Zinc methacrylate

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

22 May - 10 June 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

No justification could be found in the records.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

no

Principles of method if other than guideline:

Not applicable

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Zinc methacrylate

EC Number:

236-144-8

EC Name:

Zinc methacrylate

Cas Number:

13189-00-9

Molecular formula:

C4H6O2.1/2Zn

IUPAC Name:

zinc methacrylate

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

- Name of test material (as cited in study report): Zinc Dimethacrylate
- Physical state: White powder
- Analytical purity: 95.3 %
- Lot/batch No.: 1107289741
- Date of receipt: 10 April 2012
- Expiration date of the lot/batch: 31 October 2012
- Storage condition of test material: Room temperature in the dark over silica gel

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Harlan Laboratories UK Ltd., Leicestershire, UK.
- Age at study initiation: 12-20 weeks
- Weight at study initiation: 2.59-2.64 kg
- Housing: Animals were individually housed in suspended cages.
- Diet: Food (2930C Teklad Global Rabbit diet supplied by Harlan Laboratories UK Ltd., Oxon, UK), ad libitum
- Water: Mains drinking water, ad libitum
- Acclimation period: 5 days

ENVIRONMENTAL CONDITIONS
- Temperature: 17-23 °C
- Humidity: 30-70 %
- Air changes: 15 changes/h
- Photoperiod: 12 h dark / 12 h light

Test system

Type of coverage:

semiocclusive

Preparation of test site:

other: clipped

Vehicle:

other: 0.5 g of the test item, moistened sufficiently with 0.5 ml of distilled water to achieve paste consistency

Controls:

not required

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (weight with unit): 0.5 g

Duration of treatment / exposure:

4 h

Observation period:

7 days for first animal and 72 h for remaining two animals.

Number of animals:

3 males

Details on study design:

TEST SITE
- Area of exposure: Dorsal/flank area
- Type of wrap if used: Test item was applied to the skin under a 2.5 cm x 2.5 cm cotton gauze patch. The patch was secured in position with a strip of surgical adhesive tape. To prevent the animal interfering with the patch, the trunk of the rabbit was wrapped in an elasticated corset and the animal was returned to its cage for the duration of the 4 hour exposure period.

REMOVAL OF TEST SUBSTANCE
- After removal of the dressing, any residual test item removed by gentle swabbing with cotton wool soaked in distilled water.
- Time after start of exposure: 4 h

SCORING SYSTEM: According to OECD Guideline 404

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal #1

Remarks:

mean individual score

Time point:

24/48/72 h

Score:

ca. 2

Max. score:

4

Reversibility:

fully reversible within: 7 days

Results 2

Irritation parameter:

edema score

Basis:

animal #1

Remarks:

mean individual score

Time point:

24/48/72 h

Score:

ca. 1.3

Max. score:

4

Reversibility:

fully reversible within: 7 days

Results 3

Irritation parameter:

erythema score

Basis:

animal #2

Remarks:

mean individual score

Time point:

24/48/72 h

Score:

ca. 0

Max. score:

4

Reversibility:

other: not applicable

Results 4

Irritation parameter:

edema score

Basis:

animal #2

Remarks:

mean individual score

Time point:

24/48/72 h

Score:

ca. 0

Max. score:

4

Reversibility:

other: not applicable

Results 5

Irritation parameter:

erythema score

Basis:

animal #3

Remarks:

mean individual score

Time point:

24/48/72 h

Score:

ca. 0

Max. score:

4

Reversibility:

other: not applicable

Results 6

Irritation parameter:

edema score

Basis:

animal #3

Remarks:

mean individual score

Time point:

24/48/72 h

Score:

ca. 0

Max. score:

4

Reversibility:

other: not applicable

Irritant / corrosive response data:

- Very slight erythema and very slight oedema were noted at one treated skin site immediately after patch removal with well-defined erythema and slight oedema noted at 1 and 24 h after patch removal. Well-defined erythema and very slight oedema were noted at this treated skin site at the 48 and 72 h observations. Light brown discolouration of the epidermis and loss of skin elasticity were noted at this treated skin site at the 24, 48 and 72 h observations with slight desquamation noted at the 7-Day observation.
- No evidence of skin irritation was noted at two treated skin sites during the study.

Other effects:

All animals showed expected bodyweight gain during the study.

Any other information on results incl. tables

Table 7.3.1/1: Individual Skin Reactions

Skin Reaction	Observation Time (following patch removal)	Individual Scores – Rabbit Number and Sex
		72042 Male	72101 Male	72102 Male
Erythema/Eschar Formation	Immediately	1	0	0
	1 h	2	0	0
	24 h	2 BrLe	0	0
	48 h	2 BrLe	0	0
	72 h	2 BrLe	0	0
	7 days	0D	-	-
	Mean (24, 48 and 72 h)	2	0	0
Oedema Formation	Immediately	1	0	0
	1 h	2	0	0
	24 h	2	0	0
	48 h	1	0	0
	72 h	1	0	0
	7 days	0	-	-
	Mean (24, 48 and 72 h)	1.3	0	0

Br = Light brown discolouration of the epidermis

Le = Loss of skin elasticity

D = Slight desquamation

- = Not applicable

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

Under the test conditions, Zinc Dimethacrylate is not classified as irritating to skin.

Executive summary:

In a primary dermal irritation study performed according to OECD Guideline 404 and in compliance with GLP, three male New Zealand White rabbits were dermally exposed to 0.5 g of Zinc Dimethacrylate under a semi-occlusive dressing. The test item was first evaluated on a single animal and the duration of exposure was 4 h on the dorsal/flank area. After consideration of the skin reactions produced in the first animal, two additional animals were similarly treated. After removal of the residual test item, irritation was scored as outlined in the OECD Guideline 404 at 1, 24, 48 and 72 h and 7 days after exposure. Very slight erythema and very slight oedema were noted at one treated skin site immediately after patch removal with well-defined erythema and slight oedema noted at 1 and 24 h after patch removal. Well-defined erythema and very slight oedema were noted at this treated skin site at the 48 and 72 h observations. Light brown discolouration of the epidermis and loss of skin elasticity were noted at this treated skin site at the 24, 48 and 72 h observations with slight desquamation noted at the 7-Day observation. No evidence of skin irritation was noted at two treated skin sites during the study. Mean individual scores at 24, 48 and 72 h after exposure for the 3 animals were 2, 0, 0 for erythema and 1.3, 0, 0 for oedema score, respectively. In this study, Zinc Dimethacrylate is not a skin irritant on male rabbits. Under the test conditions, Zinc Dimethacrylate was not classified as irritating to skin (Bradshaw, 2012).