Tin zinc oxide (SnZnO3)

Endpoint summary

Description of key information

Skin irritation / corrosion

The test material was determined to be non-irritating and non-corrosive according to Draize. The study assessed the irritancy potential of a test material following a single, 4-hour, semi-occluded application to intact rabbit skin. (OECD Guidelines for Testing of Chemicals 1981, No. 404 "Acute Dermal Irritation/Corrosion" and Annex V Method B4 of EEC Commission Directive 84/449/EEC).

 

Eye irritation

The test material produced a maximum group mean score of 7.3 and was classified as a minimal irritant (Class 3 on a 1 to 8 scale) to the rabbit eye according to a modified Kay and Calandra scoring system. However the reactions seen were not sufficient to warrant classification. The method used followed that described in the OECD Guidelines for Testing of Chemicals (1987) No. 405 "Acute Eye Irritation/Corrosion" referenced as method B5 in Annex V of EEC Commission Directive 84/449/EEC.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

7 March 1989 - 10 March 1989

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Read across to a similar substance. Study conducted to GLP in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not affect the quality of the relevant results.

Justification for type of information:

See read-across justification in Section 13.

Reason / purpose for cross-reference:

other: Target substance

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Accredited breeders; not otherwise specified.
- Age at study initiation: 12 – 20 weeks
- Weight at study initiation: 2.0 – 3.5 kg
- Housing: Individually housed in suspended metal cages.
- Diet (e.g. ad libitum): ad libitum (Preston Farmers Limited, New Leake, Boston, Lincolnshire, UK or suitable alternative)
- Water (e.g. ad libitum): ad libitum tap water from automatic mains.
The diet and water are routinely analyses and are considered not to contain any contaminants that could reasonably be expected to affect the purpose or integrity of the study.
- Acclimation period: Minimum of 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 15 – 21 °C
- Humidity (%): 40 – 75 %
- Air changes (per hr): At least 15
- Photoperiod (hrs dark / hrs light): 12 hours continuous light and 12 hours darkness

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

0.5 g of test material moistened with 0.5 mL of distilled water and applied to 1 intact site of each rabbit.

Duration of treatment / exposure:

4 h

Observation period:

72 h

Number of animals:

3

Details on study design:

PROCEDURE
Method of Application: Test material introduced under gauze patch (2.5 x 2.5 cm) and secured on shorn skin by a strip of surgical adhesive tape (BLENDERM: approximate size 2.5 cm x 4.0 cm). To prevent interference the trunk of each animal wrapped in elasticated corset (TUBIGRIP) for duration of exposure period.
Exposure Period: 4 hours after which dressings removed and application sites decontaminated by cotton wool soaked with water or suitable solvent.

OBSERVATIONS
Skin Evaluation: Scored according to the method of Draize (1959)
Intervals: One hour after removal of patches and approximately 24, 48 and 72 hours later. If no adverse skin reactions at 72 hours, the study is complete. If irritation is persistent, additional observations will be made on days 7 and 14 as necessary to assess reversibility or irreversibility of effects observed.

Irritation parameter:

erythema score

Basis:

mean

Time point:

other: mean of 24, 48 and 72 h

Score:

0

Max. score:

4

Reversibility:

other: no effects seen

Irritation parameter:

edema score

Basis:

mean

Time point:

other: mean of 24, 48 and 72 h

Score:

0

Max. score:

4

Reversibility:

other: no effects seen

Irritant / corrosive response data:

Corrosive effects noted in 0 animals, test material therefore classified as non-corrosive

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Non-irritant

Executive summary:

The test material was determined to be non-irritating and non-corrosive according to Draize. The study assessed the irritancy potential of a test material following a single, 4-hour, semi-occluded application to intact rabbit skin. (OECD Guidelines for Testing of Chemicals 1981, No. 404 "Acute Dermal Irritation/Corrosion" and Annex V Method B4 of EEC Commission Directive 84/449/EEC).

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Link to relevant study records

Reference

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

13 March 1989 - 17 March 1989

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Read across to similar substance. Study conducted to GLP in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not affect the quality of the relevant results.

Justification for type of information:

See read-across justification in Section 13.

