4H-Pyrido[1,2-a]pyrimidin-4-one, 3-[2-[4-[(Z)-(2,4-difluorophenyl)(hydroxyimino)methyl]-1-piperidinyl]ethyl]-6,7,8,9-tetrahydro-2-methyl-

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2004-01-27 to 2004-02-10

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Data source

Reference

Reference 1

Reference Type:

study report

Title:

Unnamed

Year:

2004

Report date:

2004

Reference 2

Reference Type:

other: expert report

Title:

Unnamed

Year:

2015

Report date:

2015

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

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

Deviations:

yes

Remarks:

Insufficient information on the test substance, test animals, methodological details and information on results presented.

GLP compliance:

no

Remarks:

The study was conducted in a facility operating to Good Laboratory Practice within the UK national GLP monitoring programme, but the study report has not been audited by the QA unit. No formal claim of GLP compliance is made for this study.

Type of study:

mouse local lymph node assay (LLNA)

Test material

Test material information

Constituent 1

Reference substance name:

3-(2-{4-[(Z)-(2,4-DIFLUOROPHENYL)(HYDROXYIMINO)METHYL]PIPERIDIN-1-YL}ETHYL)-2-METHYL-6,7,8,9-TETRAHYDRO-4H-PYRIDO[1,2-A]PYRIMIDIN-4-ONE

EC Number:

603-689-1

Cas Number:

132961-05-8

Molecular formula:

C23H28F2N4O2

IUPAC Name:

3-(2-{4-[(Z)-(2,4-DIFLUOROPHENYL)(HYDROXYIMINO)METHYL]PIPERIDIN-1-YL}ETHYL)-2-METHYL-6,7,8,9-TETRAHYDRO-4H-PYRIDO[1,2-A]PYRIMIDIN-4-ONE

Test material form:

solid: particulate/powder

Specific details on test material used for the study:

No data

In vivo test system

Test animals

Species:

mouse

Strain:

CBA/Ca

Sex:

not specified

Details on test animals and environmental conditions:

TEST ANIMALS: no data

ENVIRONMENTAL CONDITIONS: no data


IN-LIFE DATES: no data

Study design: in vivo (LLNA)

Vehicle:

dimethylformamide

Concentration:

concentrations of 1%, 2.5% or 5% w/w.

No. of animals per dose:

4 females per group, 3 groups

Details on study design:

RANGE FINDING TESTS:
- Compound solubility: no data
- Irritation: no data
- Lymph node proliferation response: no data
- Other: In a preliminary sighting test, there were no signs of systemic toxicity at a concentration of 5% w/w in dimethyl formamide.


MAIN STUDY
ANIMAL ASSIGNMENT AND TREATMENT
- Name of test method: 3HTdR incorporation
- Criteria used to consider a positive response: Test to control ratio for stimulation index greater than 3.0 indicates a 'positive' result


TREATMENT PREPARATION AND ADMINISTRATION:
- The test animals were treated with 50 µL of the test substance (25 µL per ear).

Positive control substance(s):

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

other: 2,4 Dinitrobenzenesulfonic acid, sodium salt at 1%, 10%, 20% v/v in 1% pluronic F-68 in distilled water

Statistics:

no data

Results and discussion

Positive control results:

see: any overall remarks, attachments below

In vivo (LLNA)

Results

Results 1

Parameter:

SI

Value:

1.15

Test group / Remarks:

1 % w/w group

Results 2

Parameter:

SI

Value:

1.66

Test group / Remarks:

2.5% w/w group

Results 3

Parameter:

SI

Value:

2.58

Test group / Remarks:

5 % w/w group

Any other information on results incl. tables

A Stimulation Index greater than 3.0 indicates a positive result.

Applicant's summary and conclusion

Interpretation of results:

Category 1B (indication of skin sensitising potential) based on GHS criteria

Conclusions:

Study conclusion: the test material was considered to be a non-sensitiser under the conditions of the test.

Expert conclusion: in this LLNA the possible contact allergenic potential of the test item T1624 was assessed using test concentrations of 1, 2.5 and 5%. It is not clear from the study report if 5% was the highest possible concentration. The stimulation indices at these concentrations were 1.15, 1.66 and 2.58 respectively.
Due to the fact that the S.I. at the highest tested concentration was just below 3, it was decided to classify this compound as a mild skin sensitizer for occupational health perspectives.
Therefore, the substance is considered to be classified as skin sensitising category 1B, according to CLP Regulation.