Disilver oxide

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1989-02-21 to 1989-02-24

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Guideline study. At the time of the study conduct, GLP was not compulsory. However, the study was conducted in accordance with the principles of GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1989

Report date:

1989

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Disilver oxide

EC Number:

243-957-1

EC Name:

Disilver oxide

Cas Number:

20667-12-3

Molecular formula:

Ag2O

IUPAC Name:

silver(1+) oxide

Details on test material:

- Name of test material (as cited in study report): silver(I)-oxide
- Physical state: brown-grey powder
- Stability under test conditions: Not indicated by the sponsor.
- Storage condition of test material: st room temperature

Test animals

Species:

rabbit

Strain:

other: white russian (albino)

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: ASTA Pharma AG, Bielefeld
- Age at study initiation: 9 months (males) and 11 months (females)
- Weight at study initiation: 2.6 kg (males); 2.7 and 3.2 kg (females)
- Housing: stainless steel cages with grating floor, type ASTA, size: 48.5x40x36.5 cm (LxBxH), individually housing
- Diet: approx. 120 g/day x animal (Standard diet, ssniff K, "Special Diet for Rabbits" supplied by ssniff Spezialfutter GmbH, D-4770 Soest)
- Water: ad libitum
- Acclimation period: 1 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 - 22
- Humidity (%): 45 - 60
- Photoperiod: 12 hours dark/light

Test system

Type of coverage:

occlusive

Preparation of test site:

shaved

Vehicle:

water

Controls:

other: The opposite area of the treated dorsal skin was used as control site (no test material application).

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 g of the test substance were moistened with demineralised water and placed on the shorn dorsal skin.

VEHICLE
- Amount(s) applied (volume or weight with unit): 0.35 mL

Duration of treatment / exposure:

4 hours

Observation period:

1, 24, 48 and 72 hours after removal of the patches

Number of animals:

3 rabbits (1 male and 2 females)

Details on study design:

TEST SITE
- Area of exposure: The test material was placed on the shorn dorsal skin area between shoulder and sacrum.
- Type of wrap if used: The site of application was covered with a linen cloth (approx. 6.25 cm2) which adhered to a synthetic film glue. A bandage wrapped several times around the trunk (Acrylastic, No. 2408, width 8 cm; P. Beiersdorf and Co. AG, Hamburg) provided a complete occlusion.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): After the end of the exposition time remaining test material was gently washed off as far as possible.

SCORING SYSTEM: The treated skin area was qualitatively (erythema/ eschar resp. edema) and quantitatively (values 0-4) assessed using the DRAIZE method. In addition, attention was paid to the occurrence of further reactions on the skin (e.g. corrosive effect) and to clinical symptoms (systemic toxic effects).

EVALUATION: The evaluation of the cutaneous irritation effect at observation times 1, 24, 48 and 72 hours p. appl. was expressed by an irritation index. A corresponding gradation was allocated to this index by the following scheme in a modified method according to Gilman et al. (1983):
0 - 0.5 = non irritant
0.6 - 3.0 = slightly irritant
3.1 - 5.0 = moderately irritant
5.1 - 8.0 = severly irritant

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:

not specified

Results 2

Irritation parameter:

edema score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

not specified

Irritant / corrosive response data:

The single application of 0.5 gram silver(I)-oxide to the intact skins of 3 rabbits caused no changes. During the observation period neither erythema nor edema could be detected.

Other effects:

The treated skin area was yellow to brown discoloured 24 hours after removal of the patch until the end of the 14-day observation period.
Systemic-toxic effects did not occur after dermal application of the test substance. The general condition of the test animals was not affected.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Remarks:

Silver(I)-oxide is not irritant to the skin

Conclusions:

The irritation index is 0.0.
Silver(I)-oxide therefore is a non-irritant in this test system.