(S)-2-methyl-5-(1-methylvinyl)cyclohex-2-en-1-one

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Justification for type of information:

Data is from peer reviewed journal

Data source

Reference

Reference Type:

publication

Title:

Correlation between experimental human and murine skin sensitization induction thresholds

Author:

Anne Marie Api, David Basketter, and Jon Lalko

Year:

2015

Bibliographic source:

Cutaneous and ocular toxicology, 34, no. 4, (2015), 298-302.

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Principles of method if other than guideline:

To evaluate the skin sensitization potential of D-Carvone by Mouse Local Lymph Node Assay.

GLP compliance:

not specified

Type of study:

mouse local lymph node assay (LLNA)

Test material

Test material information

Constituent 1

Reference substance name:

(5S)-2-methyl-5-(prop-1-en-2-yl)cyclohex-2-en-1-one

Cas Number:

2244-16-8

Molecular formula:

C10H14O

IUPAC Name:

(5S)-2-methyl-5-(prop-1-en-2-yl)cyclohex-2-en-1-one

Test material form:

liquid

Details on test material:

- Name of test material: d-Carvone- IUPAC name: (5S)-2-methyl-5-(prop-1-en-2-yl)cyclohex-2-en-1-one- Molecular formula: C10H14O- Molecular Weight: 150.22 g/mole- Smiles Notation: C1[C@H](CC=C(C1=O)C)C(C)=C- Inchl: 1S/C10H14O/c1-7(2)9-5-4-8(3)10(11)6-9/h4,9H,1,5-6H2,2-3H3/t9-/m0/s1- Substance type: Organic- Physical state: Colorless to pale-yellow liquid

Specific details on test material used for the study:

- Name of test material: d-Carvone- IUPAC name: (5S)-2-methyl-5-(prop-1-en-2-yl)cyclohex-2-en-1-one- Molecular formula: C10H14O- Molecular Weight: 150.22 g/mole- Smiles Notation: C1[C@H](CC=C(C1=O)C)C(C)=C- Inchl: 1S/C10H14O/c1-7(2)9-5-4-8(3)10(11)6-9/h4,9H,1,5-6H2,2-3H3/t9-/m0/s1- Substance type: Organic- Physical state: Colorless to pale-yellow liquid

In vivo test system

Test animals

Species:

mouse

Strain:

CBA/Ca

Sex:

female

Details on test animals and environmental conditions:

No data availlable

Study design: in vivo (LLNA)

Vehicle:

other: 1:3 ethanol :diethyl phthalate.

Concentration:

25 µl (Each group received one of five test concentrations prepared as a w/v%.)

No. of animals per dose:

Total=5

Details on study design:

MAIN STUDYANIMAL ASSIGNMENT AND TREATMENT- Name of test method: LLNA- Criteria used to consider a positive response: EC 3 value TREATMENT PREPARATION AND ADMINISTRATION: Groups of female CBA/CA mice were dosed topically on the dorsum of each ear with 25 µl of test fragrance in 1:3 ethanol: diethyl phthalate.Each group received one of five test concentrations preparedas a w/v%.

Positive control substance(s):

other:

Results and discussion

In vivo (LLNA)

Results

Key result

Parameter:

SI

Value:

2 650

Variability:

not specified

Test group / Remarks:

5 mice

Remarks on result:

other: Sensitizing to skin

Cellular proliferation data / Observations:

CELLULAR PROLIFERATION DATA: Suspensions of the lymph node cells were prepared by mechanical disaggregation through 200- mesh stainless steel gauze. The cell suspensions were washedthree times with phosphate buffered saline and precipitated overnight at 4°C with 5% w/v trichloroacetic acid (TCA). Thesamples were then pelleted by centrifugation. The cells wereresuspended in 1ml of TCA and transferred to scintillation vials containing 10 ml of scintillation fluid. The incorporationof 3HTdR was measured by b-scintillation counting and expressed as disintegrations per minute (dpm) per lymph node for each experimental group.DETAILS ON STIMULATION INDEX CALCULATION : The stimulation index (SI)values were calculated for each dose level. A SI of 3 or more was considered to give a positive response.EC3 CALCULATION : The EC3 valuewas taken as a measure of relative potency

Applicant's summary and conclusion

Interpretation of results:

Category 1 (skin sensitising) based on GHS criteria

Conclusions:

The EC3 value obtained from LLNA assay performed to assess the sensitizing potential of d-Carvone was 2650 microgram/sq cm. Based on this value, d-Carvone can be considered to be sensitizing to skin.

Executive summary:

Skin sensitization potential of d-Carvone was evaluated by Local Lymph Node Assay (LLNA) The LLNAs were conducted according to the method described in OECD Guideline 429. Groups of female CBA/CA mice (n= 5) were dosed topically on the dorsum of each ear with 25 ml of test material in 1:3 ethanol :diethyl phthalate. Each group received one of five test concentrations prepared as a w/v%. A concurrent vehicle control group was similarly treated with 1:3 ethanol: diethyl phthalate.

Dosing occurred daily for three consecutive days. The animals received no treatment for two days and on the sixth day after the first application, all mice were injected intravenously via the tail vein with 250 ml of phosphate buffered saline containing 20 µCi of radiolabelled methyl thymidine (3HTdR). Five hours later, the mice were euthanized and the draining auricular lymph nodes were excised and pooled . Suspensions of the lymph node cells were prepared by mechanical disaggregation through 200-mesh stainless steel gauze. The cell suspensions were washed three times with phosphate buffered saline and precipitated overnight at 4 °C with 5% w/v trichloroacetic acid (TCA). The samples were then pelleted by centrifugation. The cells were resuspended in 1ml of TCA and transferred to scintillation vials containing 10 ml of scintillation fluid. The incorporation of 3HTdR was measured by β- scintillationcounting and expressed as disintegrations per minute (dpm) per lymph node.

The EC3 value obtained from LLNA assay performed to assess the sensitizing potential of d-Carvone was 2650 microgram/sq cm. Based on this value, d-Carvone can be considered to be sensitizing to skin.