Registration Dossier

Toxicological information

Skin sensitisation

Currently viewing:

Administrative data

Endpoint:
skin sensitisation: in vivo (non-LLNA)
Type of information:
experimental study
Adequacy of study:
key study
Study period:
03 Dec 1999 - 04 Feb 2000
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2000
Report Date:
2000

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 406 (Skin Sensitisation)
Version / remarks:
adopted 17 Jul 1992
Deviations:
no
Qualifier:
according to
Guideline:
EU Method B.6 (Skin Sensitisation)
Version / remarks:
1996
Deviations:
no
GLP compliance:
yes (incl. certificate)
Remarks:
THE DEPARTMENT OF HEALTH OF THE GOVERNMENT OF THE UNITED KINGDOM
Type of study:
guinea pig maximisation test
Justification for non-LLNA method:
The test was done before LLNA as first-choice method for in-vivo testing was set into force.

Test material

Reference
Name:
Unnamed
Type:
Constituent

In vivo test system

Test animals

Species:
guinea pig
Strain:
Dunkin-Hartley
Sex:
female
Details on test animals and environmental conditions:
TEST ANIMALS
- Age at study initiation: approx. 8-12 weeks
- Weight at study initiation: 344-388 g
- Housing: animals were housed singly or in pairs in solid-floor polypropylene cages, bedding woodflakes
- Diet: Guinea Pig FD1 Diet (Special Diets Services LTD, Witham, UK), ad libitum
- Water: mains tap water, ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 17-23
- Humidity (%): 30-70
- Air changes (per hr): approx. 15
- Photoperiod (hrs dark / hrs light): 12/12

Study design: in vivo (non-LLNA)

Inductionopen allclose all
Route:
intradermal
Vehicle:
arachis oil
Concentration / amount:
1%
Day(s)/duration:
single injection
Adequacy of induction:
highest concentration used causing mild-to-moderate skin irritation and well-tolerated systemically
Route:
epicutaneous, occlusive
Vehicle:
unchanged (no vehicle)
Concentration / amount:
100%
Day(s)/duration:
48 h
Adequacy of induction:
highest concentration used causing mild-to-moderate skin irritation and well-tolerated systemically
Challengeopen allclose all
No.:
#1
Route:
epicutaneous, occlusive
Vehicle:
arachis oil
Concentration / amount:
75%
Day(s)/duration:
24 h
Adequacy of challenge:
other: non-irritant concentration
No.:
#1
Route:
epicutaneous, occlusive
Vehicle:
unchanged (no vehicle)
Concentration / amount:
100%
Day(s)/duration:
24 h
Adequacy of challenge:
highest non-irritant concentration
No. of animals per dose:
5 (controls), 10 (test group)
Details on study design:
RANGE FINDING TESTS:
A range finding study was performed to determine the appropriate dose level of the test substance following intradermal and epicutaneous administrations. For the selection of the intradermal induction concentration test substance concentrations of 1 and 5% were investigated. A total of two animals were used, each animal receiving four injections of only one concentration of test substance. Moderate and confluent erythema (score 2) was observed 24 and 48 h and discrete or patchy erythema (score 1) was observed 72 h after treatment with 1% test substance concentration. Moderate and confluent erythema to intense erythema and swelling (score 2-3) was observed after 24 and 48 h and discrete or patchy erythema (score 1) was observed 72 h after treatment with 5% test substance concentration. The effects were fully reversible within 7 days. No evidence of systemic toxicity was observed. The concentration selected for the intradermal induction stage of the main study was 1%.
For the selection of the topical induction concentration two animals (intradermally injected with FCA nine days earlier) were treated 48 h with undiluted test substance and three preparations of the test substance (25, 50 and 75%). Moderate and confluent erythema (score 2) was observed 1 h after patch removal in two animals at 75 and 100%. Discrete or patchy erythema (score 1) was observed only in one animal 1 h after patch removal at 50%. Discrete or patchy erythema (score 1) was observed at 75 and 100% in one animal and at 50, 75 and 100% in the second animal 24 h after patch removal. Only discrete or patchy erythema (score 1) was observed in one animal 48 h after patch removal at 100%. No oedema was observed up to the highest concentration tested. The undiluted test substance was selected for the main study topical induction.
For the selection of the topical challenge concentration two animals (identically treated to the control animals of the main study up to Day 14) were treated with undiluted test substance and three preparations of the test substance (25, 50 and 75) under occlusive conditions for 24 h. Only discrete or patchy erythema (score 1) was observed 1 h after removal of the dressing at 100% in two animals. No oedema was observed up to the highest concentration tested. The concentrations selected for the main study topical challenge were 75 and 100%.

