Application of intratracheal instillation exposure to the etiological determination of a pulmonary disease outbreak: nylon flock as an example.
Inhalation toxicology, second edition. Salem H, Katz SA, eds. Boca Raton, FL: CRC Press, 2005 Dec; :109-117
Our IT instillations with nylon flocking materials provided useful insights into important toxicological differences between different occupational agents, namely silica and nylon flock. These studies are even more interesting in view of recent advances in pulmonary immunology. The studies indicated that, of the agents investigated, the airborne dust collected from the worksite was highly inflammatory and was also more inflammatory than the components of the dust that were tested. Retrospective comparisons with other IT instillation experiments of occupationally important agents previously conducted in our laboratory supported the highly inflammatory nature of these dusts (Porter et al., 1999). In general, such comparisons are accepted as a valid use of data obtained from studies using the IT exposure technique (Driscoll et al., 2000) and could not have been conducted in a timely fashion by inhalation exposures. In addition, this study showed that the respirable nylon fibers that were a component of the workplace dusts were highly inflammatory and that some fibers persisted in AMs in the lungs of rats for at least 4 weeks and were associated with focal histocytosis. In view of recent evidence regarding the role of AMs and inhaled dusts in altered pulmonary immune response, the persistence of these workplace fibers in the lungs of exposed rats indicated that these fibers played a potentially important role in the etiology of this disease outbreak. The example above indicates that when appropriate consideration is given to the design of an experiment Utilizing IT instillation exposures, the data obtained can provide information relevant to human inhalation exposures. In this case, the study provided crucial evidence that suggested that the etiological agent causing an outbreak of ILD at an industrial plant was a respirable fraction of nylon shreds produced during nylon flock production.
Immunology; Immunotoxins; Fibrous-dusts; Pulmonary-system-disorders; Respiratory-system-disorders; Lung-disorders; Lung-fibrosis
Inhalation toxicology, second edition