Fatty acids, C8-18 and C18-unsatd., esters with neopentyl glycol

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

29 Nov - 20 Dec 2011

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP-Guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.42 (Skin Sensitisation: Local Lymph Node Assay)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

The department of health of the government of the United Kingdom

Type of study:

mouse local lymph node assay (LLNA)

Test material

Test material information

Constituent 1

Reference substance name:

Fatty acids, C8-18 and C18-unsatd., esters with neopentyl glycol

EC Number:

286-072-6

EC Name:

Fatty acids, C8-18 and C18-unsatd., esters with neopentyl glycol

Cas Number:

85186-86-3

Molecular formula:

Not applicable (UVCB substance).

IUPAC Name:

Fatty acids, C8-18 (even numbered) and C18-unsatd., esters with neopentyl glycol

Details on test material:

- Physical state: yellow liquid
- Analytical purity: not given
- Lot/batch No.: OE10817
- Expiration date of the lot/batch: 21.10.2016
- Storage condition of test material: room temperature in the dark

In vivo test system

Test animals

Species:

mouse

Strain:

other: CBA/Ca (CBA/CaOlaHsd)

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Harlan Laboratories UK Ltd., Oxon, UK
- Age at study initiation: 8 to 12 weeks
- Weight at study initiation: 15 to 23 g
- Housing: individually housed in suspended solid-floor polypropylene cages furnished with softwood woodflakes
- Diet: 2014C Teklad Global Rodent diet, ad libitum (Harlan Laboratories UK Ltd., Oxon, UK)
- Water: tap water, ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 - 25
- Humidity (%): 30 - 70
- Air changes (per hr): 15
- Photoperiod (hrs dark / hrs light): 12/12

Study design: in vivo (LLNA)

Vehicle:

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

Concentration:

25, 50, 100 % (v/v)

No. of animals per dose:

4

Details on study design:

RANGE FINDING TESTS:
- Compound solubility: solution in acetone/olive oil 4:1 prepared because it produced the most suitable formulation at required concentration
- Irritation: no visual local irritation or irritation by an equal to or greater than 25% increase in mean ear thickness

MAIN STUDY
ANIMAL ASSIGNMENT AND TREATMENT
- Name of test method: ³H-Methyl Thymidine
- Criteria used to consider a positive response: the test item will be regarded as a sensitizer if at least on concentration of the test item results in a threefold or greater increase in 3HTdR incorporation compared to control values. Any test item failing to produce a threefold or greater increase in 3HTdR incorporation will be classified as "non-sensitizer".

TREATMENT PREPARATION AND ADMINISTRATION:
Groups of 4 mice were treated with the undiluted test item or the test item at concentrations of 50% or 25% v/v in acetone/olive oil 4:1 by daily application of 25 µl to the dorsal surface of each ear for three consecutive days (Day 1, 2, 3). Five days following the first topical application of the test item or vehicle (Day 6) all mice were injected via the tail vein with 250 µl of phosphate buffered saline (PBS) containing ³H-methyl thymidine. Five hours later the draining auricular lymph nodes were excised and pooled for each treatment group. To precipitate out the radioactive material, the pellet was resuspended in 3 mL of 5 % trichloracetic acid (TCA).

Positive control substance(s):

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

Results and discussion

Positive control results:

The positive control Hexylcinnamaldehyde 25 % (v/v) in acetone/olive oil 4:1 a positive result in 5 animals with a SI value of 4.05.

In vivo (LLNA)

Results

Results 1

Parameter:

SI

Remarks on result:

other: The stimulation index for 25, 50 and 100 % test item was calculated as 2.45, 1.49 and 1.68, respectively.

Results 2

Parameter:

other: disintegrations per minute (DPM)

Remarks on result:

other: Disintegrations per minute were slightly increased by the test item, however no dose dependent increase was seen (see table1).

Any other information on results incl. tables

Table1: results of LLNA

test item
[% v/v]	dpm	SI
vehicle	9652.68	na
25	23618.86	2.45
50	14422.08	1.49
100	16232.34	1.68

na = Not applicable

Applicant's summary and conclusion

Interpretation of results:

not sensitising

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

DSD: not classified
CLP: not classified