Document yrNeD0YXgZO1NXNrN08mL62BV

FILE NAME: WR Grace (WRG) DATE: October 21, 1964 DOC#: WRG282 DOCUMENT DESCRIPTION: 1964 Letter to T.A. Williams from Dr. Siemens regarding survey of men working in dusty trades. OCT 251354 ERNMENT OF THE PROVINCE OF ALBERTA"- DEPARTMENT OP PU BLIC HEALTH Mr. T.A. Williams, Manager Grant Industries, Division of Eddy Match Co., 4030 - 8th Street, CALGARY Alberta. . . . . KOMONTON. a u 21 10 64 m t a . ' * Dear Mr. Williams, *' In May of this year this division Initiated a survey of men working In dusty trades inoluding coal mines workers, brick tile, potteries and ceramic3 plants, gravel crushing, lime and ` coment workers, eto.in order to secure quickly a picture of problems involved and conditions leading to them. About 900 men were given breathing tests and had 14 by 17 Inch ohoat X-ray3 done. Among these men were nine working in your ' Zonolite plant at Calgary. Of them 7 produoed foroed breathing curves suggesting some degree of faulty breathing. Of these 7 the radiologist of the Baker .Memorial Sanatorium at Calgaryreported-two'as showing evidence of pulmonary fibrosis, two as having emphysema, one having both fibrosis and emphysema and two with no abnormalities. None of the nine had aotlve^tuberculosis. This number of men with breathing abnormalities in a group of nine is'most unusual and puzzling. The ,materials, used in tho production of Zonolitoft^ro not- 'generally considered harmful except where ground asbestos isu^idded which is done in your plant only occasionally. However, several authorities have reported pneumoconiosis resulting from exposure to mica dusts. Since vormiculite Is a micaceous material this leaves us somewhat uneasy. Wo are oft the opinion that a more detailed study of theso men by a chest specialist would be dasireable. This of oourae would Involve not only the expenditure of money, but also the cooperation of the men con cerned. We would welooma your comments on this problem, We would also be interested in knowing whether N you have the resulta or investigations similar to ours available from the other Western Canadian plants expanding vermioulite. Enquiries have gone out from this office for further information on the effeota of mica dusts on the lungs and lung* funotions of workers. In the meantime it would seem desirable to oonaidor the advisability of the men in the Calgary plant wearing respirators until more definite conclusions regarding the problem oan be reached. A paragraph by our Chief Chemist, Dr. H. Buohwald,1a attached, dealing with our visit to the Calgary Zonolite plant in September *6lj. and the examination of the dust samples collected at that time. We~wish to express our appreciation of the oourtesles and help extended to us by your Supervisor of the Zonolite plant. Hr. Sdttuldt, and Mr. Ralph White, Engineer on your staff, at the time of our September visit. Yours very truly. -- H. Siemens, M.D.. Director, Division of Industrial Health, 328 Administration Bldg. P.3. An extra copy of this letter is enolosed should you require it.