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Document ID (ISN)112143
CIS number 11-0797
ISSN - Serial title 1545-9624 - Journal of Occupational and Environmental Hygiene
Year 2010
Convention or series no.
Author(s) Stefaniak A.B., Harvey C.J., Bukowski V.C., Leonard S.S.
Title Comparison of free radical generation by pre- and post-sintered cemented carbide particles
Bibliographic information Jan. 2010, Vol.7, No.1, p.23-34. Illus. 56 ref.
Internet access Comparison_of_free_radical_generation.pdf [in English]
Abstract Rapid generation of reactive oxygen species (ROS) may occur in response to cellular contact with metal particles. Generation of ROS by cobalt and/or tungsten carbide is implicated in causing hard metal lung disease (HMD) and allergic contact dermatitis (ACD). In this study, ROS generation and particle properties that influence radical generation were assessed for three sizes of tungsten, tungsten carbide, cobalt, admixture (tungsten carbide and cobalt powders), spray dryer, and post-sintered chamfer grinder powders using chemical (H2O2plus phosphate-buffered saline, artificial lung surfactant, or artificial sweat) and cellular reaction systems. For a given material, on a mass basis, hydroxyl (OH) generation generally increased as particle size decreased; however, on a surface area basis, radical generation levels were more, but not completely, similar. Chamfer grinder powder, polycrystalline aggregates of tungsten carbide in a metallic cobalt matrix, generated the highest levels of OH radicals. Radical generation was not dependent on the masses of metals; rather, it involved surface-chemistry-mediated reactions that were limited to a biologically active fraction of the total available surface area of each material. Improved understanding of particle surface chemistry elucidated the importance of biologically active surface area in generation of ROS by particle mixtures.
Descriptors (primary) free radicals; particle size; alloys; hard metal pneumoconiosis; risk factors
Descriptors (secondary) tungsten carbide 1:1; cobalt; determination in tissues; cell culture; comparative study
Document type D - Periodical articles
Subject(s) Metal production and metalworking
Occupational pathology
Toxic and dangerous substances
Broad subject area(s) Occupational medicine, epidemiology
Chemical safety
Browse category(ies) Pneumoconioses
Metalworking industry