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:
Not reported
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1982
Report Date:
1982

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 406 (Skin Sensitisation)
Deviations:
not specified
Principles of method if other than guideline:
The method employed in this study for the detection of delayed contact hypersensitivity was the guineo-pig maximization test described by Magnusson B and Kligman AM (1970) in "Allergic Contact Dermatitis in the Guinea-Pig: Identification of contact allergens", published by C. C. Thomas, Springfield, Illinois, U. S.A.
GLP compliance:
not specified
Type of study:
guinea pig maximisation test
Justification for non-LLNA method:
A valid GMPT study was available before REACH came into force, therefore no additional LLNA study was conducted.

Test material

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

In vivo test system

Test animals

Species:
guinea pig
Strain:
Pirbright-Hartley
Sex:
female
Details on test animals and environmental conditions:
TEST ANIMALS
- Average weight at study initiation: 440 g

Study design: in vivo (non-LLNA)

Induction
Route:
intradermal
Vehicle:
other: Propylene glycol
Concentration / amount:
induction: Intradermal injection - Site 1) 0.1 ml Freund's adjuvant; site 2) 0.1 ml of a 5% solution of test substance in propylene glycol; site 3) 0.1 ml of a 1:1 mix of Freund's adjuvant and 5% test substance solution
Challenge: After 1 week, 5% test substance in vaseline (occlusive patch for 48 h); after 14 days 25% test substance in vaseline (open application)
Challenge
Route:
epicutaneous, occlusive
Vehicle:
other: Propylene glycol
Concentration / amount:
Induction: Intradermal injection - Site 1) 0.1 ml Freund's adjuvant; site 2) 0.1 ml of a 5% solution of test substance in propylene glycol; site 3) 0.1 ml of a 1:1 mix of Freund's adjuvant and 5% test substance solution
Challenge: After 1 week, 5% test substance in vaseline (occlusive patch for 48 h); after 14 days 25% test substance in vaseline (open application)
No. of animals per dose:
20
Details on study design:
MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: 1
- Test groups: 20
- Control group: 20
- Site: both sites of the spinal cord at the level of the shoulder blades

B. CHALLENGE EXPOSURE
- No. of exposures: once, one week after induction, then again 14 days later (re-challenge)
- Exposure period: after one week; exposure over the injection sites via occlusive patch for 48 h; after 14 days: open application on right flank
- Evaluation (h after challenge): Animals observed after induction and challenge, up until 72 h after re-challenge (at 14 days)
Challenge controls:
Identical to test group.
Positive control substance(s):
no

Results and discussion

Positive control results:
Intracutaneous application of Freund's adjuvant caused strong skin reddening, skin swelling and later necrosis and scarring

In vivo (non-LLNA)

Resultsopen allclose all
Key result
Reading:
other: After removal of the occlusive patch
Hours after challenge:
48
Group:
test group
Dose level:
5% test substance in vaseline
No. with + reactions:
0
Total no. in group:
20
Clinical observations:
No specific skin reactions
Key result
Reading:
rechallenge
Hours after challenge:
24
Group:
test group
Dose level:
25% test substance in vaseline
No. with + reactions:
0
Total no. in group:
20
Clinical observations:
None
Key result
Reading:
rechallenge
Hours after challenge:
24
Group:
negative control
Dose level:
0% test substance
No. with + reactions:
0
Total no. in group:
20
Clinical observations:
None
Reading:
rechallenge
Group:
positive control
Remarks on result:
not measured/tested

Applicant's summary and conclusion

Interpretation of results:
other: CLP criteria not met
Remarks:
(non-sensitising)
Conclusions:
Under the study conditions, the test substance did not produce any evidence of delayed contact hypersensitivity and was therefore considered non-sensitizing.
Executive summary:

A study was performed to determine the delayed contact hypersensitivity potential of the test substance, C8-18 and C18-unsatd. DEA, in 20 female Pilbright guinea-pigs, according to OECD Guideline 406 (GPMT: guinea pig maximisation test). The procedure consisted of two parts: induction and challenge exposures. For induction, three sets of intradermal injections were given (0.1 ml Freund's adjuvant; 0.1 ml of a 5% solution of test substance in propylene glycol, and 0.1 ml of a 1:1 mix of Freund's adjuvant and 5% test substance. One week after the injections, a 5% test solution was placed on the skin over the injection sites via an occlusive patch and left for 48 h. This was followed by a re-challenge: 14 d after the cutaneous exposure, 25% test substance in vaseline was placed on the skin of the right flank (open application). Under the study conditions, the test substance did not produce any evidence of delayed contact hypersensitivity and was therefore considered non-sensitizing (Potokar, 1982).