4H-Pyrido[1,2-a]pyrimidin-4-one, 3-(2-chloroethyl)-9-hydroxy-2-methyl-, hydrochloride (1:1)

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

disregarded due to major methodological deficiencies

Study period:

2003-05-20 to 2003-06-10

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

significant methodological deficiencies

Remarks:

The study was conducted following SPL Standard Test method 595.12. However, very low doses were selected without justification. Study report was limited. Therefore a K score of 3 is assigned to this study.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2004

Report date:

2004

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

SPL Standard Test Method 595.12. : The assay determines the level of lymphocyte proliferation in lymph nodes draining the application site of
the test material. Determination of lymphocyte proliferation is quantified by measuring the incorporation of radiolabelled thymidine in the dividing lymph node cells. The proliferation response of lymph node cells was expressed as the number of radioactive disintegrations per minute per lymph node (dpm/node) and as the ratio of 3HTdR incorporation into lymph node cells of test nodes relative to that recorded for the control nodes (Stimulation Index).

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-CHLOROETHYL)-9-HYDROXY-2-METHYL-4H-PYRIDO[1,2-A]PYRIMIDIN-4-ONE HYDROCHLORIDE (1:1)

EC Number:

617-648-0

Cas Number:

849727-62-4

Molecular formula:

C11H11ClN2O2.HCl

IUPAC Name:

3-(2-CHLOROETHYL)-9-HYDROXY-2-METHYL-4H-PYRIDO[1,2-A]PYRIMIDIN-4-ONE HYDROCHLORIDE (1:1)

Test material form:

solid: particulate/powder

Specific details on test material used for the study:

- Name of test material (as cited in study report): HT 002006

In vivo test system

Test animals

Species:

mouse

Strain:

other: 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:

0.25%, 0.5% and 1% w/w

No. of animals per dose:

four/dose group

Details on study design:

RANGE FINDING TESTS:
- Compound solubility: no data
- Irritation: In a preliminary sighting test, no deaths or signs of systemic toxicity were observed at a concentration of 1%.
- Lymph node proliferation response: no data

MAIN STUDY
ANIMAL ASSIGNMENT AND TREATMENT
- Name of test method: LLNA, the test is designed to assess the skin sensitising potential (delayed-type hypersensitivity) of the test substance.
- Criteria used to consider a positive response: Test-to-control ratio greater than 3.0 indicated a positive result.


TREATMENT PREPARATION AND ADMINISTRATION:
- Three groups, each of four animals, were treated with 50 uL (25 uL per ear) of the test substance as a solution in dimethyl formamide at concentrations of 0.25%, 0.5%, and 1% v/v. A further group of four animals was treated with dimethyl formamide alone.

Positive control substance(s):

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

Statistics:

no data

Results and discussion

Positive control results:

see: any other information on results (here below)

In vivo (LLNA)

Results

Results 1

Parameter:

SI

Value:

1.84

Test group / Remarks:

0.25% w/w

Results 2

Parameter:

SI

Value:

1.39

Test group / Remarks:

5% w/w

Results 3

Parameter:

SI

Value:

2.55

Test group / Remarks:

1% w/w

Results 4

Parameter:

other: disintegrations per minute (DPM)

Remarks on result:

other: no data

Any other information on results incl. tables

Positive Control Local Lymph Node Assay in the Mouse (2003)

Start Date	Finish Date	Test Material	Concentration	Vehicle	Stimulation Index^a	Classification^b
13/03/2003	19/03/2003	α‑Hexylcinnamaldehyde, tech., 85%	5%, 10%, 25% v/v	acetone/olive oil 4:1	2.8, 2.3, 5.5	Positive
13/03/2003	19/03/2003	α‑Hexylcinnamaldehyde, tech., 85%	5%, 10%, 25% v/v	acetone/olive oil 4:1	2.0, 1.9, 6.8	Positive
10/10/2003	16/10/2003	α‑Hexylcinnamaldehyde, tech., 85%	5%, 10%, 25% v/v	acetone/olive oil 4:1	1.76, 2.78, 5.06	Positive
16/10/2003	22/10/2003	α‑Hexylcinnamaldehyde, tech., 85%	5%, 10%, 25% v/v	acetone/olive oil 4:1	1.49, 1.73, 5.26	Positive

a=        Ratio of test to control lymphocyte proliferation

b=        Stimulation index greater than 3.0 indicates a positive result

* =        Standard Test Method 595 (Pooled nodes)

·=        Standard Test Method 599 (Individual nodes)

Applicant's summary and conclusion

Interpretation of results:

study cannot be used for classification

Conclusions:

The test material was considered to be a non-sensitiser under the conditions of the test and should therefore not be classified.