Johns-Manville Manual Sheets on Diatomaceous Earth as a Potential Health Hazard (1960)

Five pages from a J-M sales manual, section 120, headed "Diatomaceous Earth as a Potential Health Hazard," with sheets revised July 1, 1960, and June 15, 1957. The sheets are to be used "as a basis for giving verbal answers" to customers, and "if written confirmation is requested, please refer the matter to Division Headquarters." They summarize the U.S. Public Health Service's study "Pneumoconiosis in Diatomite Mining and Processing": powders containing cristobalite, such as J-M's calcined Super-Cel and Hyflo Super-Cel, "can cause pulmonary damage when inhaled," while natural powders "cause little if any trouble."

What it shows

The sheets record a change in J-M's labeling. A caution label had been put on all diatomaceous earth bags (the plant manager at Lompoc, California, was told on November 16, 1951, to print it on all new containers), but after the Public Health Service report (Cooper and Cralley, 1958) it was taken off bags of natural powders and kept only for cristobalite-bearing grades: "Inhalation of diatomaceous earth dust may be harmful. Avoid breathing this dust." The sheets also quote the Lompoc plant physician, Dr. Walter M. Anderson, on diatomaceous earth pneumoconiosis, and close: "There is nothing to hide. We welcome any inquiries as giving opportunities to kill rumors and to have the facts known."

In Johns-Manville's chronology

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

J-M Manual insert concerning diatomaceous earth as a potential health hazard. (Some pages are dated 1957.) The information in the insert is to be used as a basis for answering customer inquiries. Discusses J-M's support of the extensive and continuing research of the Saranac Lab, IHF and USPHS regarding the diatomaceous earth health hazard. Mentions the great program at Lompoc to eliminate dust. States that a vigorous housekeeping program and regular industrial hygiene surveys, whose results are correlated with the results of physical exams, have enabled J-M to prevent any new cases of industrial pulmonary disease among its Lompoc employees.

Discusses the caution label which J-M has placed on bags containing certain diatomaceous earth products. (Mentions that on 11/16/51, the Lompoc Plant Manager was instructed to print a caution notice on all future containers. The language of the notice was recommended by the Manufacturing Chemists' Association. Later, as a result of J-M health researched the results of the 1958 USPHS report, the caution label was removed from all bags containing only natural and non-cristobalite powders.)

States that the following advice should be given to customers: They should minimize as much as possible the dust created by the use of the materials if the nature of their operations will not permit the reduction of the dust concentrations to safe levels, personal protective devices should be required. Further inquiries by customers should be directed to Division Headquarters. along with any requests for a written response. A statement by Lompoc plant physician Dr. Walter M. Anderson is attached. Dr. Anderson discusses diatomaceous earth pneumoconiosis: its diagnosis and prevention.