Kenneth W. Smith, "Asbestosis," Chapter 2 of The Pneumoconioses (1955)

A 13-page reprint of Chapter 2, "Asbestosis," by Dr. Kenneth W. Smith, medical director of Johns-Manville, from a book titled The Pneumoconioses. Much of it follows his 1955 journal article: the types of fiber, the X-ray stages of asbestosis, and the 708-man mill survey. Near the end Smith writes that "It is entirely possible that the asbestos fibre may be a carcinogen, or a co-carcinogen," but that the true relationship would "remain obscure until responsible reporters can evaluate the relationship between agent and disease and not just job title and disease." In his own eighteen years and "over 50,000 physical examinations," among workers "exposed only to chrysotile fibre, there were no more cases of pulmonary malignancy than among the general population."

What it shows

Smith objects that "The term 'asbestos worker' has been used too freely," since it often meant a member of the Asbestos Workers Union, insulators who also applied mineral wool, glass fiber and magnesia, and says reports linking lung cancer and other diseases to "the asbestos worker" had relied on job title. His own article that year had called the cancer question "extremely difficult to confirm or deny" (Pulmonary Disability in Asbestos Workers). That summer an insulators' union official reported that seven of his local's last nine members had died of lung disorders (Kane's letter).

In Johns-Manville's chronology

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

Affirmative Misrepresentation. Chapter 2 "Asbestosis," written by Dr. K. Smith, circa 1955. Dr. Smith states that it is possible that asbestos fiber may be a carcinogen or a co-carcinogen. Among those workers who Dr. Smith has followed over the last 18 years and who have been exposed only to chrysotile fiber, there have been no more cases of lung cancer than among the general population.