Environmental Health Perspectives 105, Supplement 5, September 1997

[ Citation in PubMed ] [ Related Articles ]

Demonstration of Nitric Oxide on Asbestos and Silicon Carbide Fibers with a New Ultraviolet Spectrophotometric Assay

Per Leanderson, Verner Lagesson, and Christer Tagesson

Department of Occupational and Environmental Medicine, Linköping University, Linköping, Sweden

Abstract
Nitric oxide (NO) has a number of important functions in biological systems and may play a role in the toxicity of mineral fibers. We investigated whether NO might be present on the surface of mineral fibers and if crocidolite could adsorb NO from NO gas or cigarette smoke. NO was determined with a new gas chromatography-ultraviolet spectrophotometric technique after thermal desorption from the fiber surface and injection in a gas flow cell. NO was found in different amounts on chrysotile B, crocidolite, amosite, and silicon carbide whiskers. There was a strong correlation between the amount of NO and the specific surface area of these fibers (r=0.98). NO could not be demonstrated on rockwool fibers [man-made vitreous fiber(s) (MMVF)21 and MMVF22] or silicon nitride whiskers. NO on crocidolite, amosite, and silicon carbide whiskers was readily desorbed from the fibers at increased temperature, while NO on chrysotile B seemed to be more firmly adsorbed to the fiber and required a longer period of time to be desorbed. The amount of NO bound to crocidolite increased from 34 µg/g fiber to 85 and 474 µg/g after exposing the fibers to cigarette smoke and NO gas, respectively. These findings indicate that a) NO adsorbs to fiber surfaces, b) some fibers adsorb more NO than others, c) some fibers adsorb NO more strongly than others, and d) the amounts of NO on fibers may be increased after exposure of the fiber to cigarette smoke or other sources of NO. The biological significance of NO on mineral fibers remains to be investigated. -- Environ Health Perspect 105(Suppl 5):1037-1040 (1997)

Key words : nitric oxide, asbestos, silicon carbide, UV spectrophotometry, cigarette smoke

This paper is based on a presentation at The Sixth International Meeting on the Toxicology of Natural and Man-Made Fibrous and Non-Fibrous Particles held 15-18 September 1996 in Lake Placid, New York. Manuscript received at EHP 26 April 1997; accepted 11 April 1997.

This work was supported by the Swedish Council for Work Life Research (96-0651), the Swedish Medical Research Council (B 95-17X-05983-15A), and the Swedish National Board for Industrial and Technical Development.

Address correspondence to Dr. P. Leanderson, Department of Occupational and Environmental Medicine, Faculty of Health Sciences, Linköping University, S-581 85 Linköping, Sweden. Telephone: 46 13224410. Fax: 46 13145831. E-mail: perle@ymk.liu.se

Abbreviations used: GC-UV, gas chromatography- ultraviolet spectrophotometric; MMVF, man-made vitreous fiber; NO, nitric oxide; UICC, Union Internationale Contre le Cancer; UV, ultraviolet.

[ Table of Contents ] [ Full Article ] [ Citation in PubMed ] [ Related Articles ]

Last Update: October 28, 1997