title: Exposure to refractory ceramic fibres in the metal industry.
abstract: Refractory ceramic fibres (RCF) are used in thermal isolation in the metal industry where high temperatures are regularly employed. Asbestos materials were earlier commonly used for these purposes. In this work, two Finnish steel plants, three foundries and a repair shop were studied for the ceramic fibre exposure of their workers under normal production and during the replacement of oven insulation. Personal and stationary sampling was used together with a novel nasal lavage sampling for the evaluation of personal exposure. Fibres were counted with optical and electron microscopy and they were identified using an energy-dispersive X-ray analyser. Ceramic fibres were found in most production phases [range <0.01-0.29 fibres per cubic centimetre (f cm(-3))]. Considerably higher fibre counts were obtained during the maintenance work (range <0.01-14.2 f cm(-3)). Nasal sampling was found to correlate with the airborne fibre concentrations at the group level. The mean fibre concentrations varied from 34 to 6680 f ml(-1) of lavage liquid. Use of personal respiratory protectors diminished the exposure on the average as analysed in the lavage specimens, but the effect of respirator use did not appear clearly in the results. Because of the heat conditions, the workers used the respirators for a strict minimum period. A considerable exposure to RCF occurs in the studied plants. Its risk should be evaluated and managed more closely in view that the material is carcinogenic. Use of personal respiratory protectors should be encouraged. Their effective use could be verified by the nasal sampling for fibres after the work shift.
authors.affiliation: Finnish Institute of Occupational Health, P.O. Box 93, FI-70701 Kuopio, Finland. markku.linnainmaa@ttl.fi
authors.forename: Markku
authors.initials: M
authors.lastname: Linnainmaa
authors.forename: Juhani
authors.initials: J
authors.lastname: Kangas
authors.forename: Milja
authors.initials: M
authors.lastname: Mäkinen
authors.forename: Sirpa
authors.initials: S
authors.lastname: Metsärinne
authors.forename: Antti
authors.initials: A
authors.lastname: Tossavainen
authors.forename: Jaakko
authors.initials: J
authors.lastname: Säntti
authors.forename: Marika
authors.initials: M
authors.lastname: Veteli
authors.forename: Heikki
authors.initials: H
authors.lastname: Savolainen
authors.forename: Pentti
authors.initials: P
authors.lastname: Kalliokoski
mesh_terms: D000395:Air Pollutants, Occupational / Q000032:analysis / Q000633:toxicity*; D002516:Ceramics / Q000032:analysis / Q000633:toxicity*; D004391:Dust / Q000032:analysis; D005387:Finland; D006801:Humans; D019570:Inhalation Exposure / Q000009:adverse effects / Q000032:analysis; D008669:Metallurgy; D008855:Microscopy, Electron, Scanning / Q000379:methods; D019016:Mineral Fibers / Q000032:analysis / Q000633:toxicity; D017817:Nasal Lavage Fluid / Q000737:chemistry; D016273:Occupational Exposure / Q000009:adverse effects* / Q000032:analysis; D013232:Steel
chemical_list: D000395:Air Pollutants, Occupational; D004391:Dust; D019016:Mineral Fibers; D013232:Steel