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)

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2007
Report Date:
2007

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)
Version / remarks:
and EEC Methods for the determination of toxicity. Annex to Commission Directive 2004/73/EC (Official Journal No. L152, 30.4.2004), Part B, Method B.42.
Deviations:
no
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:
concentrations of 10, 25 and 50% v/v in Acetone : Olive Oil (4:1 v/v)
No. of animals per dose:
four

Results and discussion

Positive control results:
Positive control study with hexyl cinnamic aldehyde using the local lymph node assay (Study No. HLS/0521). This study was performed to confirm the sensitivity and reliability of the experimental technique used at Huntingdon Life Sciences to detect skin sensitization potential. The study was performed using the murine local lymph node assay and a known moderate sensitizer - hexyl cinnamic aldehyde (HCA) [Technical grade 90.6%] supplied by Aldrich Chemical Co, England (Batch No. 13102MO, Expiry 13 June 2007).

This positive control study was conducted between 24 May and 6 June 2007 using sixteen mice of the CBA/Ca strain supplied by Harlan UK Ltd., Bicester, Oxon, England. Groups of four mice were used in this study. Three dosage levels and a vehicle control were used with dosages of HCA selected based on previous experience with HCA at this laboratory as follows: 10, 25 and 50% v/v in AOO (4:1 v/v acetone:olive oil)
The positive control study is considered to be valid if at least one concentration of HCA results in a threefold greater increase in 3H-methyl thymidine (3HTdR) incorporation compared to control values.

In vivo (LLNA)

Results
Parameter:
SI
Remarks on result:
other: see Remark
Remarks:
Results for each treatment group were expressed as the stimulation index. This was obtained by comparing the proliferation in the vehicle treated control group with the values from the three test groups as follows: the ratio of 3HTdR incorporation into lymph node cells, expressed as dpm, relative to that recorded for control lymph nodes is derived for each test group based on the group mean dpm per node. When the stimulation index ≥3, the test substance is regarded as a skin sensitizer.

Applicant's summary and conclusion

Interpretation of results:
other: Potentially weak skin sensitizer
Conclusions:
Trimofix O is regarded as a potential weak skin sensitizer, at the concentration of 25%, with an EC3 value of 20.71. (Kimber et al, 2003).
Executive summary:

Trimofix O is regarded as a potential weak skin sensitizer, at the concentration of 25%, with an EC3 value of 20.71. (Kimber et al, 2003).