Document jX7zE36RJRqnGqNkov16Qdn9

Augrurt 15, 15bB Hr. E. K. Jackson Safety Engineer .. Johi^-^inville Corporation 22 East both Street Kerw Tore 16, H,, I. 2-e: Dominic 5ertogiiat P-bB-bl5 ____ Tear Er, Jackson t Te hare forwarded our report concerning the shore cane to Doctor Berdei, Pathologist, St. Eary's Hospital, b29 East Third Street, Duluth $, Eirnesotk. i-B you fill recall Tran previous correspondence, he made the material available. to ns Tor study and requested a copy of the report concerning our findings and interpretati cm. Although individual susceptibility has been m--ntiemsd often to explain the variable incidence of palmnary dxsage in a group of employess similarly exposed to harmful dusts, nevertheless w* hare never been able to Qes costrate the existence of natural or hereditary factors which right account far such rgri ability. Ex perimentally, different animals of the same species react essen tially the sac-- to similar exposures. In contradistinction, bew^rer, there are acquired factor* which play a significant role. The major one of these is of the respiratory system, Whether active or healed, it ray alter the fimatacy and physiology of that ay*tern thereby allowing greater J>*a-- grexa of the harmful agent into the lung permitting c*=*aivTB pul monary retention mod stimulating inflammatory reaction. In addition, there are other seemingly important factors, including pnrrioua duat aporor*, which asy nodify the reaction to other dust inhaled in mh^qtcat unrelated expesuras. Thus, the bituvlroux coil minacr and tbs benatite miner react differectly to silica than do tho without previous exposure to dust. Age ard gtoecral health might also b jssintained as acquired predisposing factors. H V. JacVaan Johns-Jianville Corp. August 19, 19l8 Page 2 In general, it Is cost difficult to evaluats th role of -indi vidual susceptibility as a determinant of the pulmonary condition resulting frcw exposure to a dost. It Is clearly established that the nineralogic composition, the particle sise, the atmospheric con centration and the deration of exposure are of prise importance in the etiology of any pulmonary carnage resulting from the inhalationof cusrt. In consequence of the above, I c-an see no other alternative than to anticipate others aith similar exposures to he similarly affected, but I expect also that individual susceptibility will ef fect sene selection. Sincerely yours AJ7 :trr Arthur J. Vcen=ald, V. B. Director