TRACER YELLOW D-100

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: According to OECD guideline 429 and EC test method B42

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.42 (Skin Sensitisation: Local Lymph Node Assay)

GLP compliance:

yes (incl. QA statement)

Remarks:

Harlan cytotest cell research GmbH

Type of study:

mouse local lymph node assay (LLNA)

Test material

Test material information

Constituent 1

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

orange solid powder

In vivo test system

Test animals

Species:

mouse

Strain:

CBA

Sex:

female

Study design: in vivo (LLNA)

Vehicle:

dimethylformamide

Concentration:

25µl/ear/day

No. of animals per dose:

16

Results and discussion

In vivo (LLNA)

Results

Parameter:

SI

Remarks on result:

other: S.I. 1.26, 1.43 and 2.11 at concentrations of 2.5, 5 and 10% (w/w) in dimethylformamide.

Applicant's summary and conclusion

Interpretation of results:

not sensitising

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

D-100 is not a skin sensitiser

Executive summary:

In order to study a possible skin sensitising potential of D-100, three groups each of four female mice were treated with the test item at concentrations of 2.5, 5 and 10% (w/w) in dimethylformamide by topical application to the dorsum of each ear for three consecutive days. The highest concentration tested was the highest concentration that could be achieved whilst avoiding systemic toxicity and excessive local skin irritation as confirmed by two pre-experiments. A control group of four mice was treated with the vehicle (dimethylformamide) only. Five days after the first topical application the mice were injected intravenously into a tail vein with radio-labelled thymidine (H-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 H-methyl thymidine measured in a B-scintillation counter.

All treated animals survived the scheduled study period and no signs of systemic toxicity or local skin irritation were observed.

A test item is regarded as a sensitiser in the LLNA if the exposure to one or more test concentration resulted in a 3-fold or greater increase in incorporation of HTdR 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 of 1.26, 1.43 and 2.11 were determined with the test item at concentrations of 2.5, 5, and 10 %(w/w) in dimethylformamide. A clear dose response was observed. The EC3 value could not be calculated, since none of the tested concentrations induced a S.I. greater than the threshold value of 3.

The test item D-100 was not a skin sensitiser under the test conditions of this study.