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:
5th March 1993 to 25th June 1993
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Comparable to guideline studies with restrictions. Information relating to the test animals, exposure and test system were not described in the main body of the report but were given in the protocol only.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1993
Report Date:
1993

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 406 (Skin Sensitisation)
Deviations:
no
Qualifier:
according to
Guideline:
EU Method B.6 (Skin Sensitisation)
Deviations:
no
Qualifier:
according to
Guideline:
EPA OTS 798.4100 (Skin Sensitisation)
Deviations:
no
GLP compliance:
yes (incl. certificate)
Type of study:
guinea pig maximisation test
Justification for non-LLNA method:
No new study has been conducted, data from 1993

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
Purity: 97.3%
Batch No.: 9236-23

In vivo test system

Test animals

Species:
guinea pig
Strain:
Hartley
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS (information provided in the study protocol)
- Source: Charles River, France
- Age at study initiation: young adult (about 6 weeks old)
- Weight at study initiation: 383-449 g (males); 354-413 g (females)
- Housing: Animals were housed in groups according to EEC/86/609 in stainless steel mesh cages (internal dimensions 500 x 600 x 200 mm).
- Diet (e.g. ad libitum): Pelleted complete guinea-pig diet available ad libitum (Diet reference 114 C - Usine d'Alimentation Rationnelle, Villemoisson, 91360 Epinay-sur-Orge, FRANCE)
- Water (e.g. ad libitum): Softened and filtered 0.2 µm mains drinking water available ad libitum (via automatic system)
- Acclimation period: At least 5 days

ENVIRONMENTAL CONDITIONS (information provided in the study protocol)
- Temperature (°C): 19 ± 3 °C
- Humidity (%): Minimum 44.9%
- Air changes (per hr): > 22 air changes per hour
- Photoperiod: 12 hours light (artificial)/12 hours dark

IN-LIFE DATES: Not specified

Study design: in vivo (non-LLNA)

Inductionopen allclose all
Route:
intradermal and epicutaneous
Vehicle:
other: Absolute ethanol
Concentration / amount:
Concentration of test material and vehicle used at induction:
Test article in a 0.1 % (w/w) suspension in abs. ethanol.

Concentration of test material and vehicle used for each challenge:
Test article in a 50 % (w/w) paste in absolute ethanol.
Challengeopen allclose all
Route:
epicutaneous, occlusive
Vehicle:
other: Absolute ethanol
Concentration / amount:
Concentration of test material and vehicle used at induction:
Test article in a 0.1 % (w/w) suspension in abs. ethanol.

Concentration of test material and vehicle used for each challenge:
Test article in a 50 % (w/w) paste in absolute ethanol.
No. of animals per dose:
Number of animals in test group: 20
Number of animals in negative control group: 10
Details on study design:
RANGE FINDING TESTS: Not performed


MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures:
INTRADERMAL ROUTE: 3 series of 2 x 0.1 mL injections:
* Freund's complete adjuvant at 50% (v/v) in an isotonic injectable solution;
* test article in a 0.1% (w/w) suspension in absolute ethanol
* mixture 50/50 (v/v) : test article in a 0.2% (w/w) suspension in absolute ethanol + Freund's complete adjuvant at 50% (v/v) in an isotonic injectable solution, i.e. a final 0.1% concentration of the test article
TOPICAL OCCLUSIVE ROUTE: Treatment with 0.5 mL of the test article in a 50% (w/w) paste in absolute ethanol.
- Exposure period: Exposure by the topical occlusive route was for a period of 48 hours.
- Test groups: One treated group of 20 animals (male and female)
- Control group: One control group of 10 animals were treated with the vehicle only during induction. The intradermal injections and the topical occlusive application for 48 hours were carried out under the same conditions as in the treated group, absolute ethanol replacing the test article.
- Site: Topical application of the test material was applied to an area of 8 cm2 on the back of the animal (clipped skin).
- Frequency of applications: Not applicable (only 1 injection of the test material was administered).
- Duration: Topical application: 48 h
- Concentrations: Test article in a 0.1 % (w/w) suspension in abs. ethanol.

The rest period was 11 days without treatment.

B. CHALLENGE EXPOSURE
- No. of exposures: During the "challenge", topical occlusive application for 24 hours was performed in the treated group and in the control group with the test article in a 50% (w/w) paste in absolute ethanol and at the dose level of 0.5 mL (Maximum Non-irritant Concentration : M.N I.C.). The vehicle was also applied during the challenge.
- Day(s) of challenge: Day 22-24
- Exposure period: 24 h
- Test groups: The treated group and in control group used in the induction phase.
- Control group: The control group used in the induction phase was treated with the test material during the challenge exposure.
- Site: Occlusive topical application, for 24 hours to an area of 4 cm2, of 0.5 ml of the test article at the Maximum Non Irritant Concentration (M N.I.C.) (left flank) and of the vehicle (right flank).
- Concentrations: Test article in a 50% (w/w) paste in absolute ethanol
- Evaluation (hr after challenge): The cutaneous macroscopic examinations were performed according to the Magnusson & Kligman scale and to the challenge application site, 24 and 48 hours after removal of the patches.
Challenge controls:
The control animals used during the induction phase were treated with test material during the challenge.
Positive control substance(s):
no

Results and discussion

Positive control results:
Not applicable

In vivo (non-LLNA)

Resultsopen allclose all
Reading:
1st reading
Hours after challenge:
24
Group:
test group
Dose level:
50 %
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: 50 %. No with. + reactions: 0.0. Total no. in groups: 20.0.
Reading:
2nd reading
Hours after challenge:
48
Group:
test group
Dose level:
50 %
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: 50 %. No with. + reactions: 0.0. Total no. in groups: 20.0.
Reading:
1st reading
Hours after challenge:
24
Group:
negative control
Dose level:
50 %
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: 50 %. No with. + reactions: 0.0. Total no. in groups: 10.0.
Reading:
2nd reading
Hours after challenge:
48
Group:
negative control
Dose level:
50 %
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: 50 %. No with. + reactions: 0.0. Total no. in groups: 10.0.
Group:
positive control
Remarks on result:
not measured/tested

Any other information on results incl. tables

Induction phase: Injection of the test article in a 0.1% suspension provoked a moderate to severe irritation with a burnt aspect to the injection site during the preliminary study.

Exposure by the topical occlusive route for 48 hours provoked a weak to moderate irritation during the preliminary study; therefore, no skin painting with 0.5 mL of sodium lauryl sulphate at 10% (w/w) in Codex paraffin was performed on Day 8.

Signs of irritation were noted during induction in the treated group.

Challenge phase: The macroscopic examinations did not reveal any lesion of delayed hypersensitivity in the 20 treated animals. No cutaneous abnormality was noted in the 10 guinea-pigs examined in the control group.

From the results obtained under the experimental conditions employed, the test article did not provoke any reaction of cutaneous sensitization in the animals examined.

Maximum concentration not causing irritating effects in preliminary test: 50 %

Signs of irritation during induction:
Yes

Evidence of sensitisation of each challenge concentration:
None

Applicant's summary and conclusion

Interpretation of results:
not sensitising
Conclusions:
The test material, Millad 3988, did not provoke any reaction of cutaneous sensitization in the animals examined.
Executive summary:

The test material, Millad®3988, was evaluated for its sensitising potential in guinea pigs. The results obtained under the experimental conditions employed demonstrated that the test material did not provoke any reaction of cutaneous sensitization in the animals examined.

The macroscopic examinations did not reveal any lesion of delayed hypersensitivity in the 20 treated animals. No cutaneous abnormality was noted in the 10 guinea-pigs examined in the control group.