Reaction mass of 2-[(4-methyl-2-nitrophenyl)diazenyl]-3-oxo-N-phenylbutanamide and 2-[(4-nitrophenyl)diazenyl]-3-oxo-N-phenylbutanamide

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

other: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Structure similarity.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2005

Report date:

2005

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

Test material information

Constituent 1

Reference substance name:

2-[(4-methyl-2-nitrophenyl)azo]-3-oxo-N-phenylbutyramide

EC Number:

219-730-8

EC Name:

2-[(4-methyl-2-nitrophenyl)azo]-3-oxo-N-phenylbutyramide

Cas Number:

2512-29-0

Molecular formula:

C17H16N4O4

IUPAC Name:

2-[(4-methyl-2-nitrophenyl)diazenyl]-3-oxo-N-phenylbutanamide

Test material form:

solid: particulate/powder

In vivo test system

Test animals

Species:

mouse

Strain:

CBA

Sex:

female

Study design: in vivo (LLNA)

Vehicle:

dimethyl sulphoxide

Concentration:

0%, 2%, 4%, 8% (w/v)

No. of animals per dose:

5 females per dose group2 females in the pre-test

Details on study design:

RANGE FINDING TESTS: - non GLP- Compound solubility: 8% (w/v) suspension in DMSO was the highest technically applicable concentration; higher concentrations could also not be achieved with other vehicles- Irritation: no swelling was observed at concentrations of 1.0, 2.0, 4.0 and 8.0% (w/v) after a single application- Systemic toxicity: not observed up to the highest concentration tested- Lymph node proliferation response: not examinedMAIN STUDYANIMAL ASSIGNMENT AND TREATMENT- Name of test method: LLNA- Criteria used to consider a positive response:1: exposure to at least one concentration of the test item resulted in an incorporation of 3H-methyl thymidine at least 3-fold or greater than that recorded in control mice as indicated by the stimulation index2: data are compatible with a conventional dose response, although allowance must be made for either local toxicity or immunological suppressionTREATMENT PREPARATION AND ADMINISTRATION:- individual preparation of weight volume dilutions using a magnetic stirrer as homogenizer- test item preparations were made freshly before each dosing occasion- 25 µl were spread over the entire dorsal surface of each ear lobe once daily for three consecutive days

Positive control substance(s):

hexyl cinnamic aldehyde (CAS No 101-86-0)

Statistics:

- calculation of mean values and standard deviations for body weight- Dunnett-test (ANOVA) to test for statistical significance of the results between the test item groups

Results and discussion

In vivo (LLNA)

Results

Key result

Parameter:

SI

Value:

> 1 - < 1.4

Remarks on result:

other: Stimulation indices were all below 3. The following SI were calculated: 2% test item: 1.3 4% test item: 1.2 8% test item: 1.4

Any other information on results incl. tables

The animals did not show any clinical signs during the course of the study and no cases of mortality were observed. The body weight of the animals was within the normal range. Calculation of the EC3 value was not performed, because no test concentration produced a SI of 3 or higher.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The test substance was not sensitising in this LLNA in concentrations up to 8% (w/v) in DMSO, the highest technically achievable concentration.

Executive summary:

The test item was assessed for its possible contact allergenic potential in a local lymph node assay according to OECD TG 429. The test was performed using test item concentrations of 2, 4 and 8% (w/v). The animals (5 female mice/dose group) did not show any clinical signs during the course of the study and no cases of mortality were observed. In this study Stimulation Indices (S.I.) of 1.3, 1.2 and 1.4 were determined with the test item at concentrations of 2, 4 and 8% (w/v) in DMSO, respectively. The results obtained with the positive control confirmed the validity of the test. The test item was not a skin sensitiser under the conditions tested.