Registration Dossier

Toxicological information

Skin sensitisation

Currently viewing:

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: The study was conducted according to an appropriate OECD guideline and in compliance with GLP.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2004
Report Date:
2004

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)
GLP compliance:
yes
Type of study:
mouse local lymph node assay (LLNA)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent

In vivo test system

Test animals

Species:
mouse
Strain:
CBA
Sex:
female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: B&K Universal Ltd., Hull, Uk
- Age at study initiation: 8-12 weeks
- Weight at study initiation: 15-23 g
- Housing: individually housed
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: minimum 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19-20
- Humidity (%): 30-70
- Air changes (per hr): ca. 15
- Photoperiod (hrs dark / hrs light): 12/12

Study design: in vivo (LLNA)

Vehicle:
acetone/olive oil (4:1 v/v)
Concentration:
undiluted
25% or 50% v/v in acetone/olive oil 4:1
No. of animals per dose:
4 animals per test group
Details on study design:
The mice were treated by application of 25 microlitres of the appropriate concentration of the test material to the dorsal surface of each ear for three consecutive days (days 0, 1, 2). A further group of 4 mice received the vehicle alone in the same manner.

Five days following the first topical application of the test material (day 5) all mice were injected via the tail vein with 250 microlitres of phosphate buffered saline containing a radiolabel. Five hours after that, all mice were killed. The draining auricular lymph nodes from the four mice were excised and pooled for each experimental group.

The proliferation response of lymph node cells was expressed as the number of radioactive disintegrations per minute per lymph node, relative to that recorded for control nodes.
If a threefold increase compared to control values was recorded, the substance was considered a sensitiser.
Positive control substance(s):
hexyl cinnamic aldehyde (CAS No 101-86-0)

Results and discussion

Positive control results:
The positive control substance (25% hexyl cinnamic aldehyde in acetone/olive oil 4:1) was considered to be a sensitiser in a study conducted in March 2003.

In vivo (LLNA)

Resultsopen allclose all
Parameter:
SI
Value:
0.9
Test group / Remarks:
25% v/v; 4 mice, strain CBA/Ca
Parameter:
SI
Value:
3.6
Test group / Remarks:
50% v/v; 4 mice, strain CBA/Ca
Parameter:
SI
Value:
4.6
Test group / Remarks:
100% v/v; 4 mice, strain CBA/Ca
Parameter:
SI
Value:
5.5
Test group / Remarks:
The positive control substance was considered to be a sensitiser in a study conducted in March 2003
Parameter:
other: disintegrations per minute (DPM)
Remarks on result:
other: see Remark
Remarks:
Vehicle 8425.12 Dpm, 1053.1 Dpm/node 25% 7802.73 Dpm 975.3 Dpm/node (negative) 50% 30366.88 Dpm 3795.8 Dpm/node (positive) 100% 39088.36 Dpm 4886 Dpm/node (positive)

Any other information on results incl. tables

A stimulation index of >3 was recorded for the two higher concentrations of test material (50% v/v and 100%). A stimulation index of <3 was recorded for the lowest concentration of the test material (25% v/v). There were no deaths. No signs of systemic toxicity were noted in the test or control animals during the study.

Applicant's summary and conclusion

Interpretation of results:
Category 1B (indication of skin sensitising potential) based on GHS criteria
Conclusions:
The test material was considered to be a sensitiser under the conditions of the test. A stimulation index of >3 was recorded for the two higher concentrations of test material (50% v/v and 100%), relative to the negative controls.