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Administrative data

Description of key information

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records
Reference
Endpoint:
skin sensitisation: in vivo (LLNA)
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2006
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP/Guideline Study
Reason / purpose:
reference to same study
Qualifier:
according to
Guideline:
OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)
Deviations:
no
Qualifier:
according to
Guideline:
EU Method B.42 (Skin Sensitisation: Local Lymph Node Assay)
Deviations:
no
Qualifier:
according to
Guideline:
EPA OPPTS 870.2600 (Skin Sensitisation)
Deviations:
no
GLP compliance:
yes
Type of study:
mouse local lymph node assay (LLNA)
Species:
mouse
Strain:
CBA
Sex:
female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Charles River France, L'Arbresle Cedex, France
- Age at study initiation: Approximately 10 weeks old
- Housing: groups housed in Macrolon cages
- Diet (e.g. ad libitum): Free access to standard pelleted laboratory diet (from Altromin (code VRF 1), Lage, Germany)
- Water (e.g. ad libitum): Free access to tap water
- Acclimation period: 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18.8-23.5°C
- Humidity (%): 33-77%
- Air changes (per hr): 15
- Photoperiod (hrs dark / hrs light): 12/12

Route:
epicutaneous, open
Vehicle:
propylene glycol
Concentration / amount:
50, 100%
Concentration / amount:
50, 100%
No. of animals per dose:
1
Vehicle:
propylene glycol
Concentration:
5%, 25%, and 50% of test substance
No. of animals per dose:
5
Details on study design:
Three groups of five experimental animals were treated with test substance concentrations of
5%, 25% or 50% on three consecutive days, by open application on the ears. Five vehicle control animals were
similarly treated, but with vehicle alone (Propylene glycol). Three days after the last exposure, all animals were
injected with 3H-methyl thymidine and after five hours the draining (auricular) lymph nodes were excised.
After precipitating the DNA of the lymph node cells, radioactivity measurements were performed. The activity
was expressed as the number of Disintegrations Per Minute (DPM) and a stimulation index was subsequently
calculated for each group.
Positive control substance(s):
hexyl cinnamic aldehyde (CAS No 101-86-0)
Statistics:
DPM values are presented for each animal and for each dose group. A Stimulation Index (SI) is calculated for each group. The SI is the ratio of the DPM/group compared to DPM/vehicle control group.
Positive control results:
The six month reliability chech with Hexylcinnamic aldehyde indicates that the Local Lymph Node Assay as performed at NOTOX is an appropriate
model for testing for contact hypersensitivity.
Parameter:
SI
Remarks on result:
other: see Remark
Remarks:
The SI values for the substance concentrations 5, 25, and 50% were 7.6, 48.0, and 54.2 respectively. These results show that the test substance elicited an SI ≥ 3. The data showed a dose-response and the EC3 value was established to be between 0 and 5%
Parameter:
other: disintegrations per minute (DPM)
Remarks on result:
other: Mean DPM/animal values for the experimental groups treated with test substance concentrations 5, 25, and 50% were 1484, 9339, and 10539 respectively. The mean DPM/animal value for the vehicle control group was 195.

TABLE 1: SKIN REACTIONS AFTER 3RD INDUCTION AND RELATIVE SIZE NODES

 Day 3

 Day 6

 Group  Animal    skin grading dorsal surface ear       

   size nodes 

 Treatment  Number     left     right  left  right
     erythema  oedema  erythema  oedema    
 1  1  0  0  0  0  n  n
 Vehicle*  2  0  0  0  0  n  n
 Control  3  0  0  0  0  n  n
   4  0  0  0  0  n  n
   5  0  0  0  0  n  n
               
 2  6  1  0  1  0  n  n
 5% test  7  0  0  1  0  n  n
 substance  8  0  0  0  0  n  n
   9  0  0  0  0  n  n
   10  1  0  0  0  n  n
               
 3  11  1  0  2  0  +  +
 25% test  12  1  0  1  0  +  +
 substance  13  1  0  1  0  +  +
   14  1  0  1  0  +  +
   15  1  0  1  0  +  +
               
