Methyl ricinoleate

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

18 Mar -19 Apr 1999

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1999

Report date:

1999

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Deviations:

no

GLP compliance:

yes

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

The LLNA guideline study was not validated at the time the guinea pig maximisation test was performed (1999).

Test material

Test material information

Constituent 1

Reference substance name:

Methyl ricinoleate

EC Number:

205-472-3

EC Name:

Methyl ricinoleate

Cas Number:

141-24-2

Molecular formula:

C19H36O3

IUPAC Name:

methyl ricinoleate

Test material form:

liquid: viscous

In vivo test system

Test animals

Species:

guinea pig

Strain:

Dunkin-Hartley

Sex:

male/female

Details on test animals and environmental conditions:

TEST ANIMALS- Source: Charles River France, 76410 Saint-Aubin-lès-Elbeuf, France- Females nulliparous and non-pregnant: yes- Age at study initiation: approximately 3 months - Weight at study initiation: 382 ± 14 g (males); 357 ± 10 g (females)- Housing: The animals were housed individually in polycarbonate cages (48 cm x 27 cm x 20 cm) equipped with a polypropylene bottle. Dust-free sawdust was provided as litter (SICSA, 92142 Alfortville, France).- Diet: 106 pelleted diet (UAR, 91360 Villemoisson­ sur-Orge, France), ad libitum- Water: filtered drinking water (FG Millipore membrane (0.22 micron)), ad libitum- Acclimation period: at Ieast 5 days ENVIRONMENTAL CONDITIONS- Temperature (°C): 21 ± 2- Humidity (%): 30 - 70- Air changes (per hr): approximately 12 - Photoperiod (hrs dark / hrs light): 12/12

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

intradermal

Vehicle:

corn oil

Concentration / amount:

25%

Induction 2

Route:

epicutaneous, occlusive

Vehicle:

unchanged (no vehicle)

Concentration / amount:

0.5 mL

Day(s)/duration:

24 h

Challenge

Route:

epicutaneous, occlusive

Vehicle:

unchanged (no vehicle)

Concentration / amount:

0.5 mL

Day(s)/duration:

24 h

No. of animals per dose:

5 males and 5 females (controls), 10 males and 10 females (treated)

Details on study design:

MAIN STUDY A. INDUCTION EXPOSURE - No. of exposures: 2 (intradermal and epicutaneous, respectively) - Exposure period: single injection (intradermal) and 48 h (epicutaneous) - Test groups: On day 1, intradermal injections of Freund's complete adjuvant mixed with the test substance at a concentration of 10% (w/w) in corn oil (treated group) or the vehicle (control group) were performed in the interscapular region.On day 7, the same region received a topical application of sodium lauryl sulfate in vaseline (10%, w/w) in order to induce local irritation.On day 8, the undiluted test substance (treated group) or the vehicle (control group) was applied to the same test site which was then covered by an occlusive dressing for 48 hours. B. CHALLENGE EXPOSUREOn day 22, after a rest period of 12 days, all animals of the treated and control groups were challenged by a cutaneous application of the undiluted test substance to the right flank. The left flank served as control and received the vehicle only. Test substance and vehicle were maintained under an occlusive dressing for 24 hours.Skin reactions were evaluated approximately 24 and 48 hours after removal of the dressing. At the end of the study, animals were killed without examination of internal organs. No skin samples were taken from the challenge application sites.The sensitivity of the guinea pigs in CIT experimental conditions was checked with a positive sensitizer, 2,4-Dinitro Chlorobenzene (DNCB). During the induction period, the reference substance DNCB was applied at the concentrations of 0.1% (w/w) (day 1) and 1% (w/w) (day 8) in corn oil. For the challenge application, the reference substance DNCB was applied at the concentration of 1% (w/w) in corn oil.

Challenge controls:

Challenge (all groups)topical application: RICINOLEATE DE METHYLE undiluted.

Positive control substance(s):

yes

Remarks:

2,4-Dinitro chlorobenzene (DNCB)

Results and discussion

Positive control results:

The species and strain which were used showed a satisfactory sensitization response in 90% animals treated with DNCB.

