Mill scale (ferrous metal)

Sensitisation data (human)

Administrative data

Endpoint:

sensitisation data (humans)

Type of information:

other: human data

Adequacy of study:

supporting study

Study period:

From October 1991 to January 1992

Reliability:

other: Not rated acc. to Klimisch

Rationale for reliability incl. deficiencies:

other: Any kind of reliability rating is not considered to be applicable, since human studies/reports are not conducted/reported according to standardised guidelines.

Data source

Reference

Reference Type:

publication

Title:

Contact dermatitis and contact sensitization among enamellers and decorators in the ceramics industry

Author:

Motolese, A. et al.

Year:

1993

Bibliographic source:

Contact Dermatitis 28: 59 - 62

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 test used for testing the test substance were applied with Finn Chambers on Scanpor tape to the healthy skin of the back, removed after two days and read one day later. 29 allergens including red iron oxide were tested in 190 workers. Iron oxides were obtained directly from chemical industries supplying ceramic producers. 92 healthy volunteers (cadets of the Military Academy of Modena) were tested with 22 substances which were not included in the standard series at the same concentrations as those used in ceramic workers.

GLP compliance:

not specified

Remarks:

not specified in the publication

Test material

Test material information

1

Reference substance name:

Diiron trioxide

EC Number:

215-168-2

EC Name:

Diiron trioxide

Cas Number:

1309-37-1

Molecular formula:

Fe2O3

IUPAC Name:

diiron trioxide

Test material form:

not specified

Details on test material:

not specified

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source (i.e. manufacturer or supplier) of test material: red iron oxide was obtained directly from chemical industries supplying ceramic producers.

Method

Type of population:

occupational

Ethical approval:

not specified

Subjects:

- Number of subjects exposed: 190 workers (126 enamellers, 64 decorators) from 5 ceramics factories
- Sex: 119 females, 71 males

Clinical history:

not specified

Controls:

92 healthy volunteers (cadets of the Military Academy of Modena) were tested with the test item at the same concentrations as those used in ceramic workers.

Route of administration:

dermal

Details on study design:

TYPE OF TEST(S) USED: patch test (epicutaneous test)

ADMINISTRATION
- Type of application: occlusive
- Description of patch: Finn Chambers (Epitest, Finland) on Scanpor tape (Norgesplaster, Norway)
- Vehicle/solvent: petrolatum
- Concentrations: 2% of test substance
- Testing/scoring schedule: patch tests were applied with Finn Chambers on Scanpor tape to healthy skin of the back for 2 days and skin reactions were read 1 day later (Wilkinson, D. S. et al., 1970).
- Removal of test substance: after 2 days

* Reference: Wilkinson, D. S. et al. (1970): Terminology of contact dermatitis. Acta dermato-venereologica, 50.4, 287-292

Results and discussion

Results of examinations:

NO. OF PERSONS WITH/OUT REACTIONS COMPARED TO STUDY POPULATION
Ceramic workers:
- Number of subjects with positive reactions: 7 (3.7%)
- Number of subjects with negative reactions: 183 (96.3%)
Healthy volunteers:
- Number of healthy subjects with positive reactions: 0
- Number of healthy subjects with negative reactions: 92
- No positive reactions to one or more allergens specific to the ceramics industry were discovered in healthy volunteers.

Applicant's summary and conclusion

Conclusions:

Motolese, A. et al. (1993) investigated the skin sensitising properties of 29 allergens among them red iron oxide in 190 workers (126 enamellers and 64 decorators, 119 females and 71 males) from 5 ceramics factories using occupational test series. The participants were tested with 2% red iron oxide in petrolatum using Finn Chambers on Scanpor tape (patch test) which also contained the remaining 28 allergens to be tested. Furthermore, 2% red iron oxide in petrolatum was tested in 92 healthy volunteers that were not ceramics workers, but cadets of a military academy using the same testing conditions as for workers. The authors observed that 7/190 (3.7%) of the participants showed positive reactions to red iron oxide. In addition, no positive reactions were observed in the healthy volunteers.
The study exhibits methodological deficiencies in the study design and reporting shortcomings. The workers and healthy volunteers were not fully described, since age, medical history about allergy or medication, exposure history and persistence or absence of healthy effects were not specified. Presence of aggravating factors in home and workplace was not specified which makes it impossible to identify any confounding factors that might influence the results. Furthermore, the authors did not consider any other confounding factors such as healthy worker effect or cross-reactivity of nickel, cobalt and iron, which might influence the results of sensitisations. The volume of the test solution was not mentioned, and the reading of skin reactions was done just once at 24 hours after removal of the test substance, but at least two readings are required according to the recommendations of the European Society of Contact Dermatitis guideline. Then, the scoring system was not mentioned, but generally, the scoring criteria recommended by International Contact Dermatitis Research Group (ICDRG) should be used. Positive control and extent of exposure (frequency, magnitude and duration of repeated induction patches followed by challenge patch) were not described. The test substance was obtained directly from the chemical industries supplying ceramic producers and no description of the test item was given (purity and impurities unknown) and therefore it is unclear whether any of the skin reactions were a cause by the test item itself or any impurity.