1,4-naphthoquinone

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

secondary literature

Justification for type of information:

Study included as a supporting study to support Classification and Labelling and is not considered as reliable for REACH purposes as the full experimental report is not available. This method differs to the standard guinea pig maximisation tests and Buehler assay (although is most similar to the Buehler assay) in use at the time in terms of some aspects of the methodology, and little detail is available on the experimental conditions (animal numbers/status, guideline etc.). The induction doses used also appeared to cause corrosion based on the effects observed where standard tests require that this should only cause mild-irritation. The challenge dose should also cause no irritation rather than ‘minimal irritation’ which is not further specified.

Data source

Reference

Reference Type:

review article or handbook

Title:

1,4-Naphthoquinone - BUA Report 211 (October 1998)

Author:

GDCh-Advisory Committee on Existing Chemicals (BUA)

Year:

1998

Bibliographic source:

S.Hirzel Verlag Stuttgart; Wissenschaftliche Verlags-Gesellschaft Stuttgart, 2000 , ISBN3-7776-1064-X

Materials and methods

Test guideline

Qualifier:

no guideline followed

GLP compliance:

not specified

Type of study:

not specified

Justification for non-LLNA method:

Conducted test pre-dates the LLNA and in vitro/chemico skin sensitisation tests.

Test material

Test material information

Constituent 1

Reference substance name:

1,4-naphthoquinone

EC Number:

204-977-6

EC Name:

1,4-naphthoquinone

Cas Number:

130-15-4

Molecular formula:

C10H6O2

IUPAC Name:

1,4-naphthoquinone

Test material form:

solid

Specific details on test material used for the study:

No details on test substance purity

In vivo test system

Test animals

Species:

guinea pig

Strain:

not specified

Sex:

not specified

Study design: in vivo (non-LLNA)

No. of animals per dose:

Not specified

Details on study design:

The repeated painting of guinea pig skin over an 11-day period with 0.1, 0.5 and 1 % solutions of 1,4 -naphthoquinone in ether on days 1 to 2, 3 to 4 and 6 to 11, respectively, caused reddening of the skin at the beginning of the treatment with subsequent brown-black scab formation. After the local effects had healed up (by day 21) a 0.1 % solution (which had been shown to cause only minimal irritation after a single application) was applied on day 23 to part of the skin that had not previously been treated.

Positive control substance(s):

not specified

Results and discussion

Positive control results:

Not specified

In vivo (non-LLNA)

Results

Remarks on result:

positive indication of skin sensitisation

Any other information on results incl. tables

The repeat application of the 0.1% solution to the guinea pig skin after the local effects had abated (Day 23) led to local allergic reactions of the skin (reddening, oedema and nodule formation) in all of the animals, which diminished after 24 hours with mild peeling. Based on these effects the substance was considered to have the potential to be a skin sensitiser.

Applicant's summary and conclusion

Interpretation of results:

Category 1 (skin sensitising) based on GHS criteria

Conclusions:

The test substance assessed in a non-standard guinea pig painting study provided an indication that the substance would be a skin sensitiser although there were limitations in the methodology used as well as a lack of access to the source data.