Reason / purpose for cross-reference:

other: Target substance

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.5 (Acute Toxicity: Eye Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: David Percival Ltd., Moston, Sandbach, Cheshire, U.K
- Age at study initiation: 12 – 16 weeks
- Weight at study initiation: 2.59 – 2.94kg
- Housing: The animals were individually housed in suspended metal cages.
- Diet (e.g. ad libitum): ad libitum. Free access to food (Rabbit Diet, Preston Farmers Limited, New Leake, Boston, Lincolnshire, U.K.) was allowed throughout the study.
- Water (e.g. ad libitum): Free access to mains drinking water was allowed throughout the study.
- Acclimation period: minimum 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 14 - 18°C
- Humidity (%):60 - 65% relative
- Air changes (per hr): approximately 15
- Photoperiod (hrs dark / hrs light): give 12 hours continuous light and 12 hours darkness

Vehicle:

unchanged (no vehicle)

Controls:

other: The left eye remained untreated and was used for control purposes.

Amount / concentration applied:

The test material (100 mg) was placed into the right eye of each rabbit by gently pulling the lower lid away from the eyeball to form a cup into which the test material was dropped. The upper and lower eyelids were held
together for about one second immediately after application, to prevent loss of the test material, and then released.

Observation period (in vivo):

72 h

Number of animals or in vitro replicates:

3

Details on study design:

For the purpose of this study the test material was used as supplied.
The identification and stability of the test material were not determined.

Procedure
Immediately before commencement of the test, both eyes of the three provisionally selected test rabbits were examined for evidence of ocular irritation or defect using the light source from a standard ophthalmoscope. Animals showing evidence of ocular lesions were rejected and replaced.

On the day of the test each animal was held firmly but gently until quiet. The test material (100 mg) was placed into the right eye of each rabbit by gently pulling the lower lid away from the eyeball to form a cup into which the test material was dropped. The upper and lower eyelids were held together for about one second immediately after application, to prevent loss of the test material, and then released. The left eye remained untreated and was used for control purposes.

The initial pain reaction was assessed for each animal, immediately after dosing, according to a six point scale.
Assessment of damage/irritation was made 1, 24, 48 and 72 hours following treatment, according to the numerical evaluation developed by Draize J.H. 1959, Association of Food and Drug Officials of the United States, Austin, Texas, "The Appraisal of the Safety of Chemicals in Foods, Drugs and Cosmetics"). Examination of the eye was facilitated by use of the light source from a standard ophthalmoscope.

No evidence of ocular irritation was noted at the 72-hour observation and the study was terminated.

Interpretation of Results
The numerical values corresponding to each animal, tissue and observation time were recorded. The data relating to the conjunctivae were designated by the letters A (redness), B (chemosis) and C (discharge), those relating to the iris designated by the letter D and those relating to the cornea by the letters E (degree of opacity) and F (area of opacity). For each tissue the total score was calculated as follows:

Total score for conjunctivae = (A + B + C) x 2
Total score for iris = D x 5
Total score for cornea = (E x F) x 5

Using the numerical data obtained a modified version of the system described by Kay J.H. and Calandra J.C., J. Soc. Cosmet. Chem., 1962 13 281 - 289 was used to classify the ocular irritancy potential of the test material. This was achieved by adding together the total scores for the cornea, iris and conjunctivae for each of the 1, 24, 48 and 72-hour observations for each rabbit. The group means of the total scores for each observation were calculated. The highest of these group means (the maximum mean score) together with the persistence of the reactions enabled classification of the eye irritancy potential of the test material.

Irritation parameter:

cornea opacity score

Basis:

mean

Time point:

other: Mean overall score for 24, 48 and 72 h

Score:

0

Max. score:

4

Reversibility:

other: not applicable

Irritation parameter:

iris score

Basis:

mean

Time point:

other: Mean overall score for 24, 48 and 72 h

Score:

0

Max. score:

2

Reversibility:

other: not applicable

Irritation parameter:

conjunctivae score

Remarks:

Redness

Basis:

mean

Time point:

other: Mean overall score for 24, 48 and 72 h

Score:

0.34

Max. score:

3

Reversibility:

fully reversible within: 48 h

Irritation parameter:

chemosis score

Basis:

mean

Time point:

other: Mean overall score for 24, 48 and 72 h

Score:

0.11

Max. score:

4

Reversibility:

fully reversible within: 48 h

Irritation parameter:

conjunctivae score

Remarks:

Discharge

Basis:

mean

Time point:

other: Mean overall score for 24, 48 ad 72 h

Score:

0

Max. score:

3

Reversibility:

other: not applicable

Irritant / corrosive response data:

Slight to moderate initial pain was noted following treatment. No adverse corneal or iridial effects were noted.

