Document rpX3E8pqKRp4ag4y7bBLNwQ60

Jun e 13, X93+1 b p . .Joseph k e lso n 1<?0 -ist 39t h t r e a t Haw f o r k r Dear Doctor Felsen: I aia so r r y t h a t I d id n o t havo a ch an ce to se e and t a lk w ith you in C lev elan d . However I was on ly th er e fo r a sh o r t t l -e and p r a c t i c a l l y a l l o f ray t i n e w as taken , w h ile I w as t h e r e in t a lk in g w ith v ar io u s p eop le abou t our e x h ib it . 1 was in t e r e st e d in w hat you h ad .to say abou t the d isc o lo r a t io n o f the in t e s t in a l n u oosa. A c t u a lly I h ave n ever had o ccasio n to look fo r th e co n d it io n you d e sc r ib e th rou gh th e u se o f th e p r o c t o sc o p e , I h ave seen t h is co n d itio n in exp er im en tal an im al3 and I h ave no doubt i t e x i s t s I'r e ay xe n t ly i n th e human b e i n g . I h ave h ad o c c a si o n t o 3o t h i s c o n d i t io n in t h e e x t e r n a l a n a l t i s s u e s and I t h in k t h er e i s v e r y l i t t l e q u e st io n t h a t i t i s d i s c e r n i b l e much m ore fr e q u e n t l y t h an I s a l e a d l i n e i n th e g i n g i v a l t i s s u e s , I s h a l l be v e r y much i n t e r e s t e d i n y our a r t i c l e b u t X am a f r a i d we s h a l l n o t b e a b le t o c o n t r ib u t e much i n t h e way o f a d d i t i o n a l in fo r m a t io n . One r e a so n fo r t h i s i s , o f c o v r so , t h a t a l l o f th ese o b se r v at io n s h ave as t h e ir pu rpose th e d e t e c t io n o f abn orm al q u a n t it ie s o f m e t al a s a means o f e st im at in g th e m agn itude o f th e exposu re to m etal compounds w h ich giv e r i s e to a b la c k su lp h id e in the b o d y . Our own e x p e r ie n c e h a s b e e n c h i e f l y w ith , l e a d b u t we h av e a l s o h ad some i n t e r e s t i n t h i s same p r o b le m , p a r t i c u l a r l y i n t h e c a se o f b ism u t h . In b o t h i n s t a n c e s , h ow e v e r , we h av e h ad f a c i l i t i e s f o r t h e d e t e r m in a t io n o f the m agn itude o f th e le a d exposu re In very p r e c ise term s, a s determ in ed by th e stu d y o f th e le ad con ten t o f th e e x c r e t a , b lo o d o r t i s s u e s . H avin g su ch in fo r r aat io n we h av e p o t f a i l e d t o Ja k e t h e u s u a l o b se r v a t i o n s as to th e e x ist e n c e and ch ar act e r o f a le ad lin e , bu t we h ave n o t r e s o r t e d t o t h e u se o f t h e p r o c t o sc o p e . I may sa y fu r t h e r m o r e t h a t alt h o u gh t h i s i s a v e r y i n t e r e st in g an d, I th in k , u se fu l proced u re, i t cou ld h ard ly be u sed r e g u la r ly or even fr e q u e n t ly in in d u st r ia l p r a c t ic e a s a means o f d e t e c t in g evid en ce o f abn orm al le a d e xp o su r e. 2 Mo d ou b t you w i l l r e a l i z e t h a t on e o f t h e m o st im p o r t an t a sp e c t s o f ou r work h as been th e o r a c t lc a l c o n sid e r a t i o n o f how u n d er i n d u s t r i a l c o n d it io n s one cou ld determ in e th e e x ist e n c e o f h azar d ou s le a d e x p o su r e . Th is*, we b e l i e v e , i s don e m ore e f f e c t i v e l y by th e stu d y o f th e le ad con ten t o f th e blood or o f tnr* e x c r e t a , th an by an y o t h e r m ean s. C o r d ially y ou rs, RAKsis Keh oe, M.D.