4-O-β-D-galactopyranosyl-D-glucitol

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference

Reference 1

Reference Type:

study report

Title:

Unnamed

Year:

1981

Report date:

1981

Reference 2

Reference Type:

other: Published secondary source

Title:

Lactitol

Author:

WHO/FAO

Year:

1983

Bibliographic source:

WHO/FAO: Expert Committee on Food Additives Summary of Toxicological Data of Certain Food Additives Series 18 (http://www.inchem.org/documents/jecfa/jecmono/v18je10.htm)

Materials and methods

Principles of method if other than guideline:

The experiment was conducted according to the guinea pig maximization test, as described by B. Magnusson and A.M. Kligman, in "Allergic contact dermatitis in the guinea pig", Ed. Ch.C. Thomas, Springfield, Illinois, USA (1970).

GLP compliance:

not specified

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

Guinea pig data available prior to 2009.

Test material

Test material information

Constituent 1

Reference substance name:

4-O-β-D-galactopyranosyl-D-glucitol

EC Number:

209-566-5

EC Name:

4-O-β-D-galactopyranosyl-D-glucitol

Cas Number:

585-86-4

Molecular formula:

C12H24O11

IUPAC Name:

4-O-beta-D-galactopyranosyl-D-glucitol

Specific details on test material used for the study:

Test material:
- Sample of the material was taken from a batch of 950 kg which was received and stored at ambient temperature.
- Test material was a white crystalline powder containing 9.67% water and purity of more than 98% on the dry matter.

In vivo test system

Test animals

Species:

guinea pig

Strain:

other: SPF bred albino

Sex:

male

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Central Institute for the Breeding of Laboratory Animals TNO, Zeist, The Netherlands
- Weight at study initiation: 261 to 342 g
- Housing: individually housed in suspended stainless steel cages, fitted with wire mesh floors and fronts
- Diet (e.g. ad libitum): fed pelleted stock diet ad libitum
- Water (e.g. ad libitum): not reported
- Acclimation period: 1 day
- Indication of any skin lesions: no

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 23 ± 1⁰C
- Humidity (%): ≥40 %
- Photoperiod (hrs dark / hrs light): 12 hours light/dark cycle

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

intradermal and epicutaneous

Vehicle:

water

Concentration / amount:

Freund's complete adjuvant (FCA), 40% (w/v) dilution of the test substance in water, and 40% (w/v) dilution of the test substance in a mixture of FCA and water (1:1)

Day(s)/duration:

Three injections made simultaneously

Induction 2

Route:

epicutaneous, occlusive

Vehicle:

water

Concentration / amount:

40% (w/v) dilution of test substance in water

Day(s)/duration:

1 week after intradermal injections for 48 hours

Challenge

No.:

#1

Route:

epicutaneous, occlusive

Vehicle:

water

Concentration / amount:

20% (w/v) dilution of the test substance in water

Day(s)/duration:

2 weeks after topical induction for 24 hours

No. of animals per dose:

10/test substance; 5/negative control

Details on study design:

Preliminary Test:

For preliminary observations, guinea pigs were used that had already been served as controls in other sensitization tests. The intradermal and topical irritancy of a range of dilutions of the test substance were examined. The maximum concentration suitable for intradermal injection was found to be 40 % w/v in water, and for topical application 40% w/v in water.

Main study:

Induction Procedure-
Induction was in a two-stage operation consisting of firstly three pairs of injections made simultaneously and, secondly, one week later, a closed patch exposure performed over the injection sites. For this purpose, an area of dorsal skin 4 x 6 cm on the shoulder region was clipped free of hair with electric clippers.

Intradermal Injections-
Three pairs of intradermal injections were made in the clipped area of the animals. Preparations were made and injected into the skin of the test animals with skin readings made 24 hours after treatment.

Topical application-
One week after the injections were made, the same area of the skin was clipped again and closely shaved with an electric clipper and topically treated with the test substance. A 2 x 4 cm patch of filter paper was soaked in a 40 % (w/v) dilution of the test substance in water. The patch was placed on the skin and covered with a piece of PVC foil. This in turn was firmly secured by an elastic adhesive bandage wound round the torso of the animal. The end of the bandage was covered by self sticking tape. The dressing was left in place for 48 hours. The controls were treated in the same way, except that the patch was soaked in water. Skin readings were made after removal of the patches.

Challenge Procedure-
Both test and control animals were challenged two weeks after the topical induction as follows:
An area 5 x 5 cm on the left flank of the animal was clipped free of hair and closely shaved. Subsequently, a 2 x 2 cm patch of filter paper was soaked in a 20 % (w/v) dilution of the test substance in water. The patch was placed on the shaved area under a piece of PVC foil and secured. The dressing was kept in place for 24 hours. Skin readings were made at 0, 24 and 72 hours after removal of the patches. The reactions to the challenge were judged according to a method described by J.H. Draize, G. Woodard and H.O. Calvery (J. Pharmacol. exp. Therap. 82 (1944) 377-390). The sensitization was classified according to Magnusson and Kligman (1970).

Positive control substance(s):

no

Results and discussion

In vivo (non-LLNA)

Results

Results 1

Reading:

1st reading

Hours after challenge:

0

Group:

test chemical

Dose level:

20%

No. with + reactions:

2

Total no. in group:

10

Results 2

Reading:

2nd reading

Hours after challenge:

24

Group:

test chemical

Dose level:

20%

No. with + reactions:

0

Total no. in group:

10

Results 3

Reading:

1st reading

Hours after challenge:

0

Group:

negative control

Dose level:

0%

No. with + reactions:

0

Total no. in group:

5

Results 4

Reading:

2nd reading

Hours after challenge:

24

Group:

negative control

Dose level:

0%

No. with + reactions:

0

Total no. in group:

5

Results 5

Reading:

1st reading

Hours after challenge:

0

Group:

positive control

Remarks on result:

not measured/tested

Any other information on results incl. tables

All animals remained in good health during the experimental period. With Freund's Complete Adjuvant, there was slight erythema and slight edema in the test animals. With 40% dilution of the test substance in water and with water alone; slight erythema, in one test animal. With 40% dilution of the test substance in a mixture of FCA and water (1:1) and with the mixture alone: erythema, edema and abscesses. The topical application made with water in the control animals did not induce either erythema or edema. With a 40% dilution of the test substance in water,3 out of 10 test animals showed slight erythema. The challenge test with 20% of the test substance in water induced a slight allergic response reaction in 2 out of the 10 test animals. This reaction was observed only after the removal of the dressing. Twenty-four hours later none of the test animals showed any reaction. The controls did not show a positive reaction either directly after the removal of the dressing or 24 hours thereafter. On the basis of the results obtained, it appears that the test substance Lactitol exhibited slight sensitization properties according to the classification of Magnusson and Kligman.

Applicant's summary and conclusion

Conclusions:

Slight sensitization properties (Challenge with 20% induced a slight allergic response reaction in 2/10 test animals after removal of dressing. 0/10 animals showed reaction 24-hours later).

Executive summary:

A maximization test was carried out on 15 young male guinea-pigs. The maximum concentration of lactitol, suitable for intradermal injection and topical application, was found to be 40% w/v in water; these concentrations were utilized. From the reaction to the challenge dose, it was concluded that the test substance exhibited slight sensitization properties (challenge with 20% induced a slight allergic response reaction in 2/10 test animals after removal of dressing. 0/10 animals showed reaction 24-hours later).