Registration Dossier

Administrative data

Endpoint:
skin sensitisation: in vivo (non-LLNA)
Type of information:
experimental study
Adequacy of study:
key study
Study period:
06 January 2003 - 07 February 2003
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: The study was conducted according to OECD guideline and in compliance with GLP.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2003
Report Date:
2003

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 406 (Skin Sensitisation)
GLP compliance:
yes
Type of study:
Buehler test

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
other: liquid

In vivo test system

Test animals

Species:
guinea pig
Strain:
Hartley
Sex:
male
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Elm Hill Breeding Labs, Chelmsford, MA
- Age at study initiation:Young adults
- Weight at study initiation: 463-605 grams
- Housing: group housing in suspended stainless steel caging with mesh floors
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: 26 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18-23
- Humidity (%): 41-62
- Air changes (per hr): n/a
- Photoperiod (hrs dark / hrs light): 12/12

Study design: in vivo (non-LLNA)

Inductionopen allclose all
Route:
epicutaneous, occlusive
Vehicle:
unchanged (no vehicle)
Concentration / amount:
positive control: 75% HCA in mineral oil
Induction and challenge: 100% test material
Challengeopen allclose all
Route:
epicutaneous, occlusive
Vehicle:
unchanged (no vehicle)
Concentration / amount:
positive control: 75% HCA in mineral oil
Induction and challenge: 100% test material
No. of animals per dose:
20 test
10 positive control
10 negative control
Details on study design:
A preliminary test to determine irritancy was carried out, applying the substance neat (100%) and diluted with acetone to yield concentrations of 75%, 50% and 25% w/w. Each concentration was applied to a test site using an occlusive 25mm Hilltop Chamber. The chambers were removed after 6 hours, and the test sites cleaned of residual test substance. The substance was applied undiluted in the main study.

The undiluted substance was applied topically, on the skin of 20 healthy guinea pigs, three times a week, for a three week induction period. Nine days after the first induction dose, a challenge dose of the test substance at its highest non-irritating concentration (100%) was applied to a naive site on each guinea pig. Approximately 24 and 48 hours after induction and challenge dose, the animals were scored for erythema. A similar induction and challenge application regimen with HCA in mineral oil was followed using an additional ten guinea pigs that served as concurrent positive controls for the study. Two naive control groups were maintained under identical environmental conditions and treated with the test or the positive control substance at challenge only.
Positive control substance(s):
yes
Remarks:
HCA

Results and discussion

Positive control results:
3/10 positive control animals showed reaction.

In vivo (non-LLNA)

Resultsopen allclose all
Reading:
1st reading
Hours after challenge:
24
Group:
test group
Dose level:
100%
No. with + reactions:
0
Total no. in group:
20
Clinical observations:
very faint to moderate erythema was noted at all test sites during the induction phase. Desquamation was noted at a few test sites following the seventh through ninth inductions.
Remarks on result:
other: see Remark
Remarks:
Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 100%. No with. + reactions: 0.0. Total no. in groups: 20.0. Clinical observations: very faint to moderate erythema was noted at all test sites during the induction phase. Desquamation was noted at a few test sites following the seventh through ninth inductions..
Reading:
2nd reading
Hours after challenge:
48
Group:
test group
Dose level:
100%
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%. No with. + reactions: 0.0. Total no. in groups: 20.0.
Reading:
1st reading
Hours after challenge:
24
Group:
positive control
Dose level:
75%
No. with + reactions:
3
Total no. in group:
10
Remarks on result:
other: Reading: 1st reading. . Hours after challenge: 24.0. Group: positive control. Dose level: 75%. No with. + reactions: 3.0. Total no. in groups: 10.0.
Reading:
2nd reading
Hours after challenge:
48
Group:
positive control
Dose level:
75%
No. with + reactions:
3
Total no. in group:
10
Remarks on result:
other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: positive control. Dose level: 75%. No with. + reactions: 3.0. Total no. in groups: 10.0.
Reading:
1st reading
Hours after challenge:
24
Group:
negative control
Dose level:
n/a
No. with + reactions:
0
Total no. in group:
10
Remarks on result:
other: Reading: 1st reading. . Hours after challenge: 24.0. Group: negative control. Dose level: n/a. No with. + reactions: 0.0. Total no. in groups: 10.0.
Reading:
2nd reading
Hours after challenge:
48
Group:
negative control
Dose level:
n/a
No. with + reactions:
0
Total no. in group:
10
Remarks on result:
other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: negative control. Dose level: n/a. No with. + reactions: 0.0. Total no. in groups: 10.0.

Applicant's summary and conclusion

Interpretation of results:
not sensitising
Remarks:
Migrated information Criteria used for interpretation of results: EU
Conclusions:
The test material was found to not be sensitising to skin in the Buehler method. The study was conducted according to OECD TG 406 and in compliance with GLP.
Executive summary:

A Buehler test was conducted in guinea pigs, to determine the sensitisation potential of the test material after repeated topical applications. The undiluted substance was applied topically, on the skin of 20 healthy guinea pigs, three times a week, for a three week induction period. Nine days after the first induction dose, a challenge dose of the test substance at its highest non-irritating concentration (100%) was applied to a naive site on each guinea pig. Approximately 24 and 48 hours after induction and challenge dose, the animals were scored for erythema. A similar induction and challenge application regimen with HCA in mineral oil was followed using an additional ten guinea pigs that served as concurrent positive controls for the study. Two naive control groups were maintained under identical environmental conditions and treated with the test or the positive control substance at challenge only. None of the 20 test animals showing showed reactions, so based on the result of the study the substance was not considered to be a skin sensitiser.