Canine tracheal mucus transport of particulate pollutants: comparison of radiolabeled corn pollen, ragweed pollen, asbestos, silica, and talc to Dowex anion exchange particles.

Canine tracheal mucous transport rates of each of two organic (corn and ragweed pollen), and three inorganic (chrysotile asbestos fibers, silica, and talc), 99mTc labeled pollutants were simultaneously measured against those of 125I labeled Dowex anion exchange resin particles in healthy animals. The method of labeling of the pollutants with 99mTc is described. With the exception of ragweed pollen, which moved 15% faster than the reference marker (P <.02), we found no difference in the transport rates of these particulate pollutants and the reference marker. We conclude that the particulate pollutants studied are handled by the mucociliary system in a similar fashion, and that the transport rates of Dowex particles represent valid measurements of the transport rates of these pollutants.