Laccase

Endpoint summary

Description of key information

Laccase is neither a skin or an eye irritant.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Reference 1

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From June 28, 1996 to October 07, 1996

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to other study

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Version / remarks:

1992

Deviations:

no

GLP compliance:

yes

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Bred by Novo Nordisk A/S, Denmark
- Weight at study initiation: between 2.6-2.9 kg
- Age at study initiation: 21 wk old adults
- Housing: Individually, in animal room with control of temperature (17-23°C) and humidity (30-70%RH)
- Diet : Standard diet 130 g daily
- Water (e.g. ad libitum): tap water ad libitum
- Acclimation period: 6 days
- Photoperiod (hrs dark / hrs light): 12 hrs/12hrs

IN-LIFE DATES: From: 1996-07-09 To: 1996-07-15

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

physiological saline

Remarks:

500 mg of freeze-dried test batch PPX 5660, ca. 450 mg Total Organic Solids (TOS) was moistened with 0.9% w/v NaCl.

Controls:

not required

Amount / concentration applied:

470 mg TOS (total organic solid)

Duration of treatment / exposure:

4 h

Observation period:

6 days

Number of animals:

3

Details on study design:

TEST SITE
- Area of exposure: 2.5 x 2.5 cm
- Type of wrap if used: the patch was covered with Hansapor sterile wound dressing (Beiersdorf) and an elastic tubular support bandage was further applied to prevent the animals from damaging the patch.
REMOVAL OF TEST SUBSTANCE
- Washing (if done): yes, with water
- Time after start of exposure: 4 hrs

SCORING SYSTEM: According to the standard scoring system of OECD test guideline 404.

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

0

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0.7

Max. score:

1

Reversibility:

fully reversible within: 72 hrs

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

1

Max. score:

1

Reversibility:

fully reversible within: 6 days

Remarks on result:

other: No reading at day 4 and 5, so reactions might have cleared earlier.

Irritation parameter:

erythema score

Max. score:

1

Remarks on result:

other: Max. duration: 6d

Irritation parameter:

edema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

0

Irritation parameter:

edema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

0

Irritation parameter:

edema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

0

Irritation parameter:

edema score

Max. score:

0

Remarks on result:

other: Max. duration: 0 d; Max. value at end of observation period: 0 (related to all animals)

Irritant / corrosive response data:

Reversibility of any observed effect: Changes fully reversible within 6 days

Other effects:

No clinical reaction to treatment was observed throughout the study.

Interpretation of results:

GHS criteria not met

Conclusions:

In conclusion, laccase can be classified as non-irritant to the skin.

Executive summary:

In accordance with OECD guideline 404, a primary skin irritation test in rabbits was performed with Laccase, batch PPX 5660.The present batch was a light brown powder, a highly concentrated freeze-dried version of the liquid batch PPX 5326 used in the previous skin irritation study. The study was conducted in accordance with GLP.

On the intact skin of the clipped back of each the 3 rabbits, 0.5 g of the batch moistened with saline was applied under a patch of gauze (2.5 x 2.5 cm). A semiocclusive bandage was utilised and the adjacent areas of untreated skin served as control.

After 4 hours exposure the patches and the remaining test substance were removed by gentle washing, and the skin reaction, erythema-, eschar- and edema formation was evaluated ½-1, 24, 48 and 72 hours and also 6 days after. Slight reversible erythema reactions were noted in 2 rabbits, one of them up to day 3. Max score was 1. The reaction had cleared at the reading on day 6, however no reading was performed at day 4 and 5, so the reaction might have cleared earlier. No edema was seen in any of the animals.

 

In conclusion, laccase can be classified as non-irritant to the skin.

Reference 2

Endpoint:

skin irritation: in vitro / ex vivo

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

an in vitro skin irritation study does not need to be conducted because adequate data from an in vivo skin irritation study are available

Reference 3

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

From January 22, 1996 to March 13, 1996

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to other study

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Version / remarks:

1992

Deviations:

no

GLP compliance:

yes

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Bred by Novo Nordisk A/S, Denmark
- Weight at study initiation: between 2.3-2.4 kg
- Age at study initiation: 14 wk old adults
- Housing: Individually, in animal room with control of temperature (17-24°C) and humidity (30-70%RH)
- Diet : Standard diet 130 g daily
- Water (e.g. ad libitum): tap water ad libitum
- Acclimation period: 6 days
- Photoperiod (hrs dark / hrs light): 12 hrs/12hrs

IN-LIFE DATES: From: 1996-01-30 To: 1996-02-02

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Remarks:

Test batch used as is: 0.5 mL of density 1.024 g/ml and 6.6% Total Organic Solids (TOS), corresponding to 34 mg TOS.

