Reactionmass of dodecan-2-yl prop-2-enoate and dodecan-3-yl prop-2-enoate and dodecan-4-yl prop-2-enoate

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2016

Report date:

2016

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

2010

Deviations:

no

GLP compliance:

yes

Type of study:

mouse local lymph node assay (LLNA)

Test material

Test material information

Constituent 1

Reference substance name:

Reactionmass of dodecan-2-yl prop-2-enoate and dodecan-3-yl prop-2-enoate and dodecan-4-yl prop-2-enoate

EC Number:

947-818-2

Cas Number:

1612783-92-2

Molecular formula:

C15H28O2

IUPAC Name:

Reactionmass of dodecan-2-yl prop-2-enoate and dodecan-3-yl prop-2-enoate and dodecan-4-yl prop-2-enoate

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: 3M Company, Lot 1
- Expiration date of the lot/batch: 30 November, 2016
- Purity test date: 25 September, 2015

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Stable
- Stability under test conditions: Stable
- Solubility and stability of the test substance in the solvent/vehicle: Not indicated
- Reactivity of the test substance with the solvent/vehicle of the cell culture medium: Not indicated

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: The test article was dissolved in Acetone/Olive oil (4:1 v/v)

FORM AS APPLIED IN THE TEST: The test article was dissolved in Acetone/Olive oil (4:1 v/v)

In vivo test system

Test animals

Species:

mouse

Strain:

CBA:J

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Janvier, Le Genest-Saint-Isle, France
- Females (if applicable) nulliparous and non-pregnant: Yes
- Microbiological status of animals, when known: At least prior to dosing. It was ensured that the animals were healthy and that the ears were intact and free from any abnormality.
- Age at study initiation: Approx. 10 weeks old
- Weight at study initiation: within 20% of the sex mean
- Housing: Animals were group housed in labeled Makrolon cages (MIII type; height 18 cm) containing sterilised sawdust as bedding material (Lignocel S 8-15, JRS - J.Rettenmaier & Söhne GmbH + CO. KG, Rosenberg, Germany). Paper (Enviro-dri, Wm. Lillico & Son (Wonham Mill Ltd), Surrey, United Kingdom) and shelters (disposable paper corner home, MCORN 404, Datesand Ltd, USA) were supplied as cage-enrichment. The acclimatization period was at least 5 days before the start of treatment under laboratory conditions. On Day 6, the animals were group housed in Makrolon MII type cages with a sheet of paper instead of sawdust and cage enrichment.
- Diet (e.g. ad libitum): Free access to pelleted rodent diet (SM R/M-Z from SSNIFF® Spezialdiäten GmbH, Soest, Germany).
- Water (e.g. ad libitum): Free access to tap water.
- Acclimation period: At least 5 days
- Indication of any skin lesions: No lesions were observed.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18-24
- Humidity (%): 40-70
- Air changes (per hr): At least 10
- Photoperiod (hrs dark / hrs light): 12/12
- IN-LIFE DATES: From: 02 December, 2015 To: 21 December, 2015

Study design: in vivo (LLNA)

Vehicle:

acetone/olive oil (4:1 v/v)

Concentration:

0 (vehicle control), 10, 25, 50%

No. of animals per dose:

5

Details on study design:

PRE-SCREEN TESTS:
- Compound solubility:
- Irritation: Very slightly irritation (10% Days 2-4; 25% and 50% Days 1-4) of the ears was considered not to have a toxicologically significant effect on the activity of the nodes.
- Systemic toxicity: In the pre-screen test no significant irritation was seen, but hunched posture was observed in both animals treated with 100% test article.
- Ear thickness measurements: Ear thickness measurements were conducted using a digital thickness gauge (Kroeplin C110T-K) prior to dosing on Days 1 and 3, and on Day 6.
- Erythema scores: erythema scores were grade 2 or less.

MAIN STUDY

ANIMAL ASSIGNMENT AND TREATMENT
- Name of test method: Local Lymph Node Assay (LLNA)
- Criteria used to consider a positive response: The test article is considered a skin sensitizer if the results indicate it elicited a Stimulation Index (SI) greater than or equal to 3.

TREATMENT PREPARATION AND ADMINISTRATION:
The test article was prepared in Acetone/Olive oil (4:1 v/v).

The test item preparations (w/w) were prepared within 4 hours prior to each dosing. No adjustment was made for specific gravity of the vehicle. Homogeneity was assessed by visual inspection of the solutions.

Positive control substance(s):

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

Results and discussion

Positive control results:

this batch of animals and with the procedures used for this study.
The six-month reliability check with Alpha-hexylcinnamaldehyde indicates that the Local Lymph Node Assay as performed at WIL Research Europe is an appropriate model for testing for contact hypersensitivity.

In vivo (LLNA)

Results

Results 1

Parameter:

SI

Value:

0.8

Test group / Remarks:

10% Concentration

Results 2

Parameter:

SI

Value:

2.2

Test group / Remarks:

25% Concentration

Results 3

Parameter:

SI

Value:

3.3

Test group / Remarks:

50% Concentration

Results 4

Key result

Parameter:

EC3

Value:

43.2

Cellular proliferation data / Observations:

DETAILS ON STIMULATION INDEX CALCULATION
A Stimulation Index (SI) is calculated for each group using the individual SI values. The individual SI is the ratio of the DPM/animal compared to the DPM/vehicle control group mean.

EC3 CALCULATION
The EC3 values (the estimated test item concentration that will give a SI =3) were determined, using linear interpolation

CLINICAL OBSERVATIONS
No mortality occurred and no clinical signs of systemic toxicity were observed in any of the animals.

BODY WEIGHTS
Body weights and body weight gain of experimental animals remained in the same range as the controls over the study period.

Applicant's summary and conclusion

Interpretation of results:

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

Conclusions:

The skin sensitization potential of the test article was evaluated in a local lymph node assay per OECD 429 and GLP. In the pre-screen test no significant irritation was seen, but hunched posture was observed in both animals treated with 100% test article. Therefore, test article concentrations of 10, 25, and 50% were tested in the main test (vehicle: acetone:olive oil 4:1), along with a concurrent positive control (25% alpha-hexylcinnamaldehyde in acetone:olive oil). The stimulation indices of the test article at the three concentrations were 0.8, 2.2, and 3.3, and the EC3 was determined to be 43.2%. The stimulation index of the concurrent positive control was 6.5. The results of the study (EC3 = 43.2%) indicate that the test article is a Category 1B skin sensitizer according to GHS.

Executive summary:

The skin sensitization potential of the test article was evaluated in a local lymph node assay per OECD 429 and GLP. In the pre-screen test no significant irritation was seen, but hunched posture was observed in both animals treated with 100% test article. Therefore, test article concentrations of 10, 25, and 50% were tested in the main test (vehicle: acetone:olive oil 4:1), along with a concurrent positive control (25% alpha-hexylcinnamaldehyde in acetone:olive oil). The stimulation indices of the test article at the three concentrations were 0.8, 2.2, and 3.3, and the EC3 was determined to be 43.2%. The stimulation index of the concurrent positive control was 6.5. The results of the study (EC3 = 43.2%) indicate that the test article is a Category 1B skin sensitizer according to GHS.