In vivo (non-LLNA)

Results

Results 1

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

Induction: 25 and 100%; challenge: 100%

No. with + reactions:

0

Total no. in group:

20

Clinical observations:

very slight erythema observed in 1/10 controls and 5/20 treated animals

Remarks on result:

no indication of skin sensitisation

Results 2

Key result

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

Induction: 25 and 100%; challenge: 100%

No. with + reactions:

0

Total no. in group:

20

Remarks on result:

no indication of skin sensitisation

Results 3

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

Induction: 0%; challenge: 100%

No. with + reactions:

0

Total no. in group:

5

Results 4

Key result

Reading:

2nd reading

Hours after challenge:

48

Group:

negative control

Dose level:

Induction: 0%; challenge: 100%

No. with + reactions:

0

Total no. in group:

5

Any other information on results incl. tables

Table 1: Scores of the control group

	Animal number	24 h				48 h
		Erythema		Oedema		Erythema		Oedema
		Left flank	Right Flank	Left flank	Right Flank	Left flank	Right Flank	Left flank	Right Flank
Male	31	0	0	0	0	0 / S	0 / S	0	0
	32	0	0	0	0	0	0	0	0
	33	0	0	0	0	0	0	0	0
	34	0	0	0	0	0	0 / S	0	0
	35	0	0	0	0	0 / S	0 / S	0	0
Female	46	0	0	0	0	0	0 / S	0	0
	47	0	0	0	0	0	0	0	0
	48	0	0	0	0	0	0 / S	0	0
	49	0	0	0	0	0	0	0	0
	50	0	0	0	0	0	0 / S	0	0

S: Dryness of skin

Table 2: Scores of the treatment group

	Animal number	24 h				48 h
		Erythema		Oedema		Erythema		Oedema
		Left flank	Right Flank	Left flank	Right Flank	Left flank	Right Flank	Left flank	Right Flank
Male	36	0	1	0	0	0	0 / S	0	0
	37	0	0	0	0	0	0 / S	0	0
	38	0	0	0	0	0	0 / S	0	0
	39	0	0	0	0	0	0	0	0
	40	0	0	0	0	0	0	0	0
	41	0	0	0	0	0	0 / S	0	0
	42	0	1	0	0	0	0 / S	0	0
	43	0	0	0	0	0	0	0	0
	44	0	0	0	0	0 / S	0 / S	0	0
	45	0	0	0	0	0	0	0	0
Female	51	0	0	0	0	0	0 / S	0	0
	52	0	1	0	0	0	0 / S	0	0
	53	0	0	0	0	0	0	0	0
	54	0	0	0	0	0	0	0	0
	55	0	0	0	0	0	0	0	0
	56	0	0	0	0	0	0	0	0
	57	0	0	0	0	0 / S	0	0	0
	58	0	0	0	0	0	0	0	0
	59	0	1	0	0	0 / S	0 / S	0	0
	60	0	0	0	0	0	0 / S	0	0

S: Dryness of skin

Applicant's summary and conclusion

Interpretation of results:

other: CLP/EU GHS criteria not met, no classification required according to Regulation(EC) No. 1272/2008

Conclusions:

CLP: not classified

Executive summary:

The sensitization potential of the test substance was evaluated in the guinea pig according to the maximization procedure by Magnusson and Kligman. 20 Dunkin-Hartley guinea pigs (10 males and 10 females) were treated in the test group. The test substance was applied by intradermal injection at a concentration of 25% in corn oil, after 7 days, the animals were induced (and irritation by sodium lauryl sulfate in vaseline) epicutanously by the undiluted test item. On day 22, after a period of 12 days, treated animals and controls were challenged by a cutaneous application of the test substance to the right flank. The left flank served as control and received the vehicle only. Test substance and vehicle were maintained under an occlusive dressing for 24 h.

Skin reactions were evaluated approximately 24 and 48 h after removal of the dressing.

 

No symptoms, mortality or cutaneous reactions due to any sensitization process by treatment with the test substance were observed in guinea pigs.