Registration Dossier

Administrative data

Endpoint:
skin sensitisation: in vivo (LLNA)
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Study was performed according to the recommended guidelines and GLP. There were minor deviations from the protocol which did not adversely affect the study integrity.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2008
Report Date:
2008

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)
Deviations:
yes
Remarks:
Minor deviations from the protocol which did not adversely affect the study integrity.
Qualifier:
according to
Guideline:
EU Method B.42 (Skin Sensitisation: Local Lymph Node Assay)
Qualifier:
according to
Guideline:
EPA OPPTS 870.2600 (Skin Sensitisation)
GLP compliance:
yes
Type of study:
mouse local lymph node assay (LLNA)

Test material

Reference
Name:
Unnamed
Type:
Constituent

In vivo test system

Test animals

Species:
mouse
Strain:
CBA
Sex:
female

Study design: in vivo (LLNA)

Vehicle:
acetone/olive oil (4:1 v/v)
Concentration:
25%, 50% and 100%
No. of animals per dose:
5 animals per dose
Positive control substance(s):
hexyl cinnamic aldehyde (CAS No 101-86-0)

Results and discussion

Positive control results:
The SI values calculated for Alpha-Hexylcinnamaldehydeat concentrations 5, 10 and 25% were 1.0, 2.0 and 5.7 respectively. An EC3 value of 14.1% was calculated using linear interpolation.

The calculated EC3 value was found to be in the acceptable range of 2 and 20%. The results of the 6 monthly HCA reliability checks of the recent years were 10.3, 9.5, 13.1 and 15.6%.

Based on the results, it was concluded that the Local Lymph Node Assay as performed in this study is an appropriate model for testing for contact hypersensitivity.

In vivo (LLNA)

Resultsopen allclose all
Parameter:
SI
Remarks on result:
other: The SI values calculated for the substance concentrations 25, 50 and 100% were 9.5, 12.6 and 15.0 respectively.
Parameter:
other: disintegrations per minute (DPM)
Remarks on result:
other: Mean DPM/animal values for the experimental groups treated with test substance concentrations 25, 50 and 100% were 6958, 9254 and 11040 respectively. The mean DPI/animal value for the vehicle control group was 736.

Applicant's summary and conclusion

Interpretation of results:
sensitising
Remarks:
Migrated information
Conclusions:
The SI values calculated for the substance concentrations 25, 50 and 100% were 9.5, 12.6 and 15.0 respectively.

These results show that the test substance elicits an SI > 3. The EC3 value was established to be between 0 and 25%.
No reliable EC3 value could be calculated. It was possible to strengthen the outcome of the study by adding lower concentrations. Since the SI values clearly exceeded 3 and since extension of the study would not alter the classification, this was considered not appropriate for ethical reasons.

The six monthly reliability check with Hexylcinnamaldehyde, indicates that the Local Lymph Node Assay as performed in this study is an appropriate model for testing for contact hypersensitivity.

There were minor deviations from the protocol which did not adversely affect the study integrity; validity criteria have been fulfilled.

Based on these results:
- according to the recommendations made in the test guidelines, the test substance would be regarded as skin sensitizer.

- according to the Globally Harmonized System of Classification and Labeling of Chemicals (GHS) of the United Nations (2004), the test substance should be classified as skin sensitizer (Category 1).

- according to the EC criteria for classification and labeling requirements for dangerous substances and preparations (Council Directive 67/548/EEC), the test substance should be labeled as: may cause sensitization by skin contact (R 43).