Moderate conjunctival irritation was noted in two treated eyes one hour after treatment. Minimal conjunctival irritation was noted in one treated eye at this time and in all treated eyes at the 24-hour observation.

All treated eyes appeared normal at the 48-hour observation.

 Individual Scores and Individual Total Scores for Ocular Irritation

Rabbit Number and Sex	25 Male (IPR = 2)				102 Female (IPR = 3)				89 Female (IPR = 2)
Time After Treatment	1 h	24 h	48 h	72 h	1 h	24 h	48 h	72 h	1 h	24 h	48 h	72 h
CORNEA E = Degree of opacity F = area of opacity	0 0	0 0	0 0	0 0	0 0	0 0	0 0	0 0	0 0	0 0	0 0	0 0
Score (E x F) x 5	0	0	0	0	0	0	0	0	0	0	0	0
IRIS D	0	0	0	0	0	0	0	0	0	0	0	0
Score (D x 5)	0	0	0	0	0	0	0	0	0	0	0	0
CONJUNCTIVAE A = Redness B = Chemosis C = Discharge	2 1 0	1 0 0	0 0 0	0 0 0	2 1 1	1 1 0	0 0 0	0 0 0	2 1 1	1 0 0	0 0 0	0 0 0
Score (A + B + C) x 2	6	2	0	0	8	4	0	0	8	2	0	0
Total Scores	6	2	0	0	8	4	0	0	8	2	0	0

Key: h = hour(s)

IPR = initial pain reaction        

                                                                                      

Individual Total Scores and Group Mean Scores for Ocular Irritation

Rabbit Number and Sex	Individual Total Scores at:
	1 hour	24 hours	48 hours	72 hours
25 Male 102 Female 89 Female	6 8 8	2 4 2	0 0 0	0 0 0
Group Total	22	8	0	0
Group Mean Scores	7.3	2.7	0.0	0.0

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The test material produced a maximum group mean score of 7.3 and was classified as a minimal irritant (Class 3 on a 1 to 8 scale) to the rabbit eye according to a modified Kay and Calandra scoring system. However the reactions seen were not sufficient to warrant classification.

Executive summary:

The test material produced a maximum group mean score of 7.3 and was classified as a minimal irritant (Class 3 on a 1 to 8 scale) to the rabbit eye according to a modified Kay and Calandra scoring system. However the reactions seen were not sufficient to warrant classification. The method used followed that described in the OECD Guidelines for Testing of Chemicals (1987) No. 405 "Acute Eye Irritation/Corrosion" referenced as method B5 in Annex V of EEC Commission Directive 84/449/EEC.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Justification for selection of skin irritation / corrosion endpoint:
The key study was conducted in accordance with GLP and the standardised guidelines OECD Guidelines for Testing of Chemicals 1981, No. 404 "Acute Dermal Irritation/Corrosion" and Annex V Method B4 of EEC Commission Directive 84/449/EEC. It was awarded a reliability score of 2 in accordance with the principles of Klimisch (1997) due to the fact that the study is being used in a read-across capacity. The test was conducted on the analogous substance Zinc Hydroxystannate. The results are considered to be representative of the registered material.

Justification for selection of eye irritation endpoint:
The key study was conducted in accordance with GLP and the standardised guidelines OECD Guidelines for Testing of Chemicals (1987) No. 405 "Acute Eye Irritation/Corrosion" referenced as method B5 in Annex V of EEC Commission Directive 84/449/EEC. It was awarded a reliability score of 2 in accordance with the principles of Klimisch (1997) due to the fact that the study is being used in a read-across capacity. The test was conducted on the analogous substance Zinc Hydroxystannate. The results are considered to be representative of the registered material.

Justification for classification or non-classification

Skin Irritation/Corrosion

The test material was determined to be non-irritating and non-corrosive according to the Draize scale. In accordance with Annex I, Regulation 1272/2008, the test material does not require classification as it does not meet the criteria.

Eye Irritation

The test material produced a maximum group mean score of 7.3 and was described as a minimal irritant (Class 3 on a 1 to 8 scale) to the rabbit eye according to a modified Kay and Calandra scoring system. However the reactions seen were not sufficient to warrant classification in accordance with Annex I, Regulation 1272/2008.