Kenneth W. Smith to J. P. Woodard Naming Asbestos and Silica as Possible Causes of Lung Cancer (1950)

A one-page confidential memo of February 7, 1950, from Dr. Kenneth W. Smith of Canadian Johns-Manville to J. P. Woodard at J-M headquarters, answering Woodard's question about lung cancer. Smith agreed with Woodard on the diagnosis, compensation and prevention of silicosis. He wrote that lung cancer was recognized as an occupational disease in some industries and that, as far as J-M was concerned, "I know of two hazards in our operations which may lead to pulmonary malignancy, namely asbestos and silica." Although he had not seen the condition in J-M's operations, he had no reason to believe it could not exist.

What it shows

Smith closed by stressing the need for "a complete picture of the relationship of asbestos and lung cancer," to be learned from experiments and actual operating experience, so that the company would know whether a hazard existed and what to do to prevent it. The memo answers Woodard's request of February 3 (Woodard to Peterson). Here J-M's own medical director told headquarters in writing that asbestos was one of two materials in its operations that might cause lung cancer.

In Johns-Manville's chronology

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

Dr. Smith writes to Woodard on 2/7/50 stating that "I know of two hazards in our operations which may lead to pulmonary malignancy, namely asbestos and silica." Although Dr. Smith has not seen this cancer at J-M, he has no reason to believe it could not exist. He encourages further study: experimental and actual operating experience.

Related documents

• Arthur J. Vorwald to Kenneth W. Smith on Reviewing Asbestos X-Rays for Lung Cancer (1949)
• Arthur J. Vorwald and Kenneth W. Smith on Lung Cancer Among Canadian J-M Workers (1950)