treatment or 21 x 0.1 mL epicutaneous application of vehicle.
- Site: Clipped flank, on an area of 8 cm²
- Frequency of applications: Daily
- Readings: 24 hours after each application
- Duration: 3 weeks (4 weeks)
- Concentrations: if possible 100, 30, 10, 3, 1 and 0.3 %

B. CHALLENGE EXPOSURE (Days 21 - 35, epicutaneous)
- No. of exposures: 2
- Day(s) of challenge: 21 and 35
- Site: On the contralateral flank (2 cm²)
- Concentration: 0.025 mL of minimal irritating concentration and some lower primary non irritating concentrations
- Evaluation (hr after challenge): 24, 48 and 72 hours

Challenge controls:

no data

Positive control substance(s):

no

Results and discussion

Positive control results:

no data

In vivo (non-LLNA)

Results

Key result

Reading:

other: Number of readings is not specified in the study

Group:

test chemical

Dose level:

10 %

No. with + reactions:

0

Remarks on result:

no indication of skin sensitisation

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

In an open epicutaneous test (OET) groups of guinea pigs showed no sensitising effect at a concentration of 10 %.

Executive summary:

The skin sensitising potential of the test item was tested in a open epicutaneous test with guinea pigs. The test was conducted on groups of at least 6 male and female animals weighing 300 - 450 g. Daily applications were made for 3 weeks to a clipped 8 cm² area on the flank of each guinea pig. The test sites were not covered and the reactions were read 24 hours after each application. A total of 21 applications of 0.1 mL test material in an unspecified vehicle were made for 21 days. The 10 controls were either left untreated or treated with 0.1 mL test material in an unspecified vehicle for 21 days. At the challenge phase, both the test and control animals were treated at some lower primary non-irritating concentrations. At a test concentration of 10 % no sensitising effect were observed.