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: 2 (intradermal and epicutaneous, respectively)
- Exposure period: single injection (intradermal) and 48 h (epicutaneous)
- Test groups:
Intradermal (3 pairs of injections):
Injection 1: a 1:1 mixture FCA/water
Injection 2: 1% test substance in arachis oil
Injection 3: equal amounts of 1% test substance and FCA
Epicutaneous: undiluted test substance
- Control group:
Injection 1: a 1:1 mixture FCA/water
Injection 2: arachis oil
Injection 3: equal amounts of 50% arachis oil and FCA
Epicutaneous: black filter paper
- Site: shoulder region (intradermal + epicutaneous)
- Duration: Days 0-7
- Concentrations: intradermal 1%, epicutaneous 100%

B. CHALLENGE EXPOSURE
- No. of exposures: 1 (challenge)
- Day of challenge: 21 (challenge)
- Exposure period: 24 h
- Test groups: undiluted test substance and 75% test substance in arachis oil
- Control group: undiluted test substance and 75% test substance in arachis oil
- Site: right flank (100% test substance) and left flank (75% test substance)
- Concentrations: 75 and 100%
- Evaluation: 24 and 48 h after patch removal
Challenge controls:
The control group is actually a challenge control.
Positive control substance(s):
yes
Remarks:
2-mercaptobenzothiazole, Induction: intradermal 5% in arachis oil, epicutaneous 50% in acetone:PEG 400 (70:30), Challenge: 25 and 50% in acetone:PEG 400 (70:30)

Results and discussion

Positive control results:
The positive control substance induced positive reactions in 10/10 animals (100%). The positive control group was not carried out concurrently with this study but is a historical background data group from a study performed during 12 Jan and 05 Feb 2000.

In vivo (non-LLNA)

Resultsopen allclose all
Reading:
1st reading
Hours after challenge:
24
Group:
negative control
Dose level:
Induction intradermal: 0%; challenge: 75%
No. with + reactions:
0
Total no. in group:
4
Clinical observations:
One animal was found dead on Day 20.
Reading:
1st reading
Hours after challenge:
24
Group:
negative control
Dose level:
Induction intradermal: 0%; challenge: 100%
No. with + reactions:
0
Total no. in group:
4
Clinical observations:
One animal was found dead on Day 20.
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
test group
Dose level:
Induction intradermal: 1%; challenge: 75%
No. with + reactions:
0
Total no. in group:
10
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
test group
Dose level:
Induction intradermal: 1%; challenge: 100%
No. with + reactions:
0
Total no. in group:
10
Reading:
2nd reading
Hours after challenge:
48
Group:
negative control
Dose level:
Induction intradermal: 0%; challenge: 75%
No. with + reactions:
0
Total no. in group:
4
Clinical observations:
One animal was found dead on Day 20.
Reading:
2nd reading
Hours after challenge:
48
Group:
negative control
Dose level:
Induction intradermal: 0%; challenge: 100%
No. with + reactions:
0
Total no. in group:
4
Clinical observations:
One animal was found dead on Day 20.
Key result
Reading:
2nd reading
Hours after challenge:
48
Group:
test group
Dose level:
Induction intradermal: 1%; challenge: 75%
No. with + reactions:
0
Total no. in group:
10
Key result
Reading:
2nd reading
Hours after challenge:
48
Group:
test group
Dose level:
Induction intradermal: 1%; challenge: 100%
No. with + reactions:
0
Total no. in group:
10
Reading:
1st reading
Hours after challenge:
24
Group:
positive control
Dose level:
50% in acetone:PEG 400 (70:30), Challenge: 25 and 50% in acetone:PEG 400 (70:30)
No. with + reactions:
10
Total no. in group:
10
Clinical observations:
none

Any other information on results incl. tables

Discrete or patchy to moderate and confluent erythema was noted at the intradermal induction sites of all test group animals after 24 h and with discrete or patchy to intense erythema and swelling after 48 h.

Discrete or patchy erythema was noted at the intradermal induction sites of all control group animals after 24 h and in two control group animals after 48 h.

Discrete or patchy erythema was noted at the induction sites of seven test group animals after 1 h and in four test group animals after 24 h. Bleeding from the intradermal injection sites was noted in four test group animals after 1h.

Bleeding from the intradermal injection sites was noted in four control group animals after 1h. No signs of erythema or oedema were noted at the treatment sites of control group animals after 24 h.

No skin reactions were noted at the challenge sites of the test or control group animals after 24 and 48 h.

Body weight gains of animals in the test group, between Day 0 and Day 24, were comparable to those observed in the control group animals over the same period.

One control group animal was found dead on Day 20. The cause of death was not determined but was thought not to be treatment-related. The absence of this animal was considered not to affect the purpose or integrity of the study.

Applicant's summary and conclusion

Interpretation of results:
other: CLP/EU GHS criteria not met, no classification required according to Regulation (EC) No 1272/2008
Conclusions:
Under the conditions of the guinea pig maximisation test the test substance revealed no sensitising properties.
Executive summary:

Ten test and five control animals were used for the main study. Based on the results of sighting tests, the concentrations of test material for the induction and challenge phases were selected as follows: Intradermal Induction 1% v/v in arachis oil BP; Topical Induction undiluted as supplied; Topical Challenge undiluted as supplied and 75% v/v in arachis oil BP. The test material produced a 0% (0/10) sensitisation rate.