2(3H)-Furanone, dihydro-3-hydroxy-4,4-dimethyl-, (3S)-

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Study period:

2004-10-26 to 2005-02-04

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: OECD guideline compliant GLP compliant

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2005

Report date:

2005

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Version / remarks:

as at 1992

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.6 (Skin Sensitisation)

Version / remarks:

as at 1996

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2600 (Skin Sensitisation)

Version / remarks:

as at 2003

Deviations:

no

Test guideline 4

Qualifier:

according to guideline

Guideline:

other: Japanese Ministry of Agriculture, Forestry and Fisheries (JMAFF), 12 Nousan, Notification No 8147, November 2000, including the most recent partial revisions.

Deviations:

no

GLP compliance:

yes

Type of study:

guinea pig maximisation test

Test material

Test material information

Constituent 1

Reference substance name:

DL-alpha-Hydroxy-beta, beta-dimethyly-butyrolacton

IUPAC Name:

DL-alpha-Hydroxy-beta, beta-dimethyly-butyrolacton

Constituent 2

Reference substance name:

DL-Lactone

IUPAC Name:

DL-Lactone

Constituent 3

Reference substance name:

DL-Pantlactone

IUPAC Name:

DL-Pantlactone

Constituent 4

Reference substance name:

RS-Pantolactone

IUPAC Name:

RS-Pantolactone

Constituent 5

Reference substance name:

(±)-dihydro-3-hydroxy-4,4-dimethylfuran-2(3H)-one

EC Number:

201-210-7

EC Name:

(±)-dihydro-3-hydroxy-4,4-dimethylfuran-2(3H)-one

Cas Number:

79-50-5

IUPAC Name:

3-hydroxy-4,4-dimethyldihydrofuran-2(3H)-one

Details on test material:

- Name of test material (as cited in study report): dl-Lactone
- Physical state: white crystalline mass
- Analytical purity: 99.6 %
- Purity test date: not reported
- Lot/batch No.: 451
- Expiration date of the lot/batch: 30 September 2005
- Stability under test conditions: Stable under storage conditions, Stability in vehicle (water) at least for 4 h
- Storage condition of test material: In refrigerator in the dark

In vivo test system

Test animals

Species:

guinea pig

Strain:

Dunkin-Hartley

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Charles River Deutschland, Kisslegg, Germany
- Age at study initiation: approx. 4 weeks (nulliparous and non-pregnant)
- Weight at study initiation: 337 - 410 g (on day 1 of testing period)
- Housing: Group housing of maximally 5 animals per labelled cage (74 cm x 54 cm x 25 cm height) containing sterilised sawdust as bedding material (Woody-Clean type 3/4; Tecnilab-BMI BV, Someren , The Netherlands).
- Diet (e.g. ad libitum): ad libitum, standard guinea pig diet, including ascorbic acid (1000 mg/kg); (Charles River Breeding and Maintenance Diet for
Guinea Pigs, Altromin, Lage, Germany) + hay (B.M.I., Helmond, The Netherlands) provided at least twice a week.
- Water (e.g. ad libitum): ad libitum, tap water
- Acclimation period: at least 5 d

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21.0 ± 3.0 (actual range: 19.3 - 21.8),
- Humidity (%): 30-70 (actual range: 45 - 91)
- Air changes (per hr): ca. 15
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: Start: 26 October 2004, Completion: 26 November 2004

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

intradermal and epicutaneous

Vehicle:

water

Induction 2

Concentration / amount:

INDUCTION
Intradermal injection:
A. 1:1 Mixture of FCA and water for injection.
B. A 5% test substance concentration (Experimental); vehicle (Control).
C. 1:1 Mixture of FCA and a 10% concentration (Experimental) or vehicle (Control).
Epidermal exposure:
D. A 50% test substance concentration (Experimental); vehicle (Control).
CHALLENGE
50% test substance concentration (Experimental); vehicle (Control).

