W. G. Hazard of Owens-Illinois to Ira I. Brought on Kaylo and the Saranac Experiments (1956)

A one-page letter of June 12, 1956, from W. G. Hazard of the Industrial Relations Division of Owens-Illinois to Ira I. Brought, a Toledo consultant, sending a reprint of the Saranac Laboratory's published article on animal tests of Kaylo, Owens-Illinois's calcium silicate insulation. Hazard writes that the experiments "showed conclusively there was no silicosis hazard," but that animals exposed for a long time to high concentrations of Kaylo dust "could develop a mild asbestosis reaction," milder than from 85% magnesia, and that "Asbestos workers and applicators are exposed to higher concentrations of asbestos dust during their normal work than would result from handling Kaylo." He adds that yearly examinations and chest X-rays of Kaylo plant workers had found no lung changes from their work.

What it shows

Saranac had told Owens-Illinois in 1948 that every animal exposed to Kaylo dust developed "unmistakable evidence of asbestosis" and that Kaylo "should be handled as a hazardous industrial dust" (Vorwald's letter of November 16, 1948). Writing to an outside consultant, Hazard describes the finding as a mild reaction and compares Kaylo favorably with the asbestos dust insulators already breathed. The attached article is written up separately (Schepers, Durkan and Delahant).

The date

The year on the letter is hard to read ("195_"), and Johns-Manville's chronology lists it under 1955. It cannot be from June 1955: the reprint it encloses is from volume 12 of the A.M.A. Archives of Industrial Health, an article received for publication on July 15, 1955. The office memo filed with it, about the same telephone call from Brought, is marked "6/22/56," so we date the letter June 12, 1956. The same letter, without the reprint, is in the Motley 1,000 as document 187.

In Johns-Manville's chronology

Johns-Manville's own chronology of what the company knew describes this document as follows:

In a letter dated 6/12/55, W.G. Hazard (Owens-Illinois) writes to I. Brought and states the Saranac experiments showed conclusively there was no silicosis hazard to Kaylo dust because there "is no free silica in the product." He says that Saranac found that if animals were exposed to high concentrations of Kaylo dust for a long period of time, then they could develop a "mild asbestotic condition." This reaction was milder he says than would result from breathing dust of the commercial product with 65% mag. "Asbestos Workers and Applicators are exposed to higher concentrations of asbestos dust during their normal work than would result from Kaylo."

Related documents

• Arthur J. Vorwald to Owens-Illinois on Kaylo Causing Asbestosis in Animals (1948)
• Saranac Laboratory, Final Report on the Capacity of Inhaled Kaylo Dust to Injure the Lung (1952)
• Saranac Laboratory, Report of Industrial Hygiene Survey of the Owens-Illinois Kaylo Division Plant (1951)