Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

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:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2019

Materials and methods

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

Test material

Constituent 1
Chemical structure
Reference substance name:
ethyl (2S)-2-acetamido-3-[4-(4-methoxyphenoxy)-3,5-dinitrophenyl]propanoate
Cas Number:
83290-90-8
Molecular formula:
C20H21N3O9
IUPAC Name:
ethyl (2S)-2-acetamido-3-[4-(4-methoxyphenoxy)-3,5-dinitrophenyl]propanoate
Test material form:
solid

In vivo test system

Test animals

Species:
mouse
Strain:
CBA/Ca
Sex:
female
Details on test animals and environmental conditions:
The animals were housed in IVC polycarbonate cages (5 animals per cage) suspended on stainless steel racks, in a room equipped with central air-conditioning. The room temperature was within the range of 22 ± 3°C, relative humidity was at least of 30 % and did not exceed 70 %, the aim was 50-60 %. The light regimen was set to a 12-hour light / 12-hour dark cycle. The sanitation was performed according to standard operation procedures.

Study design: in vivo (LLNA)

Vehicle:
acetone/olive oil (4:1 v/v)
Concentration:
concentrations of 25 %, 50 % and 100 % w/v
No. of animals per dose:
Number of animals:
5 females – negative control (vehicle)
5 females – positive control
15 females – test item
4 females - pre-screen test, plus spare animals
Details on study design:
Day 1:
Each animal was identified and the body weight was recorded. To the dorsum of each ear 25 µL of the appropriate dilution of the test item, or the vehicle alone was applied.
Days 2 and 3:
The application procedure carried out on day 1 was repeated.
Days 4 and 5:
No treatment.
Day 6:
The body weight of each animal was recorded. 250 µL of sterile phosphate-buffered saline (PBS) containing 2 µCi (7.4 x 104 Bq) of 125I-iododeoxyuridine and 10-5M fluorodeoxyuridine was injected into all test and control mice via the tail vein.
Five hours later, the animals were sacrificed. The draining auricular lymph nodes from each ear were excised and pooled in PBS for each experimental group (pooled treatment group approach).
Positive control substance(s):
hexyl cinnamic aldehyde (CAS No 101-86-0)

Results and discussion

In vivo (LLNA)

Resultsopen allclose all
Key result
Parameter:
SI
Value:
0.91
Test group / Remarks:
25% group
Key result
Parameter:
SI
Value:
0.95
Test group / Remarks:
50% group
Key result
Parameter:
SI
Value:
1.44
Test group / Remarks:
100% group

Applicant's summary and conclusion

Interpretation of results:
GHS criteria not met
Conclusions:
The skin sensitization potential of L-Tyrosine, N-acetyl-O-(4-methoxyphenyl)-3,5-dinitro-, ethyl ester was evaluated by LLNA method, which basic underlying principle is that sensitizers induce a primary proliferation of lymphocytes in the auricular lymph nodes draining the site of chemical application.
In the present study, the test item was applied to the dorsum of each ear of five female mice (CBA/Ca) per group over three consecutive days, at three concentrations. All animals survived throughout the test period without showing any signs of local irritation. Two mice (No 1 and 2) treated with dose of 100 % of the test item showed signs of lethargy on day 2 and day 3 after treatment, and two mice (No 4 and 5) treated with the dose of 50 % of the test item showed signs of lethargy on day 3 after treatment.
Calculated SI values in treated groups remained under the value of 3, which is the threshold to consider the substance as a sensitizer. Therefore, it was not possible to calculate an EC3 value.
These results demonstrate that the test item L-Tyrosine, N-acetyl-O-(4-methoxyphenyl)-3,5-
dinitro-, ethyl ester was not a skin sensitizer under the test conditions of this study.