2,2'-(1,4-phenylene)bis[4-[(4-methoxyphenyl)methylene]oxazol-5(4H)-one]

Endpoint summary

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2007

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Current guidelin, GLP

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes

Type of study:

mouse local lymph node assay (LLNA)

Species:

mouse

Strain:

CBA

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Harlan Netherlands B.V. Postbus 6174 NL - 5960 AD Horst / The Netherlands
- Age at study initiation: 7 - 8 weeks (beginning of acclimatisation)
- Weight at study initiation: no data
- Housing: Makrolon Type I, with wire mesh top (EHRET GmbH, D-79302 Emmendingen)
- Diet (e.g. ad libitum): pelleted standard diet, ad libitum
- Water (e.g. ad libitum): tap water, ad libitum,


ENVIRONMENTAL CONDITIONS
temperature 22 + 3°C
relative humidity 30-74%
artificial light 6.00 a.m. - 6.00 p.m.

Vehicle:

acetone/olive oil (4:1 v/v)

Concentration:

6.25, 12.5, and 25% (w/v) in acetone:olive oil (4+1).

No. of animals per dose:

4

Positive control substance(s):

not specified

Parameter:

other: disintegrations per minute (DPM)

Remarks on result:

other: see table below

see table below

Interpretation of results:

not sensitising

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The test item was found to be not a skin sensitiser under the
described conditions.

Executive summary:

In order to study a possible contact allergenic potential of the test item, three groups each of four female mice were treated daily with the test item at concentrations of 6.25, 12.5, and 25% (w/v) in acetone:olive oil (4+1) by topical application to the dorsum of each ear lobe (left and right) for three consecutive days.

A control group of four mice was treated with the vehicle (acetone:olive oil (4+1)) only.

Five days after the first topical application the mice were injected intravenously into a tail vein with radio-labelled thymidine (3H-methyl thymidine). Approximately five hours after intravenous injection, the mice were sacrificed, the draining auricular lymph nodes excised and pooled per group. Single cell suspensions of lymph node cells were prepared from pooled lymph nodes, which were subsequently washed and incubated with trichloroacetic acid overnight. The proliferative capacity of pooled lymph node cells was determined by the incorporation of 3H-methyl thymidine measured in a ß-scintillation counter.

All treated animals survived the scheduled study period and no signs of toxicity were observed.

A test item is regarded as a sensitiser in the LLNA if the exposure to one or more test concentration resulted in 3-fold or greater increase in incorporation of 3HTdR compared with concurrent controls, as indicated by the Stimulation Index (S.I.). The estimated concentration of test item required to produce a S.I. of 3 is referred to as the EC3 value.

In this study Stimulation Indices (S.I.) of 2.1, 1.8, and 0.7 were determined with the test item at concentrations of 6.25, 12.5, and 25% in acetone:olive oil (4+1), respectively. The EC3 value could not be calculated, since none of the tested concentrations induced an S.I. greater than 3.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

The test item did noch increase the stimulation index (SI) above 3 in a mouse local lymph node assa. The material is not considered a skin sensitiser.

Migrated from Short description of key information:
The test item did not increase the stimulation index (SI) above 3 in a mouse local lymph node assay.

Justification for selection of skin sensitisation endpoint:
only availible study

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

no classification

The test item did not increase the stimulation index (SI) above 3 in a mouse local lymph node assay.