Document Z4owQZBd4JNxvpLM883wn9JG7

FILE NAME DuPont DUP DATE 1968 Jan 10 DOC DUP055 DOCUMENT DESCRIPTION Letter to Kenneth Keuper from G.J. Stopps RE Reading Dust Counts and Questions to Investigate about Asbestos Contribution to Lung Disease of in 5-00227 vi -.., January 10 1968 ENG L 1285 \ ce tf I was pleased to hear from you consitd hae t cronasit dei rao tin on is being given to monitoring the dust levelast 21 construction sites around the country at regular intervals ae I should like to suggest i mined for asbestos so that but also what fraction of the that some of these dust not only will the total count is asbestos samples be count be known A further point that is important at the moment is the type of asbestos being used Since there is some evidence but certainly not enough for a dogmatic statement that the type of asbestos may be important in determining whether cancer is produced At this time crocidolite is felt to be possibly more of a risk then chrysotile or Emosite In line with this current feeling I am enclosing the tentative values being suggested by the A.C.G.I.H. for the TLV for bestos The recommendation made is nothing but a proposal at this me but is indicative of the trend of industrial hygiene thinking ortunately these tentative TLV's are often vidence by labor unions and state regulatory taken as bodies prima facie A further straw in the wind is a recent report on smoking amongst asbestos workers which indicates that the smoking asbestos worker has a Ightly increased chance of dying of chest disease compared with the smoking asbestos Worker but that the asbestos worker who smokes shows a much higher death rate due to respiratory disease than does the smoker who is not exposed to asbestos In summary it seems essential to know 1 The dust exposure 2 The type of asbestos 3 The state of health of asbestos exposed workers at least at the time they are hired and at the time of discharge I have counts and spoken to Jim Morgan about the matter of reading the dust we will be sending you & cost estimate in the near future ORIGINAL Signed by G. J. STOPPS G. J. Stopps M.B. Chief Physiology Section pgh . iclosure