Challenge

Challenge 1

Route:

epicutaneous, semiocclusive

Vehicle:

water

Challenge 2

Concentration / amount:

INDUCTION
Intradermal injection:
A. 1:1 Mixture of FCA and water for injection.
B. A 5% test substance concentration (Experimental); vehicle (Control).
C. 1:1 Mixture of FCA and a 10% concentration (Experimental) or vehicle (Control).
Epidermal exposure:
D. A 50% test substance concentration (Experimental); vehicle (Control).
CHALLENGE
50% test substance concentration (Experimental); vehicle (Control).

No. of animals per dose:

controls: 5
treated group: 10

Details on study design:

RANGE FINDING TESTS:
Intradermal injection: one animal injected with 50 % and 20 % of test item in vehicle (water) at different sites (0.1 ml/site); one animal injected with 10 % and 5 % of test item in vehicle (water) at different sites 0.1 ml/site);
Epidermal exposure: two animals exposed for 24 h semi-occlusively with 50 % and 20 % of test item in vehicle (water) at different sites (0.5 ml each); two animals exposed for 24 h semi-occlusively with 10 % and 5 % of test item in vehicle (water) at different sites (0.5 ml each);

Exposure conditions same as for main experiment (see below)

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: once intradermally, once epidermally
- Exposure period: intradermal injection on day 3, epidermal exposure on day 10 for 24 h
- Test groups: 10 females
- Control group: 5 females
- Site: scapular
- Frequency of applications: single intradermal injection, single epidermal exposure
- Duration: see "exposure period" above
- Concentrations: see "Concentration" above
- Approximately 24 hours before the epidermal induction exposure all animals were treated with 10% SDS.
- Coverage for epidermal exposure: 2 x 3 cm² metalline patch (Lohmann GmbH, Neuwied, Germany), mounted on Micropore tape (3M, St. Paul, Minnesota, U.S.A. (Micropore and Coban), which was wrapped around the abdomen and secured with Coban elastic bandage (3M, St. Paul, Minnesota, U.S.A. (Micropore and Coban).


B. CHALLENGE EXPOSURE
- No. of exposures: once
- Day(s) of challenge: 22
- Exposure period: 24 h
- Test groups: 10 females
- Control group: 5 females
- Site: flank
- Concentrations: see "Concentration" above
- Evaluation (hr after challenge): 24 and 48 h after removal of dressing

OTHER OBSERVATIONS
Mortality/Viability was controlled twice daily.
Toxicity was observed at least once daily.
Body Weight was measured on day 1 and at termination.

Challenge controls:

- no naive controls were used
- controls received same treatment as exposure group except that animal received only the vehicle (water) instead of the test item solution

Positive control substance(s):

no

Results and discussion

In vivo (non-LLNA)

Results

Results 1

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

0

No. with + reactions:

0

Total no. in group:

5

Clinical observations:

none

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: negative control. Dose level: 0. No with. + reactions: 0.0. Total no. in groups: 5.0. Clinical observations: none.

Results 2

Reading:

2nd reading

Hours after challenge:

48

Group:

negative control

Dose level:

0

No. with + reactions:

0

Total no. in group:

5

Clinical observations:

none

Remarks on result:

other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: negative control. Dose level: 0. No with. + reactions: 0.0. Total no. in groups: 5.0. Clinical observations: none.

Results 3

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

50 % (w/v)

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

none

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 50 % (w/v). No with. + reactions: 0.0. Total no. in groups: 10.0. Clinical observations: none.

Results 4

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

50 % (w/v)

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

none

Remarks on result:

other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 50 % (w/v). No with. + reactions: 0.0. Total no. in groups: 10.0. Clinical observations: none.

