Diammonium hexachloropalladate

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

30 August 1989 – 6 September 1989

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP study conducted according to a company standard protocol designed to comply with the recommendations of OECD guideline No. 404

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1989

Report date:

1989

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Reference substance 001

Cas Number:

19168-23-1

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

- Name of test material (as cited in study report): ammonium hexachloropalladate (IV)
- Substance type: red-coloured powder
- Physical state: solid
- Lot/batch No.: 042011
- Storage condition of test material: room temperature

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: David Percival Ltd, Moston, Sandbach, Cheshire, UK
- Age at study initiation: approx. 12-16 weeks
- Weight at study initiation: 2.68-2.96 kg
- Housing: individually in suspended metal cages
- Diet: ad libitum Rabbit Diet supplied by Preston Farmers Limited, New Leake, Boston, Lincolnshire, UK
- Water: ad libitum
- Acclimation period: minimum of 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 16-20
- Humidity (%): 60-70
- Air changes (per hr): approx. 15/hr
- Photoperiod (hrs dark / hrs light): 12 hours light and 12 hours dark

Test system

Type of coverage:

semiocclusive

Preparation of test site:

other: test site clipped free of fur, described as “shorn skin”

Vehicle:

water

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit):0.5 g moistened with 0.5 ml distilled water

VEHICLE
- Amount(s) applied (volume or weight with unit): 0.5 ml
- Purity: distilled

Duration of treatment / exposure:

4 hrs

Observation period:

Approximately 1, 24, 48 and 72 hrs after removal of the patch

Number of animals:

One female and two males

Details on study design:

TEST SITE
- Area of exposure: 2.5 cm2
- Type of wrap if used: A gauze patch secured with a strip of surgical adhesive tape (BLENDERM, approx 2.5 x 4.0 cm) and an elasticated corset (TUBIGRIP) wrapped around the trunk.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): residual test material removed by gentle swabbing with cotton wool soaked in diethyl ether
- Time after start of exposure: 4 hrs

SCORING SYSTEM: The test sites were examined for evidence of primary irritation approximately 1 hr following removal of the patch and 24, 48 and 72 hrs later and scored according to the method of Draize (1959). An additional observation was made on day 7. The scores for erythema (and eschar) formation and oedema formation at the 24 and 72 hr observation times were totalled for the three rabbits (12 values) and divided by 6 to give the primary irritation index. This was then used to classify the skin irritation properties of the test material according to:

Primary Irritation Index Classification
0 Non-irritant
>0 – 2 Mild irritant
>2 – 5 Moderate irritant
>5 – 8 Severe irritant

The results were also interpreted according to EEC Directive 83/467/EEC adapting Council Directive 67/548/EEC on the regulations relating to the classification, packaging and labelling of dangerous substances.

Results and discussion

In vivo

Results

Irritation parameter:

primary dermal irritation index (PDII)

Basis:

mean

Time point:

other: 24 and 72 hrs after removal of the patch

Score:

3.5

Max. score:

8

Reversibility:

fully reversible within: 7 days

Remarks on result:

other: Well-defined erythema with very slight or slight oedema was noted at all treated skin sites one hour after patch removal and at subsequent 24, 48 and 72-hr observations

Other effects:

Depilated glossy skin was noted at all treated skin sites and at all observations times and persisted to the 7 day observation time. Reduced re-growth of fur and desquamation were also noted at the 7 day observation period.

Applicant's summary and conclusion

Interpretation of results:

Category 2 (irritant)

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

In a GLP skin irritation study in rabbits, equivalent to guideline (OECD TG 404), undiluted diammonium hexachloropalladate produced moderate skin irritation.

Executive summary:

In a GLP skin irritation study in rabbits, equivalent to guideline (OECD TG 404), neat diammonium hexachloropalladate (0.5 g) was applied (semi-occluded) to the clipped, intact skin of three rabbits. After 4 hrs, the patches were removed and, approximately 1 hr later, the skin sites assessed for erythema (and eschar) formation and oedema formation. These sites were again assessed 24, 48 and 72 hrs, and 7 days later.

The sums of the 24- and 72-hr values were combined and divided by six to give a primary irritation score of 3.5 (of 8). Ammonium hexachloropalladate (IV) was therefore considered as a moderate skin irritant in this test system. No corrosive effects were noted. Although the skin irritation was reversible within the 7-day observation period, depilated glossy skin persisted for the 7 days, and desquamation and reduced re-growth of fur was also noted at 7 days. As such, it would be precautionary to classify as a skin irritant (Category 2), according to CLP criteria (EC 1272/2008).