Slags, ferrochromium-manufg.

Sensitisation data (human)

Administrative data

Endpoint:

sensitisation data (humans)

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Read-across to stainless steel. Approach supported by the release rates of constituent metals and the surface (passive oxide) characteristics of stainless steel and chromium. Acceptable, well documented study report which meets basic scientific principles.

Data source

Reference

Reference Type:

publication

Title:

Implantation of orthopaedic devices in patients with metal allergy.

Author:

Carlsson, Å. and H. Möller

Year:

1989

Bibliographic source:

Acta Derm Venereol.69: 62-66.

Materials and methods

Type of sensitisation studied:

skin

Study type:

survey

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

18 patients with a contact allergy (chromium, cobalt and/or nickel) were followed up years later after implantation of a metallic orthopaedic device. Clinical and radiographic examinations as well as epicutaneous and intracutaneous tests were carried out to see whether any dermatologic or orthopaedic complications occurred.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

stainless steel

EC Number:

603-108-1

IUPAC Name:

stainless steel

Details on test material:

Implants of stainless steel, containing either chromium and nickel, chromium and cobalt or chromium, nickel and cobalt.
No other data presented on test material.

Method

Type of population:

other: patients

Ethical approval:

not specified

Subjects:

18 patients with contact allergy to metals before bio-implantation of orthopaedic medical devices.

Clinical history:

All subjects had a verified metal allergy before implantation. All patients were allergic to nickel, four to cobalt and nickel and one to Cr and Ni.

Controls:

No

Route of administration:

other: Implantation inside extremities.

Details on study design:

All subjects tested positive for metal allergy before the bio-implantation.
At the the time of follow-up the patients hade been exposed to orthopaedic implants for several years (average 6.3 years).
The patients were examined for dermatologic history and examination, and clinical and radiographic orthopaedic examination. Patch tests were performed with 0.5% potassium dichromate, 0.5% cobalt chloride, and 5% nickel sulphate in petrolatum, using Finn Chambers on Scanpor applied for 48 h and read according to International Contact Dermatitis Research Group (ICDRG) guidelines after a further 24 h. Intracutaneous tests were performed on the forearm with 1 mM metal solutions, and evaluated as tuberculin reaction after 72 h.

Results and discussion

Results of examinations:

No orthopaedic complications were observed, that could be attributed to metal allergy.
One of the 18 patients acquired an eczematous dermatitis after the operation, while three patients saw an eczema disappear. Seven patients had an eczema at about the same degree as before the surgery.
In no cases had an old eczema worsened or a new one appeared.
One of the cases had a skin reaction that could be attributable to a metallic implant. In this case, the eczema did not subside until the implant had been removed.
No new metal allergies were detected in the tests at the follow-up. Three of the patients showed negative results in the follow-up testing. This may be due to false-positive test reactions in the preoperative test, or due to a change in the immunity state.

Applicant's summary and conclusion

Conclusions:

Implantation of stainless steel prostheses did not result in any dermatologic or orthopaedic complications in patients with contact allergy to metals even after many years. Stainless steel can therefore be regarded as safe for orthopaedic implants.

Executive summary:

18 patients with a contact allergy (chromium, cobalt and/or nickel) were followed up years (average 6.3 years) later after implantation of a metallic orthopaedic device. Clinical and radiographic examinations as well as epicutaneous and intracutaneous tests were carried out to see whether any dermatologic or orthopaedic complications occurred. As no complications attributable to metal allergy were observed after exposure during many years, and no new allergies were recognized, it was concluded that stainless steel can be regarded as safe for orthopaedic implants, and the sensitising potential of chromium in alloys can be regarded as very low.