Document 4QBL5VLXkxLZ8EL92eedbp6da

FILE NAME: WR Grace (WRG) DATE: July 10, 1968 DOC#: WRG153 DOCUMENT DESCRIPTION: 1968 Letter to Mr. Lovick regarding dust exposure at vermiculite mine > * NATIONAL C C N T * row U AH ANO IN D U STR IAL H E A L T H 10 14 8 A O A O ff A Y Ci n c i n n a t i , O hio S202 D E P 'iR TM E N T O F H E A L T H . E D U C A T I O N . A N D W E L F A R E PUBLIC H E A LT H S ER V IC E July IQ,' 1968 REFER TOi Mi. E. Lovick Plant Manager Zonolite Division W. R. Grace and Company Libby, Montana 59923 Dear Mr. Lovick: I have discussed the situation at your vermiculite'mine and mill ` * with Dr. Cralley and other members of our Field Studies staff. One of the problems in assisting your abate excess exposure to dust is our Lick of knowledge of the effects of tremolite asbestos. In our report we will assume that the biological activity of an airborne tremolite asbestos fiber is similar to other forms of ' asbestos. However, we can base this assumption on analogy only; we have no direct data relating exposure to tremolite asbestos to the health of workers. For the Fast five years the Occupational Health Program has been conducting an epidemiological study of the asbestos products industry. This research study was requested by the major asbestos product manufacturers to define the health hazards associated * with asbestos .so that adequate engineering and medical controls could be applied. We have surveyed over thirty plants to date including users of chrysotile, crocidolite and amosite but we have not encountered tremolite asbestos exposures. A major portion of this study involves the assembly of groyps or cohorts of workers with a certain type of exposure. The names and social-security numbers of these individuals are submitted to the Social Security Administration who report back to us with the names of those who are dead. We then obtain death certificates and are able to construct mortality tables for comparison with other similar non-exposed groups. In this way we can estimate the nature and degree of risk associated with exposure in the industry under study. 171A5I 2 Mr. E. Lovick - 7/10/63 K\ In order Co define the risk associated with trcmolite asbestos exposure we would like to include the iJ. R. Grace Zonolita plant in our asbestos cohort study. To do this we would need the following information on all active and inactive employees who S*' have worked for at least one month: Name Social Security Account Mo. Date of Birth *;*v Date(s) of Hiring Date(s) of Separation (if inactive^ , Work history In other industries it has been found convenient for both the company and ourselves for us to microfilm the-records at the plant personnel office. If you feel this would not be practical, an t extract from the records containing the above information would ifV be satisfactory. The data obtained from your records and from * the Social Security Administration is for our internal statistical use only and we will not attempt to contact any individual. We hope that you will be able to participate in our study since it is only through this sort of investigation that the health hazards associated with tremolite asbestos can be accurately defined. Sincerely yours, / I > ecu Jeremiah R. Lynch Asst. Chief, Environmental Activities Field Studies Occupational Health Program 20171452