Controls:

not required

Amount / concentration applied:

- Amount(s) applied (volume or weight with unit): 0.5 mL
- Concentration (if solution): undiluted, i.e. 34 mg Total Organic Solids (TOS)/ 0.5 mL

Duration of treatment / exposure:

4 h

Observation period:

72 h

Number of animals:

3

Details on study design:

TEST SITE
- Area of exposure: 2.5 x 2.5 cm
- Type of wrap if used: the patch was covered with 3M Micropore Surgical tape 1530-3 and an elastic tubular support bandage was further applied to prevent the animals from damaging the patch.
REMOVAL OF TEST SUBSTANCE
- Washing (if done): yes, with water
- Time after start of exposure: 4 hrs

SCORING SYSTEM: According to the standard scoring system of OECD test guideline 404.

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

other: overall at 24, 48 and 72 h

Score:

0

Max. score:

0

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

other: overall at 24, 48 and 72 h

Score:

0

Max. score:

0

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

other: overall at 24, 48 and 72 h

Score:

0

Max. score:

0

Irritation parameter:

erythema score

Max. score:

0

Remarks on result:

other: Max. duration: 0 d; Max. value at end of observation period: 0 (related to all animals)

Irritation parameter:

edema score

Basis:

animal #1

Time point:

other: overall at 24, 48 and 72 h

Score:

0

Max. score:

0

Irritation parameter:

edema score

Basis:

animal #2

Time point:

other: overall at 24, 48 and 72 h

Score:

0

Max. score:

0

Irritation parameter:

edema score

Basis:

animal #3

Time point:

other: overall at 24, 48 and 72 h

Score:

0

Max. score:

0

Irritation parameter:

edema score

Max. score:

0

Remarks on result:

other: Max. duration: 0 d: Max. value at end of observation period: 0 (related to all animals)

Irritant / corrosive response data:

No erythema, eschar formation or oedema was observed at the test sites at any of the three rabbits, neither at termination of exposure or at the examinations 1 hour, 24, 48 or 72 hours after termination of exposure.

Other effects:

No systemic effects or other effects were observed throughout the study.

Interpretation of results:

GHS criteria not met

Conclusions:

In conclusion, laccase can be classified as non-irritant to the skin.

Executive summary:

In accordance with OECD guideline 404, a primary skin irritation test in rabbits was performed with laccase, batch PPX 5326.The study was conducted in accordance with GLP.

On the intact skin of the clipped back of each the 3 rabbits, 0.5 mL of the undiluted batch was applied under a patch of gauze (2.5 x 2.5 cm). A semiocclusive bandage was utilised and the adjacent areas of untreated skin served as control.

After 4 hours exposure the patches and the remaining test substance were removed by gentle washing, and the skin reaction, erythema-, eschar- and edema formation was evaluated after ½-1, 24, 48 and 72 hours. None of the rabbits exhibited any dermal reactions at the test side.

 

In conclusion, laccase can be classified as non-irritant to the skin according to the criteria of EU.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Link to relevant study records

Reference

Reference 1

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From June 28, 1996 to October 07, 1996

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to other study

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Version / remarks:

1987.

Deviations:

no

GLP compliance:

yes

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Bred by Novo Nordisk A/S, Denmark
- Weight at study initiation: between 2.7-2.8 kg
- Age at study initiation: 21 wk old adults
- Housing: Individually, in animal room with control of temperature (17-23°C) and humidity (30-70%RH)
- Diet : Standard diet 130 g daily
- Water (e.g. ad libitum): tap water ad libitum
- Acclimation period: 5 days
- Photoperiod (hrs dark / hrs light): 12 hrs/12hrs

IN-LIFE DATES: From: 1996-07-08 To: 1996-07-15

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

Test batch used as is: 0.1 g of 91.7 % TOS (total organic solid), corresponding to 92 mg TOS.

