Registration Dossier

Administrative data

Endpoint:
sensitisation data (humans)
Type of information:
experimental study
Adequacy of study:
supporting study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Published paper, limited reporting. Data appear scientifically acceptable

Data source

Reference
Reference Type:
publication
Title:
Allergy to palladium
Author:
Rebandel P and Rudzki E
Year:
1990
Bibliographic source:
Contact Dermatitis 23, 121-122

Materials and methods

Type of sensitisation studied:
skin
Study type:
study with volunteers
Principles of method if other than guideline:
Patch testing of patients with allergic contact dermatitis

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Test material form:
not specified
Details on test material:
- Name of test material (as cited in study report): Tetramine palladium nitrate
- Impurities (identity and concentrations): Atomic absorption spectrometry showed less than 0.2 mg nickel per litre (i.e. 0.2 ppm) [the paper erroneously states this to be 0.2%. However, 0.2 mg per litre = 200 mg per 1000 litre, i.e. 0.2 g per 1000 litre = 0.2 ppm; 0.2 mg per litre = 0.02 mg per 100 ml = 0.00002 g per 100 ml = 0.00002%, not 0.2%]

Method

Type of population:
general
Controls:
Not applicable
Route of administration:
dermal
Details on study design:
100 consecutive patients with contact dermatitis were patch tested with 1% palladium (II) chloride and from 1% to 0.001% tetramine palladium nitrate in water, at the Department of Dermatology, Warsaw School of Medicine, Poland. No details on patch tests are presented in the paper, but probably involved 24/48-hour covered contact.

Results and discussion

Results of examinations:
None of the 90 nickel-negative patients reacted to 1% palladium chloride or 1% tetramine palladium nitrate (this group contained 4 patients positive to chromate, 2 positive to chromate and cobalt, and 1% to 0.1% mercuric chloride).

Ten patients (all women) were responsive to both nickel and the palladium compounds at 1%. Eight of these patients were tested with several concentrations of both nickel and tetramine palladium nitrate. The lowest palladium concentrations causing a reaction was 0.5% (nickel content 0.001%) in four of these patients and 1.0% (nickel content 0.002%) in the remaining four. Seven of these eight patients failed to react when patch tested with nickel concentrations higher (0.01 to 1.0%) than the nickel concentrations in the lowest palladium concentrations giving a positive reaction. The remaining patient was positive to the lowest concentration of nickel tested (0.01%) and thus it was not possible to determine the lowest nickel concentration to which she would react; she gave a positive reaction to 0.5% tetramine palladium nitrate (nickel content 0.001%).

Nine of the ten patients reacting to tetamine palladium nitrate had no known previous exposure to palladium.

Applicant's summary and conclusion

Conclusions:
Patch testing of 100 contact dermatitis patients with 0.001 - 1% aqueous tetraamminepalladium (II) nitrate revealed ten (all women) who were responsive to both nickel and the palladium compound.
Executive summary:

Patch testing [probably 24/48 -hour covered contact] of 100 consecutive contact dermatitis patients attending a dermatology clinic in Poland with 1% aqueous tetraaminepalladium (II) nitrate or 1% aqueous palladium (II) chloride revealed ten (all women) who were responsive to both nickel and the palladium compounds. Eight of these were patch tested with 0.001 - 1% tetraamminepalladium (II) nitrate. Seven gave a reaction to a palladium compound concentration (0.5% or 1.0%) with a nickel concentration (0.001% or 0.002%) below the highest nickel concentration not causing a reaction in these patients. One patient who reacted to 0.5% tetraamminepalladium (II) nitrate (nickel content 0.001%) was positive to the lowest nickel concentration tested (0.01%) and it was thus not possible to determine the lowest nickel concentration to which she would react. Nine of the ten patients had no known previous exposure to palladium.