Trehalose

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

19 Mar 2001 - 29 Jun 2001

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2001

Report date:

2001

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.4 (Acute Toxicity: Dermal Irritation / Corrosion)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Trehalose

EC Number:

202-739-6

EC Name:

Trehalose

Cas Number:

99-20-7

Molecular formula:

C12H22O11

IUPAC Name:

trehalose

Test material form:

solid: crystalline

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: 9F22
- Expiration date of the lot/batch: 22 June 2002
- Purity test date: not stated

RADIOLABELLING INFORMATION (if applicable)
not applicable

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: room temperature in the dark
- Stability under test conditions: assumed stable
- Solubility and stability of the test substance in the solvent/vehicle: assumed stable
- Reactivity of the test substance with the solvent/vehicle of the cell culture medium: assumed stable

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
none

FORM AS APPLIED IN THE TEST (if different from that of starting material)
applied as received

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Harlan UK Ltd, Bicester, Oxon, England
- Age at study initiation: 14 weeks
- Weight at study initiation: 2.9 to 3.1 kg
- Housing: individually
- Diet (e.g. ad libitum): standard, ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 +- 2 °C
- Humidity (%): 30-70 %
- Air changes (per hr): not stated
- Photoperiod (hrs dark / hrs light): 12 / 12

Test system

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

0.5 g

Duration of treatment / exposure:

initially one animal was treated at three sites for 3 min, 1 hour and 4 hours.
two further animals were treated for 4 hours.

Observation period:

immediately after removal of substance, 1 hour, 24, 48 and 72 hours

Number of animals:

3

Details on study design:

TEST SITE
- Area of exposure: 25 * 25 mm
- % coverage: not stated
- Type of wrap if used: 2-ply 25 mm x 25 mm porous gauze pad,
which had been moistened with 0.5 ml distilled water,
"Elastoplast" elastic adhesive dressing

REMOVAL OF TEST SUBSTANCE
- Washing (if done): yes
- Time after start of exposure: after 3 min, 1 hour, 4 hour respectively

OBSERVATION TIME POINTS
(indicate if minutes, hours or days) immediately, 1, 24, 48, 72 hours

SCORING SYSTEM:
- Method of calculation:
Local dermal irritation was assessed using the prescribed numerical system:
Erythema and eschar formation:
0 No erythema
1 Very slight erythema (barely perceptible)
2 Well-defined erythema
3 Moderate to severe erythema
4 Severe erythema (beet redness) or eschar formation preventing grading of erythema
Oedema formation:
0 No oedema
1 Very slight oedema (barely perceptible)
2 Slight oedema (edges of area well-defined by definite raising)
3 Moderate oedema (raised approximately I mm)
4 Severe oedema (raised more than I mm and extending beyond the area of exposure)

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

fully reversible

Results 2

Irritation parameter:

edema score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

fully reversible

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

A single semi-occlusive application of Trehalose to intact rabbit skin for three minutes. one hour or
four hours elicited no dermal irritation.

Executive summary:

A study was performed to assess the skin irritation potential of T rehalose to the rabbit. The method

followed was that described in:

EEC Methods for the determination of toxicity. Annex to Directive 92/69/EEC (Official Journal

No. L383A, 29.12.92), Part B, Method B.4. Acute toxicity (Skin Irritation).

OECD Guideline for Testing of Chemicals No. 404 "'Acute Dermal Irritation/Corrosion". Adopted

17 July 1992.

EPA Health Effects Test Guidelines OPPTS 870.2500 Acute Dermal Irritation EPA 712-C-98-196.

August 1998.

Three rabbits were each administered a single dermal dose of approximately 0.5 g of the test substance

and observed for four days. The effects of a three minute, 60 minute and four hour exposure were initially

investigated using a screen animal.

No dermal irritation was observed following a single semi-occlusive application of Trehalose to intact

rabbit skin for three minutes, one hour or four hours.

The means of scores for these reactions at approximately 24, 48 and 72 hours after administration,

calculated separately for each animal, are summarised below:

Means of scores at approximately 24, 48 and 72 hours
Animal number	Erythema	Oedema
2507	0	0
2508	0	0
2509	0	0