 4  16  1  0  1  0  ++  ++
 50% test  17  2  0  2  0  ++  ++
 substance  18  1  0  2  0  +  ++
   19  2  0  2  0  ++  ++
   20  1  0  2  0  +  ++

n: considered to be normal

+: enlarged

* Vehicle: Propylene glycol

Interpretation of results:
sensitising
Remarks:
Migrated information Criteria used for interpretation of results: EU
Conclusions:
According to the Globally Harmonized System of Classification and Labeling of Chemicals (GHS) of the United Nations (New York and Geneva, 2003), Unoxol 3,4 Dialdehyde should be classifed as a skin sensitizer (Category 1).
Executive summary:

In the main study, three groups of five experimental animals were treated with test substance concentrations of 5%, 25%, or 50% on three consecutive days, by an open application on the ears. Five vehicle control animals were similarly treated, but with vehicle alone(Propylene glycol). Three days after the last exposure, all animals were injected with 3H-methyl thymidine and after five hours the draining (auricular) lymph nodes were excised. After precipitating the DNA of the lymph node cells, radioactivity measurements were performed. The activity was expressed as the number of Disintegrations Per Minute (DPM) and a stimulation index was subsequently calculated for each group.

Mean DPM/animal values for the experimental groups treated with test substance concentrations 5, 25, and 50% were 1484, 9339 and 10539 respectively. The mean DPM/animals value for the vehicle control group was 195.

The SI values calculated for the substance concentrations 5, 25, and 50% were 7.6, 48.0, and 54.2 respectively.

The results show that the test substance elicited an SRI ≥ 3. The data showed a dose-response and the EC3 value was established to be between 0 and 5%.

The six month reliability check with Hexylcinnamic aldehyde indicates that the Local Lymph Node Assay as performed at NOTOX is an appropriate model for testing for contact hypersensitivity. Based on these results:

- according to the recommendations make in the test guidelines, Unoxol 3,4 Dialdehyde would be regarded as a skin sensitizer.

- according to the globally Harmonized System of Classification and Labeling of Chemicals (GHS) of the United Nations (New York and Geneva, 2003), Unoxol 3,4 Dialdehyde should be classified as a skin sensitizer (Category 1).

- according to the EC criteria for classification and labeling requirements for dangerous substances and preparations (Council Directive 67/548/EEC) Unoxol 3,4 Dialdehyde should be labeled as: may cause sensitization by skin contact (R 43).

Endpoint conclusion
Endpoint conclusion:
adverse effect observed (sensitising)
Additional information:

A standard guideline LLNA study was performed on this substance. In the main study, three groups of five experimental animals were treated with test substance concentrations of 5%, 25%, or 50% on three consecutive days, by an open application on the ears. Five vehicle control animals were similarly treated, but with vehicle alone(Propylene glycol). Three days after the last exposure, all animals were injected with 3H-methyl thymidine and after five hours the draining (auricular) lymph nodes were excised. After precipitating the DNA of the lymph node cells, radioactivity measurements were performed. The activity was expressed as the number of Disintegrations Per Minute (DPM) and a stimulation index was subsequently calculated for each group.

Mean DPM/animal values for the experimental groups treated with test substance concentrations 5, 25, and 50% were 1484, 9339 and 10539 respectively. The mean DPM/animals value for the vehicle control group was 195. The SI values calculated for the substance concentrations 5, 25, and 50% were 7.6, 48.0, and 54.2 respectively. The results show that the test substance elicited an SRI≥ 3.The data showed a dose-response and the EC3 value was established to be between 0 and 5%.


Migrated from Short description of key information:
A mouse LLNA study

Justification for selection of skin sensitisation endpoint:
Key study - full guideline, GLP study

Respiratory sensitisation

Endpoint conclusion
Endpoint conclusion:
no study available
Additional information:
Migrated from Short description of key information:
Currently no data are available to assess this endpoint.

Justification for classification or non-classification

Based on the positive finding in the LLNA study this substance meets the criteria for classification as a skin sensitiser.