Document jyV1x2Mzo6vgNjy9pvDLRjOON

- - - - --^vj;.53esto3 Workshop iit review JULY 18-20. 1977 NATIONAL BUREAU OF STANDARDS ATTACHMENT 1 Page 1 of 2 The workshop was organized to discuss a definition of asbestos and suitable measurement methodB for regulating against asbestos health hazards, prior to the issuanoe of a standard. Four hundred persons from the mining industry, asbestos manufacturing, U.S. and Canadian health agencies, and medioal and research facilities attended the workshop. The National Bureau of Standards concluded in May from analysis of 80 industrial Bamplos that OSHA's present techniques for analyzing for asbestos in industrial talc is useful only for determining fiber content and not asbestos content. This and other unresolved issues were discussed at the workshop. Divergence of opinion was esq^ressed in two camps; U.S. Government Agencies and Medical represent atives v.s. Industry and the U.S. Geological Survey. The Bureau will consider theBe viewpoints in making its final report to OSHA. Significant segments of the proceedings include the followings Mearl Stanton. National Cancer Institute Cancer-causing danger of fibrous materials is related to fiber dimension. Greatest carcinogenicity came from fibers with dimensions that were equal to or less than .25 ^ by more than 8 . Smaller fibers were controlled by phagocytes# in the body. Knowledge on why long fibers are carcinogenic is presently inadequate. Continued effort must be done on inhalation studies to allow extrapolation to human experience in understanding the effects of asbestos. 011437 Paul Kotin. Johna-Manvills Corporation. Denver Exposure to Asbestos under the present standard level does not result inevitably in lung canoer, mesothelioma ' or asbestosis. There is no such thing as a single threshold for a carcinogen but a series of thres holds can be identified. Nothing rules out a dose-response relationship for asbestos. William Nicholson. Arthur Langer. Mt. Sinai/Hosoital- N.Y. Thresholds exceed present scientific capability. Excesses of lung cancer and mesothelioma from mortality studies were cited from job related asbestos exposure. In one study spouses, children and other family members of workers in an amosite asbeetos factory were studied for asbestos related disease. Out of 626 persons, approximately one-third were found to have abnormal lung i-rays. # phagocyte - white blood corpuscles that ingest and destroys organisms or particulates that result in disease. PRODUCED BY FORD SCF-ALLF-06500