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Toxicological information

Skin sensitisation

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Administrative data

Endpoint:
skin sensitisation: in vivo (LLNA)
Type of information:
experimental study
Adequacy of study:
key study
Study period:
From 26 January, 2017 to 21 February, 2017
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2017
Report Date:
2017

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

In vivo test system

Test animals

Species:
mouse
Strain:
CBA:J
Sex:
female

Study design: in vivo (LLNA)

Vehicle:
other: Ethanol/diethylphthalate (1:3 v/v)
Concentration:
25, 50 or 100% w/w
No. of animals per dose:
five
Details on study design:
In the main study, three experimantal groups of five female CBA/J mice were treated with test item concentrations of 25, 50 or 100% w/w on three consecutive days, by open application on the ears. Five vehicle control animals were similarly treated, but with the vehicle alone (Ethanol/diethylphthalate (1:3 v/v)) and another group of five animals received a positive control item (HCA).
Three days after the last exposure, all animals were injected with 3H-methyl thymidine and after hours the draining (auricular) lymph nodes were excised and pooled for each animal. 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 (SI) was subsequently calculated for each group.
Positive control substance(s):
hexyl cinnamic aldehyde (CAS No 101-86-0)
Statistics:
no

Results and discussion

Positive control results:
The SI value calculated for the positive control group was 3.6.

In vivo (LLNA)

Resultsopen allclose all
Key result
Parameter:
SI
Value:
0.9
Test group / Remarks:
25% test item concentration
Key result
Parameter:
SI
Value:
1.2
Test group / Remarks:
50% test item concentration
Key result
Parameter:
SI
Value:
1.9
Test group / Remarks:
100% test item concentration
Cellular proliferation data / Observations:
Very slight erythema was noted for several animals treated at 50% and all animals treated at 100% and the positive control item between Days 1 and 3, which was considered not to have a toxicologically significant effect on the activity of the nodes.
The majority of auricular lymph nodes were considered normal in size, except for all nodes in the animals treated with the positive control, which were considered enlarged. No macroscopic abnormalities of the surrounding area were noted for any of the animals.
Mean DPM/animal values for the experimental groups treated with test item concentrations 25, 50 and 100% were 559, 745 and 1140 DPM, respectively. The mean DPM/animal value for the vehicle control group was 601 DPM and a mean DPM/animal value of 2159 DPM was obtained from the positive control group. The SI values calculated for the test item concentrations 25, 50 and 100% were 0.9, 1.2 and 1.9, respectively. The SI value calculated for the positive control group was 3.6.
Since there was no indication that the test item elicited a SI >=3 when tested up to 100%, KURIMATE was not considered to be a skin sensitizer.

Applicant's summary and conclusion

Interpretation of results:
GHS criteria not met
Conclusions:
KURIMATE was not considered to be a skin sensitizer.