Fatty acids, dehydrated castor-oil

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (LLNA)

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Guideline study with acceptable restrictions

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

2008

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

adopted 2002

Deviations:

yes

Remarks:

no results for range-finding study and for positive control presented; no data on ear swelling response presented;

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

EC 2004

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2600 (Skin Sensitisation)

GLP compliance:

yes

Type of study:

mouse local lymph node assay (LLNA)

Test material

Test material information

Constituent 1

Reference substance name:

Oleic acid

EC Number:

204-007-1

EC Name:

Oleic acid

Cas Number:

112-80-1

Molecular formula:

C18H34O2

IUPAC Name:

octadec-9-enoic acid

Details on test material:

- Name of test material (as cited in study report): oleic acid
- Analytical purity: 99%

In vivo test system

Test animals

Species:

mouse

Strain:

other: SPF-CBA/Ca01aHsd

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Harlan Winkelmann, Borchen, Germany
- Age at study initiation: 6 - 13 weeks
- Housing: Mice were housed in groups in Macrolon cages on Altromin saw fiber bedding
- Diet: Altromin 1324 maintenance diet for rats and mice, totally pathogen free, ad libitum
- Water: tap water, ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3
- Humidity (%): 55 ± 10
- Air changes (per hr): 10
- Photoperiod (hrs dark / hrs light): 12 / 12

Study design: in vivo (LLNA)

Vehicle:

other: acetone / olive oil (3 + 1 (v/v))

Concentration:

10, 25 and 50%

No. of animals per dose:

5

Details on study design:

RANGE FINDING TESTS:
A preliminary test was performed with 3 animals to detect the highest tolerable concentration. For this, 3 different concentrations were applied daily to the ears of the animals which were observed for local skin irritation (ear swelling measured on day 1 and 4) and systemic effects.

MAIN STUDY
ANIMAL ASSIGNMENT AND TREATMENT
- Name of test method: 3H-methyl thymidine incorporation determined by ß-scintillation
- Criteria used to consider a positive response: SI ≥ 3

TREATMENT PREPARATION AND ADMINISTRATION:
25 µl of the test or control solution was applied to the entire dorsal surface of each ear of each mouse. The application was repeated on days 2 and 3. On day 6, 20 µCi 3H-methyl thymidine was injected intravenously into the tail vein. Approximately 5 h later, the draining auricular lymph nodes were excised, weighed, individually pooled for each animal and collected in phosphate buffered saline (PBS). A single cell suspension of pooled lymph node cells was prepared by gentle mechanical disaggregation through polyamide gauze (200 mesh size). After washing with PBS, the cell suspension was pelleted. For further washing, cells were resuspended in PBS. After the final wash, each pellet was resuspended in approx. 1 mL 5% trichloracetic acid (TCA) and incubated at 4 °C overnight for precipitation of macromolecules. After washing, each precipitate was re-suspended in 10 mL scintillation fluid, transferred in scintillation vials and stored at room temeperature overnight.

Positive control substance(s):

other: p-phenylenediamine (1%)

Statistics:

Arithmetic mean values were calculated and one-sided Student´s t-tests (p < 0.01) were performed to evaluate statistical significance.

Results and discussion

In vivo (LLNA)

Results

Results 1

Parameter:

SI

Remarks on result:

other: The calculation revealed a bell-shaped dose-response curve with the SI at 50% test substance being lower than the SI at 25%. The SIs of 25 and 50% are above the threshold of 3 where as the SI for 10% test substance is lower than 3.

Results 2

Parameter:

other: disintegrations per minute (DPM)

Remarks on result:

other: no data

Any other information on results incl. tables

Table 1: Stimulation indices (SI) and lymph node weight indices (LNWI) after exposure to oleic acid

 

	10%	25%	50%
SI ± SD	2.6 ± 1.6	14.9 ± 6.8	6.9 ± 3.6
LNWI ± SD	1.1 ± 0.3	2.3 ± 0.2*	2.2 ± 0.2*

 

* Statistically significant increase compared to vehicle control (p < 0.01)

Applicant's summary and conclusion

Interpretation of results:

ambiguous

Remarks:

Migrated information Criteria used for interpretation of results: EU