Duration of treatment / exposure:

The test material was applied to the conjunctival sac, no further action done, i.e. no washing.

Observation period (in vivo):

The reactions were judged 1, 24, 48 and 72 hours after instillation of the test material.

Number of animals or in vitro replicates:

3

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing: No
SCORING SYSTEM: The ocular reactions were recorded at 1, 24, 48 and 72 hours after instillation according to the guideline.
TOOL USED TO ASSESS SCORE: Ophtalmoscope. Flourescein was not used as there were no corneal reactions.

Irritation parameter:

conjunctivae score

Remarks:

(redness)

Basis:

animal #1

Time point:

24/48/72 h

Score:

0.3

Max. score:

1

Irritation parameter:

conjunctivae score

Remarks:

(redness)

Basis:

animal #2

Time point:

24/48/72 h

Score:

0.3

Max. score:

1

Irritation parameter:

conjunctivae score

Remarks:

(redness)

Basis:

animal #3

Time point:

24/48/72 h

Score:

0.3

Max. score:

1

Irritation parameter:

chemosis score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

0

Irritation parameter:

chemosis score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0.3

Max. score:

1

Irritation parameter:

chemosis score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

0

Irritation parameter:

cornea opacity score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

0

Irritation parameter:

cornea opacity score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

0

Irritation parameter:

cornea opacity score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

0

Irritation parameter:

iris score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

0

Irritation parameter:

iris score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

0

Irritation parameter:

iris score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

0

Irritant / corrosive response data:

Only slight reactions on conjunctiva were observed after instillation of the freeze-dried powder, batch PPX 5660, with no reactions on cornea or iris. The conjunctival reactions were fully reversible within 48 hours after instillation.

Other effects:

None

Interpretation of results:

GHS criteria not met

Conclusions:

In conclusion, laccase can be classified as a ‘non irritant’ to the rabbit eye.

Executive summary:

In accordance with the OECD guideline 405, a test for eye irritation in rabbits was performed with Laccase, batch PPX 5660.

The eyes of each animal were checked for defects or irritation before instillation and only animals without defects were used.

0.1 g of the freeze-dried Laccase, batch PPX 5660 was placed in the conjunctival sac of the left eye by pulling the lower eyelid away from the eyeball. The lids were gently held together for about one second after instillation. The untreated eye served as control. The ocular reactions were recorded at 1, 24, 48 and 72 hours after instillation according to the specified guideline. Only slight reactions on conjunctiva were observed after instillation of the freeze-dried powder, batch PPX 5660, with no reactions on cornea or iris. The conjunctival reactions were fully reversible within 48 hours after instillation.

In conclusion, laccase can be classified as a ‘non irritant’ to the rabbit eye.

Reference 2

Endpoint:

eye irritation: in vitro / ex vivo

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

an in vitro eye irritation study does not need to be conducted because adequate data from an in vivo eye irritation study are available

Reference 3

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

From January 22, 1996 to March 04, 1996

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to other study

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Version / remarks:

1987.

Deviations:

no

GLP compliance:

yes

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Bred by Novo Nordisk A/S, Denmark
- Weight at study initiation: between 2.4-2.5 kg
- Age at study initiation: 14 wk old adults
- Housing: Individually, in animal room with control of temperature (17-23°C) and humidity (30-70%RH)
- Diet : Standard diet 130 g daily
- Water (e.g. ad libitum): tap water ad libitum
- Acclimation period: 5 days
- Photoperiod (hrs dark / hrs light): 12 hrs/12hrs

IN-LIFE DATES: From: 1996-01-29 To: 1996-02-02

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

Test batch used as is: 0.1 ml of density 1.024 g/ml and 6.6% TOS (total organic solid), corresponding to 6.8 mg TOS.

Duration of treatment / exposure:

The test material was applied to the conjunctivel sac, no further action done, i.e. no washing.

Observation period (in vivo):

The reactions were judged 1, 24, 48 and 72 hours after instillation of the test material.

Number of animals or in vitro replicates:

3

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing: No
SCORING SYSTEM: The ocular reactions were recorded at 1, 24, 48 and 72 hours after instillation according to the guideline.
TOOL USED TO ASSESS SCORE: Ophtalmoscope. Flourescein was not used as there were no corneal reactions.

