p-fluorophenyl 4-piperidyl ketone hydrochloride

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2004-02-02 to 2004-02-19

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Remarks:

Study is performed according to an internal method; however, the test substance is not adequately characterized and insufficient information is provided on the test animals, methodology and results.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2004

Report date:

2004

Materials and methods

Test guideline

Test guideline 1

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 results. There was no positive control substance used in the study; positive control data from the CRO included in section Any other information on results

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: SPL Standard Test method 595.12

Principles of method if other than guideline:

The study is performed according to SPL Standard Test Method 595.12.

GLP compliance:

no

Remarks:

This study was conducted in a facility operating to Good Laboratory Practice within the UK national GLP monitoring programme, but 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:

p-fluorophenyl 4-piperidyl ketone hydrochloride

EC Number:

247-070-0

EC Name:

p-fluorophenyl 4-piperidyl ketone hydrochloride

Cas Number:

25519-78-2

Molecular formula:

C12H14FNO.ClH

IUPAC Name:

4-(4-fluorobenzoyl)piperidine hydrochloride

Test material form:

solid: particulate/powder

Specific details on test material used for the study:

- Name of test material (as cited in study report): T 1047
- Substance type: no data
- Physical state: no data
- Analytical purity: no data
- Purity test date: no data
- Lot/batch No.: no data
- Expiration date of the lot/batch: no data
- Stability under test conditions: no data
- Storage condition of test material: no data
- Other: no data

In vivo test system

Test animals

Species:

mouse

Strain:

other: CBA/Ca

Sex:

not specified

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: no data
- Age at study initiation: no data
- Weight at study initiation: no data
- Housing: no data
- Diet (e.g. ad libitum): no data
- Water (e.g. ad libitum): no data
- Acclimation period: no data


ENVIRONMENTAL CONDITIONS
- Temperature (deg C): no data
- Humidity (%): no data
- Air changes (per hr): not applicable
- Photoperiod (hrs dark / hrs light): no data


IN-LIFE DATES: From: no data To: no data

Study design: in vivo (LLNA)

Vehicle:

dimethyl sulphoxide

Concentration:

5%, 10% or 25% w/w in dimethyl sulphoxide

No. of animals per dose:

three groups, each of four animals

Details on study design:

RANGE FINDING TESTS:
- Compound solubility: no data
- Irritation: no data
- Lymph node proliferation response: no data
- There were no signs of systemic toxicity following a preliminary sighting test at a concentration of 25% w/w.

MAIN STUDY
ANIMAL ASSIGNMENT AND TREATMENT
- Name of test method: SPL Standard Test Method 595.12
- Criteria used to consider a positive response: Test to control ratio greater than 3.0 indicates a 'positive' result.

TREATMENT PREPARATION AND ADMINISTRATION:
Three groups of four animals were treated with 50 uL of the test material (25 uL per ear) as a solution in dimethyl sulphoxide at concentrations of 5%, 10% or 25% w/w. A further group of four animals was treated with dimethyl sulphoxide alone.

Positive control substance(s):

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

other: 2,4-Dinitrobenzenesulfonic acid, sodium salt in 1% pluronic F-68 in distilled water

Statistics:

no data

Results and discussion

Positive control results:

See section Any other information on results incl. tables

In vivo (LLNA)

Results

Results 1

Parameter:

SI

Value:

3.72

Test group / Remarks:

5%

Results 2

Parameter:

SI

Value:

6.92

Test group / Remarks:

10%

Results 3

Parameter:

SI

Value:

8.23

Test group / Remarks:

25%

Any other information on results incl. tables

Positive Control Local Lymph Node Assay in the Mouse (2004)

Project Number	Start Date	Finish Date	Test Material	Concentration	Vehicle	Stimulation Index^a	Classification^b
039/687·	29/04/2004	05/05/2004	α‑Hexylcinnamaldehyde, tech., 85%	5%, 10%, 25% v/v	acetone/olive oil 4:1	1.40, 2.23, 6.09	Positive
039/688*	29/04/2004	05/05/2004	α‑Hexylcinnamaldehyde, tech., 85%	5%, 10%, 25% v/v	acetone/olive oil 4:1	1.74, 2.20, 8.89	Positive
039/719*	14/10/2004	26/10/2004	α‑Hexylcinnamaldehyde, tech., 85%	5%, 10%, 25% v/v	tetrahydrofuran	1.97, 3.71, 7.82	Positive
039/720*	29/09/2004	05/10/2004	2,4‑Dinitrobenzenesulfonic acid, sodium salt	1%, 10%, 20% v/v	1% pluronic F-68 in distilled water	1.03, 4.41, 13.55	Positive
039/723*	27/10/2004	02/11/2004	α‑Hexylcinnamaldehyde, tech., 85%	10%, 25%, 50% v/v	cottonseed oil	1.52, 2.63, 5.07	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)

 

 

EC3 CALCULATION: no EC3 value could be calculated based on the classical linear method as the SI values at all concentrations were > 3
Ryan et al. (2007)* described a method for calculation of an extrapolated EC3 value based on following formula:
EC3ex = 2^{log2(c) + (3-d)/(b-d) x [log2(a)-log2(c)]}
Based on the results of this LLNA study the results are the following:
EC3ex = 4.28
with a=10, b=6.92, c=5, d=3.72

As described by Ryan et al., two aspects of data quality can affect the accuracy of potency classification of the datapoints used: the slope ratio and the value of the lowest SI obtained and the closest above 3%.
- The dose response curve location of the extrapolation datapoints was determined by calculating a ratio of the slopes between the second and third and the first and second points. A higher degree of accuracy was found in the extrapolated values derived from curves with slope ratios below 2, indicating that the use of points which lie on the linear portion of the dose response curve results in more reliable potency class estimations. A significant correlation was also found between the lowest SI value and the accuracy of EC3 values derived by the log-linear extrapolation. For this substance the slope ratio was calculated to be 0.14.
- The reliability of the extrapolated values was found to be greater when the lower SI value used in the calculation approached 3 which is the case for this substance.
Of these two parameters, it appears that the slope ratio is more important to consider.
Both conditions related to data quality have been met for this substance which means the potency calculation is considered accurate.

* Ryan CA, Chaney JG, Gerberick GF, Kern, PS, Dearman RJ, Kimber I and Basketter DA. Extrapolating Local Lymph Node Assay EC3 Values To Estimate Relative Sensitizing Potency. Cutaneous and Ocular Toxicology (2007); 26(2): 135-145.

Applicant's summary and conclusion

Interpretation of results:

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

Conclusions:

The test item was considered to be a skin sensitiser category 1B based on the extraoplated EC3 value of 4.28% as established using the data of this LLNA study and the method described by Ryan et al., 2007.