Lyase, pectin

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 1999-02-15 to 1999-05-05

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Since the two enzymes are from the same enzyme sub-sublcass, similar results can be expected for pectin lyase.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1999

Report date:

1999

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Version / remarks:

1992

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: EEC

Version / remarks:

EEC (1992) Acute Toxicity (Skin irritation). Section B4 (L383A/124-L383A/127) of the Annex to
the European Communities Directive 92/69/EEC. The Official Journal of the European communities
L383A (vol. 35), 29 December 1992 (ISSN 0378-6978).

Deviations:

no

Principles of method if other than guideline:

During acclimatisation and experimental period the weight of two of the animals was up to 1/2 kg less than aimed in protocol. This was due to reduced water intake of especially rabbit No. 6 during the acclimatisation period. When the rabbits were offered water in a bowl the weight of rabbit No. 6 increased by 1/2 kg within three days. As the skin of all rabbits tested were without signs of dehydration this deviation from protocol are not considered to have had any influence on the conclusion of the study.

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Lyase, pectate

EC Number:

232-766-9

EC Name:

Lyase, pectate

Cas Number:

9015-75-2

Molecular formula:

Not available

IUPAC Name:

Pectate lyase IUBMB 4.2.2.2

Constituent 2

Reference substance name:

Protein as a constituent of enzyme deriving from the fermentation or extraction process

Molecular formula:

Not available

IUPAC Name:

Protein as a constituent of enzyme deriving from the fermentation or extraction process

Constituent 3

Reference substance name:

Inorganic salts as a constituent of enzyme deriving from the fermentation or extraction process

Molecular formula:

Not available.

IUPAC Name:

Inorganic salts as a constituent of enzyme deriving from the fermentation or extraction process

Constituent 4

Reference substance name:

Carbohydrates constituent of enzyme deriving from the fermentation or extraction process

Molecular formula:

Not available.

IUPAC Name:

Carbohydrates constituent of enzyme deriving from the fermentation or extraction process

Constituent 5

Reference substance name:

Lipids as a constituent of enzyme deriving from the fermentation or extraction process

Molecular formula:

Not available.

IUPAC Name:

Lipids as a constituent of enzyme deriving from the fermentation or extraction process

Test material form:

liquid

Details on test material:

- Lot/batch No.: PPE 6345
- Expiration date of the lot/batch: 2008-11-30
- Stability under test conditions: Stability at ambient temperature >4 hours
- Storage condition of test material: Stored below minus 18 degrees of C in the dark.

Test animals

Species:

rabbit

Strain:

other: Danish Landrace, albino

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Bred by Statens Seruminstitut "Hvidesten", Denmark
- Weight at study initiation: between 2.08 - 2.56 kg
- Age at study initiation: Young adults
- Housing: Individually, in animal room with control of temperature (20±3°C) and humidity (30-70%)
- Diet: 110 g standard diet per day (Altromin 2110, Standard Diet for Rabbits) ad libitum
- Water: Tap water ad libitum
- Acclimation period: 8 days for animal no. 1 and 3 and 14 days for animal no. 6
- Photoperiod (hrs dark / hrs light): 12 hrs/12hrs

IN-LIFE DATES:
From: 1999-02-22 To: 1999-03-05

Test system

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 mL
- Concentration (if solution): undiluted

Duration of treatment / exposure:

4 hours

Observation period:

0.5-1, 24, 48, 72 hrs

Number of animals:

3

Details on study design:

The test compound Pectate Lyase was assessed by semiocclusive application of 0.5 mL of the test material formulation to an area of 2.5 x 2.5 cm on the closel clipped flank of three male albino rabbits for 4 hrs.
The study was conducted to comply with the following guidelines:
- Organisation for Economic Co-operation and Development (OECD) test guideline 404.

TEST SITE
- Area of exposure: 2.5 x 2.5 cm
- Type of wrap if used: gauze patch and plaster

REMOVAL OF TEST SUBSTANCE
- Washing: Washed with water

OBSERVATION TIME POINTS
0.5-1, 24, 48, 72 hrs

SCORING SYSTEM:
- Method of calculation:
Erythema and eschar formation Grade
No erythema ...................................................................................................................................0
Very slight erythema (barely perceptible) ......................................................................................1
Defined erythema ............................................................................................................................2
Moderate to severe erythema .........................................................................................................3
Severe erythema (beet redness) to slight eschar formations (injuries in depth) ...........................4

Oedema formation
No oedema .......................................................................................................................................0
Very slight oedema (barely perceptible) ..........................................................................................1
Slight oedema (edges of area well defined by definite raising) .......................................................2
Moderate oedema (raised approximately 1 mm) ...............................................................................3

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

0

Results 2

Irritation parameter:

edema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

0

Results 3

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

0

Results 4

Irritation parameter:

edema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

0

Results 5

Irritation parameter:

erythema score

Basis:

animal #6

Time point:

24/48/72 h

Score:

0

Max. score:

0

Results 6

Irritation parameter:

edema score

Basis:

animal #6

Time point:

24/48/72 h

Score:

0

Max. score:

0

Irritant / corrosive response data:

No erythema, eschar formation or oedema was observed at the test sites at any of the six rabbits at the examinations 1, 24, 48 or 72 hours after termination of exposure.
Two rabbits showed skin reaction related to the outer rim of the application area where the skin was exposed to both plaster and test material. This is not considered as an effect related to irritative properties of the test material.

Other effects:

No other effects.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

There were no erythema or edema noted at any of the readings of the dermal reactions in treating rabbit skin (2.5 x 2.5 cm) with pectate lyase for 4 hours. Therefore, pectate lyase should not be classified as an irritant.

Executive summary:

The acute dermal irritant effect of pectate lyase was investigated according to the method recommended in the OECD Guideline No 404, “Acute Dermal Irritation/Corrosion”. The study was conducted in accordance with GLP. The study was performed on three male albino rabbits, Danish Landrace. They were each exposed to 0.5 mL of the undiluted liquid test item applied under semiocclusive conditions to each of three closely-clipped test sites, 2.5 x 2.5 cm. After a 4-hour exposure period, the test item was removed from the test site and the skin was examined.

Dermal reactions were scored at 0.5-1, 24, 48 and 72 hours after patch removal. There were no erythema or edema noted at any of the readings of the dermal reactions.

Under the conditions of this test and criteria of the EEC Directive, pectate lyase should not be classified.