Registration Dossier

Administrative data

Endpoint:
sensitisation data (humans)
Type of information:
experimental study
Adequacy of study:
supporting study
Study period:
not reported.
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
study well documented, meets generally accepted scientific principles, acceptable for assessment
Remarks:
Although not sufficient for assessing tin contact sensitivity, the study fulfils it's objectives in studying cross sensitisation.

Data source

Reference
Reference Type:
publication
Title:
Tin: an overlooked contact sensitiser
Author:
Menne T, Andesen KE, Kaaber K, Osmundsen PE, Andersen JR, Yding F & Valeur G
Year:
1987
Bibliographic source:
Contact dermatitis: 16:9-10

Materials and methods

Type of sensitisation studied:
skin
Study type:
study with volunteers
Test guideline
Qualifier:
no guideline available
Principles of method if other than guideline:
Patch tests were performed with metallic tin in 73 nickel-sensitive patients.
GLP compliance:
not specified

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
Tin pure metal coated on to copper discs

Method

Type of population:
general
Ethical approval:
not specified
Subjects:
- Number of subjects exposed: 73
- Sex: Both male and female
- Age: Various ages

No further details reported
Clinical history:
- History of allergy or casuistics for study subject or populations: Nickel sensitivity
Controls:
No data
Route of administration:
dermal
Details on study design:
TYPE OF TEST(S) USED: patch test (epicutaneous test)

ADMINISTRATION
- Type of application: occlusion provided by the solid tin disc.
- Description of patch: A copper disc (12 mm diameter 1 mm thick) plated with pure tin metal was fixed in place on the upper back with Scanpor tape
- Vehicle / solvent: Not applicable
- Testing/scoring schedule: readings were taken at 48, 72 and in some cases 120 hours.
- Removal of disc: After 48 hours of exposure

EXAMINATIONS
- Grading/Scoring system: Reactions were graded by severity.

Results and discussion

Results of examinations:
SYMPTOMS
- Frequency, level, duration of symptoms observed:

NO. OF PERSONS WITH/OUT REACTIONS COMPARED TO STUDY POPULATION
- Number of subjects with positive reactions: 6 with strong positive reactions
- Number of subjects with equivocal reactions 4 doubtful reactions

Any other information on results incl. tables

Table 1: Reactions to tin in 6 nickel-sensitive patients

Age (years)

Sex

History of nickel dermatitis

Hand eczema

Reaction to tin

7

M

+

-

++

23

F

+

-

++

29

F

+

-

+++

30

F

+

-

++

63

M

-

-

++

74

F

+

+

++

EDAX analysis confirmed the surface composition of the tin discs, and the corrosion test established that not even minute amounts of nickel were released after prolonged exposure, 6 of the 73 nickel-sensitive patients had a + + or + + + reaction to the tin discs. The 7-year-old boy was sensitized from metal spectacle frames, 4 patients had a doubtful (? + ) positive reaction and the test was negative in 63 patients. All 73 patients had at least 2 other positive tests at the same time. The patient with the + + + reaction was retested with tin alone 3 months later on the upper arm and again developed a strong positive reaction.

EDAX analysis confirmed the surface composition of the tin discs, and the corrosion test established that not even minute amounts of nickel were released after prolonged exposure, 6 of the 73 nickel-sensitive patients had a + + or + + + reaction to the tin discs. The 7-year-old boy was sensitized from metal spectacle frames, 4 patients had a doubtful (? + ) positive reaction and the test was negative in 63 patients. All 73 patients had at least 2 other positive tests at the same time. The patient with the + + + reaction was retested with tin alone 3 months later on the upper arm and again developed a strong positive reaction.

Applicant's summary and conclusion

Conclusions:
In 73 nickel sensitive patients, 6 strong and 4 doubtful reactions were induced in patients exposed to tin.