Reaction products of enzymatic esterification of linolenic acid and 1,2-octanediol

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Remarks:

non-radioactive LLNA test method

Type of information:

experimental study

Adequacy of study:

key study

Study period:

12 April 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes (incl. QA statement)

Remarks:

quality assurance statement included

Type of study:

mouse local lymph node assay (LLNA): DA

Test material

Test material information

Constituent 1

Reference substance name:

1-hydroxyoctan-2-yl octadeca-9,12,15-trienoate; 2-hydroxyoctyl octadeca-9,12,15-trienoate; 2-hydroxyoctyl octadeca-9,12-dienoate; octane-1,2-diol

EC Number:

944-490-2

Molecular formula:

unknown

IUPAC Name:

1-hydroxyoctan-2-yl octadeca-9,12,15-trienoate; 2-hydroxyoctyl octadeca-9,12,15-trienoate; 2-hydroxyoctyl octadeca-9,12-dienoate; octane-1,2-diol

Test material form:

liquid

In vivo test system

Test animals

Species:

mouse

Strain:

CBA:J

Sex:

female

Details on test animals and environmental conditions:

Female nulliparous and non gravid, weighing between 18 g and 23.8 g, aged of 7-8 weeks.
Acclimatisation of 5 days minimum in the laboratory animal house where the experiment took place. Air-conditioned (20-24°C) room at relative humidity of 45-65% with non-recycled filtered air changed 10-15 times/h. Artificial day/night of 12 hours light and 12 hours darkness. Water ad libitum

Study design: in vivo (LLNA)

Vehicle:

other: olive oil

Concentration:

1%, 10%, 20%, 30%, 50%, chosen according to the results of the preliminary study

No. of animals per dose:

4 mice/dose (32 mice allocated to eight groups)

Details on study design:

Each mouse received a cutaneous application over the dorsal surface of both ears (25 μL) every 24 hours for three consecutive days (D1, D2 and D3). Recording of local reactions was made before each application and just before euthanasia. Ear thickness measurements were made before application (on D1), on D3 and on D6. Lymphoproliferative response was measured by incorporation of 5-bromo-deoxyuridine on D6. Then, animals were euthanased by CO2 inhalation in a CO2 chamber. The results were elucidated using an Elisa system on D7.

Positive control substance(s):

other: 2,4-Dinitrochlorobenzene (DNCB)

Statistics:

Dunnett's test (analysis of variance)

Results and discussion

Positive control results:

No change in body weight gain. Slight erythema of the ears observed from D4 to D6. DNCB showed a statistically significant increase in ear thickness of +18% between D1 and D6, a statistically significant Stimulation Index of 3 and a cellularity index of 6.11 with a total amount of viable cells per node of 13.06 x 10E6. Amount of cells, cellularity index and increase in ear thickness were within the range usually obtained for DNCB.
Consequently, all results obtained with DNCB at 0.5% in acetone/olive oil showed that the study could be considered as valid.

In vivo (LLNA)

Results

Key result

Parameter:

SI

Value:

>= 0 - < 3

Variability:

standard deviation not specified

Cellular proliferation data / Observations:

No change in body weight gain was seen whatever the group. No mortality nor clinical signs were recorded during the study.
No skin reaction in the 1%, 10% and 20% dose groups. Some animals treated with test item at 30% had slight erythema on D4 (5/8 ears) and D5 (4/8 ears).
Animals treated with test substance at 50% has slight erythema from D2 (6/8 ears) to D6 (8/8 ears) with an increase in ear thickness between D1 and D6 (+22%). In the preliminary study, a similar observation was seen at the same concentration tested. According to these results, test item at 50% could be considered as slightly irritant.
As the test item did not produce a stimulation index (SI) equal or greater than 3 whatever the dose tested, the EC3 value, defined as the theoretical concentration resulting in a SI value of 3, cannot be
calculated.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Under the experimental conditions adopted, the test substance at 1%, 10%, 20%, 30% and 50% in olive oil did not induce delayed contact hypersensitivity in the Local Lymph Node Assay using female CBA mice after three consecutive days of treatment.

Executive summary:

No induction of delayed contact hypersensitivity in the Local Lymph Node Assay, according to OECD 429 Guideline using 32 female CBA mice, stimulation index < 3.