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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
Study period:
2008-02-05 to 2008-03-04
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: well performed study in compliance with elementary guideline requirements

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2008
Report date:
2008

Materials and methods

Test guideline
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)
Version / remarks:
adopted 24 April 2002
Deviations:
yes
Remarks:
only the highest test item concentration, which can be technically used, was tested
Principles of method if other than guideline:
Only the highest test item concentration, which can be technically used, was tested.
GLP compliance:
yes
Remarks:
Only for the positive control
Type of study:
mouse local lymph node assay (LLNA)

Test material

Constituent 1
Chemical structure
Reference substance name:
1,3-dihydro-5-nitro-2H-benzimidazol-2-one
EC Number:
202-282-2
EC Name:
1,3-dihydro-5-nitro-2H-benzimidazol-2-one
Cas Number:
93-84-5
Molecular formula:
C7H5N3O3
IUPAC Name:
5-nitro-1,3-dihydro-2H-benzimidazol-2-one

In vivo test system

Test animals

Species:
mouse
Strain:
other: CBA/CaOlaHsd
Sex:
female
Details on test animals and environmental conditions:
- Age 8-9 weeks
- Single caging
- Acclimatisation: At least 5 days prior to the start of dosing unter test conditions after health examination
- Tap water, ad libitum
- Temperature: 22 +/- 3 °C
- Humidity: 30-70%
- Artificial light: 6a.m. - 6 p.m.

Study design: in vivo (LLNA)

Vehicle:
dimethyl sulphoxide
Concentration:
25 %
No. of animals per dose:
4
Details on study design:
RANGE FINDING TESTS:
- Compound solubility: The highest test item concentration, which can be technically used was a 25 % solution in dimethylsulfoxide.
- Irritation: no irritation at concentrations of 3.13, 6.25, 12.5, and 25 %

MAIN STUDY
ANIMAL ASSIGNMENT AND TREATMENT
- Name of test method: Local Lymph Node Assay (LLNA) in Mice
- Criteria used to consider a positive response: if exposure to at least one concentration of the test item resulted in an incorporation of 3HTdR at least 3-fold or greater than that recorded in control mice,


TREATMENT PREPARATION AND ADMINISTRATION: Each test group of mice was treated by topical (epidermal) application to the dorsal surface of each ear lobe (left and right) with one test item concentration of 25% (w/v) in dimethylsulfoxide. A further group of mice was treated with an equivalent volume of the relevant vehicle alone (control animals).
Positive control substance(s):
hexyl cinnamic aldehyde (CAS No 101-86-0)

Results and discussion

Positive control results:
S.I. of alpha-Hexylcinnamaldehyde
5%: 1.78
10%: 1.84
25%: 4.87

In vivo (LLNA)

Resultsopen allclose all
Parameter:
SI
Remarks on result:
other: 0% (w/v) 25% (w/v) 1.93 SI
Parameter:
other: disintegrations per minute (DPM)
Remarks on result:
other: 0% (w/v) 7134 DPM 25% (w/v) 13775 DPM

Applicant's summary and conclusion

Interpretation of results:
not sensitising
Remarks:
Migrated information
Conclusions:
The test item Nitrolon was not a skin sensitizer under the described conditions
Executive summary:

In the study the test item 5 -Nitrobenzimidazolon TF dissolved in dimethylsulfoxide (dmso) was assessed for its possible contact allergenic potential.

For this purpose a Local Lymph Node Assay was performed using a test item concentration of 25%.

The animals did not show any clinical signs during the course of the study and no cases of mortality were observed.

In this study a stimulation index (S.I.) of 1.93 was determined with the test item at a concentration of 25% in dmso.

The test item 5-Nitrobenzimidazolon TF was NOT A SKIN SENSITISER.