Saranac Laboratory, Interim Report on the Biological Activity of Kaylo Dust (1948)

A nine-page interim report of October 30, 1948, to the Owens-Illinois Glass Company, submitted by Dr. Arthur J. Vorwald of the Saranac Laboratory with Philip C. Pratt, Thomas M. Durkan and Anthony B. Delahant. Guinea pigs breathed Kaylo dust eight hours a day, at an average of 116 million particles per cubic foot of air. Up to 30 months they showed no fibrosis, but all nine animals killed after 30 months had fibrosis "identical with asbestosis." The report concluded that Kaylo, "because of its content of an appreciable amount of fibrous chrysotile, is capable of producing asbestosis and should be handled as a hazardous industrial dust."

What it shows

The report said the findings at three years were "strikingly different" from those at two and a half, so the tentative conclusion of 1947 that Kaylo acted as an inert dust "must now be altered." Kaylo did not cause silicosis. A section drawn from Saranac's unpublished asbestos research for "certain other supporting companies" was to be "considered confidential"; it said that "very small numbers of fibers are capable of producing asbestosis." The report closes with early results of new experiments on Kaylo and tuberculosis. It came with Vorwald's letter of November 16, 1948; both are already published together as a chronology page.

In Johns-Manville's index

Johns-Manville's legal department indexed the Motley 1,000 in 1984. Its index describes this document as follows:

"Interim Report Regarding the Biological Activity of Kaylo Dust," submitted to OIG, Toledo, Ohio, authored by Dr. A. J. Vorwald, 10/30/48.

Related documents

• Arthur J. Vorwald to U. E. Bowes on Kaylo Producing Asbestosis in Animals (1948)

About this copy

This is document 232 of the Motley 1,000, from the set the Manville Personal Injury Settlement Trust's records facility certified as true copies, pages CRMC-Motley1000-Subj-001345 to CRMC-Motley1000-Subj-001353.