Potassium sulphite

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

Minor deviations with no effect on the results: - Purity and stability were not stated. - According to guideline, the observations should be made at 30-60 minutes and at 24, 48, and 72 hours after patch removal and not 24 hours, 48 hours and 72 days after start of exposure. - A modified Draize scoring system was used in this study. - According to the guideline the test substance should be moistened with water. In this study the test patch was moistend with water for application instead of the test substance. - The water supply was not unrestricted. - in the study report it was stated that observations were made at 30-60 minutes after patch removal. In the result table data were listed for an observation at 4-hours.

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)

Version / remarks:

1981-05-12

Deviations:

yes

Remarks:

, see "rationale for reliability"

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Potassium sulphite

EC Number:

233-321-1

EC Name:

Potassium sulphite

Cas Number:

10117-38-1

Molecular formula:

K2SO3

IUPAC Name:

potassium sulphite

Test material form:

not specified

Details on test material:

- Name of test material (as cited in study report): Potassium sulphite

Specific details on test material used for the study:

not specified

Test animals

Species:

rabbit

Strain:

Vienna White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Savo; Med. Versuchstierzuchten GmbH; 7964 Kisslegg/Allgäu FRG
- Weight at study initiation: mean weight 2.56 kg (Individual weights of the three test animals:2.78 kg, 2.22 kg, and 2.68 kg)
- Housing: The animals were individually housed. The animals were housed in fully air-conditioned rooms. Cage made of stainless steel with wire mesh walk floors. Floor area: 40 cm X 51 cm. No bedding in the cages.Sawdust in the waste trays.
- Diet: Kliba 341, 4 MM; Firma Klingentalmuehle AG, CH- 4303 Kaiseraugst, Switzerland (about 130 g per animal per day)
- Water: About 250 ml tap water per animal per day
- Acclimation period: At least 8 days before the beginning of the study; same housing conditions as during the study.

ENVIRONMENTAL CONDITIONS
- Temperature: 20 - 24 °C
- Relative humidity: 30 - 70 %
- Photoperiod (hrs dark / hrs light): 12/12

Test system

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

water

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): A dose of 0.5 g of the unchanged test substance.

Duration of treatment / exposure:

4 hours

Observation period:

72 hours; Readings of skin irritation at 30 - 60 minutes after removal of the test patches and 24 h, 48 h and 72 h after the beginning of application.

Number of animals:

3 male rabbits

Details on study design:

TEST SITE
The fur of the rabbits was clipped at least 15 hours before the beginning of the study.The application area was 2.5 cm X 2.5 cm on the upper third of the back or flanks. The test patch (2.5 cm X 2.5 cm) was covered with a dose of 0.5 g of the unchanged test substance and has been moistened with aqua dest.. Test patches were secured in position with a porous dressing (four layers of absorbant gauze and porous bandage). The untreated skin sites of the same animals was used as negative control.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): The test substance was removed with lutrol and lutrol/water (1:1).
- Time after start of exposure: At the end of the exposure period

SCORING SYSTEM: Modified Draize scoring system
Evaluation of erythema (R) and oedema (ED):
0 = none
1 = very slight
2 = well-defined
3 = moderate to severe
4 = severe to very severe

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

mean

Remarks:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

other: The readings were made 24 h, 48 h and 72 h after the beginning of application

Results 2

Irritation parameter:

edema score

Basis:

mean

Remarks:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

other: The readings were made 24 h, 48 h and 72 h after the beginning of application

Results 3

Irritation parameter:

erythema score

Basis:

mean

Remarks:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

other: The readings were made 24 h, 48 h and 72 h after the beginning of application

Results 4

Irritation parameter:

edema score

Basis:

mean

Remarks:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

other: The readings were made 24 h, 48 h and 72 h after the beginning of application

Results 5

Irritation parameter:

erythema score

Basis:

mean

Remarks:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

other: The readings were made 24 h, 48 h and 72 h after the beginning of application

Results 6

Irritation parameter:

edema score

Basis:

mean

Remarks:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritant / corrosive response data:

Very slight erythema was observed in two animals at the 4-hour reading, which had disappeared at the 24 hour reading.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The substance is not irritating to the skin based on an in vivo study (OECD 404).
According to the EC Regulation No. 1272/2008 and subsequent regulations, the test item is not classified as skin irritant.