N,N'-diacetylhydrazine

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

2004-03-08 to 2004-03-23 (experimental phase)

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

The study is a screening study which did not formally follow a guideline method, and was not formally performed under audited GLP, however, the laboratory facilities were operated according to GLP. The purity of the test material was not reported. The documentation in the report was very limited. Although the results are considered valid, the screening study itself cannot be considered formally reliable due to the lack of formal guideline, quality assurance, and very limited documentation.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2004

Report date:

2004

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)

Deviations:

no

Remarks:

relevant deviations from SOP specifications were not reported

Principles of method if other than guideline:

The study was performed according to the internal standard operational procedure 595.12 of the laboratory, but no details on this SOP are given in the report. The principles of the internal SOP are to the greatest extent similar to those described in OECD Testing Guideline No. 429 (Mouse Local Lymph Node Assay).

GLP compliance:

no

Type of study:

mouse local lymph node assay (LLNA)

Test material

Test material information

Constituent 1

Reference substance name:

N,N'-diacetylhydrazine

EC Number:

221-576-1

EC Name:

N,N'-diacetylhydrazine

Cas Number:

3148-73-0

Molecular formula:

C4H8N2O2

IUPAC Name:

N'-acetylacetohydrazide

Test material form:

not specified

In vivo test system

Test animals

Species:

mouse

Strain:

other: CBA/Ca

Sex:

not specified

Details on test animals and environmental conditions:

not reported

Study design: in vivo (LLNA)

Vehicle:

dimethyl sulphoxide

Concentration:

2.5, 5 and 10% w/w

No. of animals per dose:

four animals

Details on study design:

RANGE FINDING TESTS:
- Compound solubility: not reported
- Irritation: not reported
- Lymph node proliferation response: not reported
- Other responses: clinical observations, body weight change, mortality

MAIN STUDY
- Criteria used to consider a positive response: stimulation index
- Vehicle control: four animals treated with dimethyl sulphoxide

TREATMENT PREPARATION AND ADMINISTRATION:
- Vehicle: dimethyl sulphoxide
- Application/site: topical on the dorsal surface of ears
- Application volumes: 25 µL per ear

Statistics:

not reported

Results and discussion

Positive control results:

no positive control tested

In vivo (LLNA)

Results

Results 1

Parameter:

SI

Remarks on result:

other: Vehicle: not applicable 2.5% w/w in dimethyl sulphoxide: 1.01 5% w/w in dimethyl sulphoxide: 1.43 10% w/w in dimethyl sulphoxide: 0.78

Results 2

Parameter:

other: disintegrations per minute (DPM)

Remarks on result:

other: Vehicle: 7571.75 DPM, 946.47 DPM/Node 2.5% w/w in dimethyl sulphoxide: 7665.04 DPM, 958.13 DPM/Node 5% w/w in dimethyl sulphoxide: 10815.94 DPM, 1351.99 DPM/Node 10% w/w in dimethyl sulphoxide: 5933.59 DPM, 741.70 DPM/Node

Any other information on results incl. tables

No signs of systemic toxicity or body weight changes and no mortality were observed in the screening test applying a solution of the test substance in dimethyl sulphoxide at a concentration of 10% w/w to the skin surface of the ears.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The test substance was considered as a non-sensitiser under the conditions of the Mouse Local Lymph Node Assay. Although the result is considered to be valid, due to the lack of formal guideline and quality assurance, and very limited documentation, it must be regarded as not being reliable.

Executive summary:

The potential for skin sensitisation of the test substance was investigated in a non-GLP mouse local lymph node assay in CBA/Ca mice that was conducted according to principles similar to those given in OECD Testing Guideline No. 429. Following a preliminary sighting test at which there were no deaths or signs of systemic toxicity at a concentration of 10% w/w, three groups, each of four animals, were treated with 50 µL of the test material (25 µL per ear) as a solution in dimethyl sulphoxide at concentrations of 2.5%, 5% and 10% w/w. A further group of four animals was treated with dimethyl sulphoxide alone. The Stimulation Indeces expressed as the mean radioactive incorporation for each treatment group divided by the mean radioactive incorporation of the vehicle group were 1.01, 1.43 and 0.78 for the groups treated with concentrations of 2.5, 5 and 10% w/w, respectively and hence below the threshold of 3.0 indicating a positive result.