Palladium monoxide

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

not stated in paper, but submitted for publication in 1974

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Although the study is not conducted to a modern protocol and is somewhat limited, it is nevertheless fairly well documented and scientifically acceptable

Data source

Reference

Reference Type:

publication

Title:

Dermal irritancy of metal compounds. Studies with palladium, platinum, lead, and manganese compounds

Author:

Campbell KI, George EL, Hall LL and Stara JF

Year:

1975

Bibliographic source:

Archives of Environmental Health 30, 168-170

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Dermal irritancy asessed using male albino rabbits using procedures and evaluation criteria adopted from those in use by the National Institute for Occupational Safety and Health, ... a modification of the official Food and Drug Administration procedure [1973]"

GLP compliance:

no

Remarks:

prior to GLP

Test material

Test material information

Constituent 1

Reference substance name:

Palladium monoxide

EC Number:

215-218-3

EC Name:

Palladium monoxide

Cas Number:

1314-08-5

Molecular formula:

OPd

IUPAC Name:

palladium monoxide

Details on test material:

- Name of test material (as cited in study report): Palladium monoxide
- Other: no further details given

Test animals

Species:

rabbit

Strain:

other: albino

Details on test animals or test system and environmental conditions:

no data

Test system

Type of coverage:

occlusive

Preparation of test site:

other: Pairs of test sites, each 2 cm x 2 cm, on the closely clipped dorsolaterals aspects of each animal, one side abraded and the other side intact

Vehicle:

water

Remarks:

0.1 ml

Controls:

yes, concurrent vehicle

Amount / concentration applied:

0.1 g

Duration of treatment / exposure:

24 hours

Observation period:

skin reactions scored immediately on removal of patch and 48 hours later

Number of animals:

Total of 6 rabbits, with up to 7 pairs of test sites each, used to test 14 test substances, some substances tested more than once

Details on study design:

Pairs of test sites, each 2 cm x 2 cm, on the closely clipped dorsolaterals aspects of each animal, one side abraded and the other side intact; Test substances in solid (powder) state were mixed with water (0.1 g quantity mixed with 0.1 ml deionised water) and spread over each site; after application of test substances [several probably tested simultaneously on each animal], test sites occluded; 24 hours later, coverings removed and test sites gently washed with soap, rinsed and dried; skin reactions scored immediately and 48 hours later; evaluation on a grading scale from 0 to 4 [similar to Draize scale]

Results and discussion

In vivo

Results

Irritation parameter:

overall irritation score

Basis:

mean

Remarks:

single test rating or average of two or three

Time point:

other: 24 and 72 hours

Score:

0

Max. score:

4

Reversibility:

not specified

Remarks on result:

no indication of irritation

Irritant / corrosive response data:

Average skin reaction for 24 and 72 hours after the start of treatment calculated for intact and abraded skin. No individual scores or any further information presented in paper, but the data confirm that a score of 0 was obtained for each of the 6 test animals.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Remarks:

evaluation criteria adopted from those in use by the National Institute for Occupational Safety and Health

Conclusions:

Palladium monoxide was not irritant in a limited (pre-GLP) study, involving 24-hr occluded application to the intact and abraded skin of 6 male rabbits.

Executive summary:

In a pre-GLP study, the dermal irritancy of 14 materials, including palladium monoxide, was assessed in albino rabbits. Test materials, mixed with water, were applied to intact and abraded skin of 6 male albino rabbits as 24-hour occluded patches. Coverings were then removed and sites scored immediately and 48 hours later, using a scale from 0 (non-irritant) to 4 (corrosive).

Palladium monoxide failed to give any indication of irritation (score 0) on both intact and abraded skin (mean of reactions at 24 and 72 hours).