Irritation parameter:

conjunctivae score

Remarks:

(redness)

Basis:

animal #1

Time point:

other: mean 24, 48 and 72 h

Score:

0

Max. score:

0

Irritation parameter:

conjunctivae score

Remarks:

(redness)

Basis:

animal #2

Time point:

other: mean 24, 48 and 72 h

Score:

0

Max. score:

0

Irritation parameter:

conjunctivae score

Remarks:

(redness)

Basis:

animal #3

Time point:

other: mean 24, 48 and 72 h

Score:

0

Max. score:

0

Irritation parameter:

chemosis score

Basis:

animal #1

Time point:

other: mean 24, 48 and 72 h

Score:

0

Max. score:

0

Irritation parameter:

chemosis score

Basis:

animal #2

Time point:

other: mean 24, 48 and 72 h

Score:

0

Max. score:

0

Irritation parameter:

chemosis score

Basis:

animal #3

Time point:

other: mean 24, 48 and 72 h

Score:

0

Max. score:

0

Irritation parameter:

cornea opacity score

Basis:

animal #1

Time point:

other: mean 24, 48 and 72 h

Score:

0

Max. score:

0

Irritation parameter:

cornea opacity score

Basis:

animal #2

Time point:

other: mean 24, 48 and 72 h

Score:

0

Max. score:

0

Irritation parameter:

cornea opacity score

Basis:

animal #3

Time point:

other: mean 24, 48 and 72 h

Score:

0

Max. score:

0

Irritation parameter:

iris score

Basis:

animal #1

Time point:

other: mean 24, 48 and 72 h

Score:

0

Max. score:

0

Irritation parameter:

iris score

Basis:

animal #2

Time point:

other: mean 24, 48 and 72 h

Score:

0

Max. score:

0

Irritation parameter:

iris score

Basis:

animal #3

Time point:

other: mean 24, 48 and 72 h

Score:

0

Max. score:

0

Irritant / corrosive response data:

No reactions on cornea, iris or conjunctiva were elicited after instillation of the liquid laccase, batch PPX 5326.

Other effects:

None

Interpretation of results:

GHS criteria not met

Conclusions:

In conclusion, laccase can be classified as a ‘non irritant’ to the rabbit eye.

Executive summary:

In accordance with the OECD guideline 405, a test for eye irritation in rabbits was performed with Laccase, batch PPX 5326.

The eyes of each animal were checked for defects or irritation before instillation and only animals without defects were used.

0.1 mL of Laccase, batch PPX 5326 was placed in the conjunctival sac of the left eye by pulling the lower eyelid away from the eyeball. The lids were gently held together for about one second after instillation. The untreated eye served as control. The ocular reactions were recorded at 1, 24, 48 and 72 hours after instillation according to the specified guideline. No reactions on cornea, iris or conjunctiva were elicited after instillation of the liquid batch, PPX 5326.

In conclusion laccase can be classified as a ‘non irritant’ to the rabbit eye.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Additional information

The skin and eye irritation potential of laccase has been tested according to OECD guidelines, and in compliance with GLP. Two studies have been performed on each endpoint, one with the liquid laccase batch and one with the freeze-dried, highly concentrated version of the batch. The only reactions seen were slight redness of conjunctiva in 2 rabbits (max score 1) and slight chemosis in one rabbit (max score 1) in the eye irritation study on the freeze-dried laccase (all totally cleared at 48h), all other readings in both studies were score 0. In the skin irritation studies, slight reversible erythema reactions were noted in 2 rabbits, one of them up to day 3 in the study on the freeze-dried laccase. Max score was 1. The reaction had cleared at the reading on day 6, however, no reading was performed at day 4 and 5, so the reaction might have cleared earlier. All other readings in both skin irritation studies were score 0.

The conclusion was that laccase did not exert any skin and eye irritation. 

Justification for selection of skin irritation / corrosion endpoint:
Key study selected as most relevant study of highest concern.

Justification for selection of eye irritation endpoint:
Key study selected as most relevant study of highest concern.

Justification for classification or non-classification

The skin and eye irritation potential of laccase has been tested according to OECD guidelines, and in compliance with GLP. The conclusion was that laccase did not exert any skin and eye irritation.