Any other information on results incl. tables

- Table 1: Preliminary Irritation Study, Skin Reactions after Intradermal Injection

Animal number	Conc %	24 hours after injection		48 hours after injection
		Erythema, (grade)	Necrosis, (mm)	Erythema, (grade)	Necrosis, (mm)
88	50		8		9
	20		5		6
89	10		2		2
	5	1		1

Table 2: Preliminary Irritation Study,Skin Reactions after Epidermal Exposure

Animal number	Conc %	24 hours after exposure		48 hours after exposure
		Erythema, (grade)	Necrosis, (mm)	Erythema, (grade)	Necrosis, (mm)
86	50	0	0	0	0
	20	0	0	0	0
87	50	0	0	0	0
	20	0	0	0	0
88	10	0	0	0	0
	5	0	0	0	0
89	10	0	0	0	0
	5	0	0	0	0

- Table 3: Induction Readings

Animal Number		Intradermal injection (Day 3) A					Epidermal exposure (Day 10)
Control	E	N	E	N	E	N	Erythema	Oedema
71	2	0	0	0	2	0	0	0
72	2	0	0	0	1	0	0	0
73	2	0	0	0	1	0	0	0
74	2	0	0	0	1	0	0	0
75	2	0	0	0	2	0	0	0
Experimental	E	N	E	N	E	N
76	2	0	0	0	1	0	0	0
77	2	0	1	0	2	0	0	0
78	2	0	1	0	2	0	0	0
79	3	0	1	0	2	0	0	0
80	2	0	1	0	2	0	0	0
81	2	0	1	0	2	0	1	0
82	2	0	0	1	0	2	0	0
83	2	0	1	0	0	3	0	0
84	3	0	1	0	0	3	0	0
85	3	0	1	0	0	4	0	0

A: 1:1 Mixture of FCA and water for injection.

Skin effects intradermal injections:

E: Erythema (grade)

N: Signs of necrosis (mm in diameter)

- Table 4: Challenge Readings

Animal number	DAY 24		DAY 25
	50%#	Vehicle*	50%#	Vehicle*
Control
71	0	0	0	0
72	0	0	0	0
73	0	0	0	0
74	0	0	0	0
75	0	0	0	0
Experimental
76	0	0	0	0	not sensitised
77	0	0	0	0	not sensitised
78	0	0	0	0	not sensitised
79	0	0	0	0	not sensitised
80	0	0	0	0	not sensitised
80	0	0	0	0	not sensitised
81	0	0	0	0	not sensitised
82	0	0	0	0	not sensitised
83	0	0	0	0	not sensitised
84	0	0	0	0	not sensitised
85	0	0	0	0	not sensitised

#: Test substance concentration.

*: Water (Milli-U)

Applicant's summary and conclusion

Interpretation of results:

not sensitising

Remarks:

Migrated information

Conclusions:

RS-Pantolactone was tested for its skin sensitization potential according to OECD 406 following the GPMT test setting. The test item did not show any skin sensitisation potential in guinea pigs.

Executive summary:

RS-Pantolactone (named D,L-Lactone in the study report) was tested for its skin sensitization potential according to OECD 406 following the GPMT test setting, EC Commission Directive 96/54/EC, Part B.6, "Skin Sensitisation" (1996), EPA OPPTS 870.2600 "Skin Sensitisation" (2003) and JMAFF: Japanese Test Guidelines (2000) including the most recent partial revisions, and was based on the method described by Magnusson and Kligman, "Allergic Contact Dermatitis in the Guinea Pig - Identification of Contact Allergens" (1970).

Test substance concentrations selected for the main study were based on the results of a preliminary study.

In the main study, ten experimental animals were intradermally injected with a 5% concentration and epidermally exposed to a 50% concentration. Five control animals were similarly treated, but with vehicle alone (water). Injection sites treated with FCA showed transient erythema of grades 1 to 2 in both groups. Approximately 24 hours before the epidermal induction exposure all animals were treated with 10% SDS. Two weeks after the epidermal application all animals were challenged with a 50% test substance concentration and the vehicle.

There was no evidence that RS-Pantolactone had caused skin hypersensitivity in the guinea pig, since no responses were observed in the experimental animals in the challenge phase.

This result indicates a sensitisation rate of 0 per cent.

By expert judgment it is conclude that L-Pantolactone is not sensitising on skin.