Tungsten oxide fiber dissolution and persistence in artificial human lung fluids.
J Phys: Conf Ser, Inhaled Particles X 2009 Mar; 151(1):012013
Tungsten is a dense metal that is used in a range of industrial applications, including non-sag wire for light bulb filaments. During the conversion of tungsten oxide powder into tungsten metal powder for use as filaments, aerosols may be generated which contain tungsten sub-oxide particles having fiber morphology. To evaluate whether these fibers pose a yet unrecognized inhalation hazard due in part to their biodurability, we characterized the physicochemical properties and measured relative dissolution of fiber-containing (WO2.81, WO2.66, WO2.51) and isometric-shaped (WO3.00, WO2.98) powders in artificial lung fluids. Raman spectroscopy results present a shift in the main frequencies for tungsten oxide samples that were sonicated in surfactant, confirming a decrease in the size of the crystalline domains by de-agglomeration. Geometric mean fiber aspect ratios were 8.3 (WO2.81), 7.9 (WO2.66), and 6.9 (WO2.51). In artificial extracellular lung fluid, alkylbenzyldimethylammonium chloride (ABDC), added to prevent mold growth during experiments, inhibited (p < 0.05) dissolution of WO2.98, WO2.81, and WO2.66. Less (p < 0.05) of the fibrous WO2.66 and WO2.51 dissolved relative to W metal; however, biodurability was only modestly greater than W metal. These data are useful for understanding the inhalation dosimetry of fibrous and non-fibrous forms of tungsten oxide materials.
Aerosols; Biohazards; Biological-effects; Biological-factors; Breathing; Chemical-properties; Chemical-reactions; Chronic-exposure; Exposure-methods; Health-hazards; Inhalation-studies; Laboratory-testing; Lung-disorders; Occupational-exposure; Occupational-hazards; Occupational-health; Occupational-respiratory-disease; Particle-aerodynamics; Particulate-dust; Particulate-sampling-methods; Pulmonary-system-disorders; Risk-analysis; Statistical-analysis; Work-environment; Workplace-studies
A Stefaniak, Division of Respiratory Disease Studies, National Institute for Occupational Safety and Health, Centers for Disease Control, 1095 Willowdale Road, Morgantown, WV 26505
Journal Article; Academic/Scholarly
Journal of Physics: Conference Series, Inhaled Particles X, 23-25 September 2008, Sheffield, UK