Document grJgVbGBM3aO8vyr08KxVyaG

FILE NAME: ALCOA (ALC) DATE: 1941 Mar 25 DOC#: ALC058 DOCUMENT DESCRIPTION: Letter .. 3>r, .F rau els C F rary . : -V ''''luMhuni .Companyof-America- v:v.i'..',.vPo?'0jpfi-;8o-* 7 7 2 :,* V?. > .: ! iHmewr' KS efinnsaIinrugrttoan,. Pa-. : .H ..* - t'. . Y \ V. -. ? 1 . '`v ; Baajs B ri P rary s ' ,,' . 4 "... , */* V,w.-*-*** & '-,-' - /' . ' ; fS* ... I fe a r; t h a t 'aia jjgotng to iaske' a .nuisance 'o fy ' . m yself1because o f y / Ignorance o f ,-the- p h y sic a l chem istry o f mtiaarok'w^pcHiP^;isn a-TJattsfe^i^.ny-' co n v ictio n th at;: a l t e r a t i o n s of s o lu b ility o f quartz in vitxtf d o n d t p a ra lle l the. evidences 'dit/ .p ro te c tiv e .ab tio a> o b tih ed e s p y rlc a ly by animal i n j e c t i o n s , %U: - f a c t r ;own o b se rv a tio n s h a v e d ls clo sed n&ny co n d itio n s t h a t a r e a t "variance w ith th e 's o lu b ility hypothesis of the actio n of quartz . in th e body \ , ' We, f o r example, have in je c te d a g r e a t num ber'of s i l i c a t e s in to anim als Which y ie ld ore soluble s i l i c a in th e teat tube th an q u a rtz and y e t th e se s i l i c a t e s ,have provoked ho . , fib ro s is or any o th e r' se rio u s 'reactio n .' Our pbnp&ratlve t e s t s - o f e o l u b ilit y were made .Upotf^s*pure!' z ^ e r a l i f a s i t `"was p p e k i^ ^ V : 5-* .J*j.s............ f o r an e ^ e r ie n c e d ,p e tr o g r a p h r ` t o ' e le c t'a n d ,'w h a t was equally:.. -T-^ iHw' v k - ( "lasportant#,,.upoia. e lu trla te d ;jp a rt c ie s V `,o f a standard s iz e ran g e - - v :* c f - ,ls t o ;-5'mierbneV'. -V- -Jr ' **JL$skr.%i.- '' '* . repeat edl y*hade <0`v .. i an a ly s i s and no l i n e s except th o se f o r n o rm a lq u a rtz on x--ra y - d i f f r a c t i o n . I n v a t e r underoompar&bla co n d itio n s i t gave o n ly ;'*,* - 8 .9 p a rte per m illion soluble s illo a w ith a depression of sol u b i l i t y o f 35.5 p er cent, on th e 'a d d ltio n .of th e aluminum in - . ' `saaV quantities. ' . ?V '/ * ' .. In sp ite of the very obvious decrease in the . j w - ; ''b e n t of .soluble s i l i c a r e s u ltin g from th e ad d itio n of the - aluminum powder In th e t e s t tu b e -th e l a t t e r , substance in fo u r s e p a ra te ,,animal exprim enta had no e f f e c t upon th e u su al r e a tio n e :i p r o d u c e d b y o u r q u a rtz duefe. ..Two o f th e s e were made w ith thVtsa^v?^'1 h e a t&vpwer.. a f t e r we-bad le a rn e d .-o f1;th e ;.p o s s ib ility th a t heat* m ight destroy i t s p ro te c tiv e motion. I could only In fe r th a t, 4a- ag ip g '-vthe. powder had been, o x ld iie d to. su c h an e x te n t that., i t .no. logar. in h ib ite d 'w a r t ; o r th a t .'possibly- th ere were p a o u lia r iti a ` ` in - o u r a t b r j although i t .was'd i s t i l l e d i n g la ss,, which were .;% ' d iffe re n t'fro m these o f the Toronto supply. / ^ J, *",, * . . i t /"'**' m* . ` **/,., *.- '*. . ; " On th e o th e r hand we have obtained evidence o f V ' . -, h ig h ly S a tis fa c to r y p ro te c tiv e a c tio n w ith th e two forms o f . ' v - aluminum hydroxide about which 1 f i r s t wrote you a n d .th e ir e f f e c t upon the so lu b ility of quartz in the test-tu b e are e sse n tia lly th e same. With i t the percentages of red u ctio n in s o lu b ility o f th e two above mentioned O n tario q u artz were 97.6 and 99.5 r e sp ectiv ely . In a long se rie s of experiments w ith the hydroxide w hich were s ta r t e d independently o f th e O ntario work some s i x months' b efo re we had heard o f t h e i r work, we have re p e a te d ly found ,, that* a n im a ls.were, as com pletely p ro te c te d a g a in st s i l i c o s i s 'as . : v - :thosV* t r e a t e d w ith th e m e tal'by Denny, Hobson and Irw in . H o st 'o f o u r t e s t s were made by in je c tin g b o th th e quartz and ..th e 'hydroxide l a `brdsr. to e s t a b l i s h p r in c ip le s governing th e b eh av io r of. 'the;two;..'- \ ohem ichls i n th e liv i n g body. iS were f i n a l l y co n fro n ted w ith '.th e -Vr p r a c tic a l t e s t o f g e t tin g th e 'In h ib ito r substance In to .the linage* T a iX ia o sis develops*'''snd 'coaoluded, as d id -th e;'.O et^ io 7v.'.'''.. ..In h ala tio n was th e only p r a c t i c a l means o f accom plist~: -ling this^purposei . T_h_en cam.e-_t_he';p_roble_m o. f. f__i_n _d _in_g__a__fo_r_m of-`th e `tv; " t. . hydroxidar that ifae.stable and' would sake an inhalable' dust.; m s first le tte r to yoa. ,-v"tekv.* - ';*i*.;-. - >:V' h e lp i n determ ining: th eXet'-natu!r'?cf''f'/ 5 - th e . compounds .w ith which we have a lre a d y .worked a n d .f o r t h a t * v '?". #. * . ` * .* < . ; - . ^ .F liiep .;an d ifaBli re s id u e w ith hot; w ate r u n t i l no t e s t =for ; '.ch lo rid e s i s o b ta in a b le . * . v ,* .. ,,.iafc are th a t th e re sid u e does n o t d ry on. th e f i l t e r . . V*t'}*?*' J-iv y J $$: v. i.'-Y' ~ ;pH;.pf.::*8 t o 6 ,4 . , - J - . . '. . '. . f '<'- .V. 'S&a&ovosttee .toreeiplt$td.,^dw4r#';V` r6ceed as b e f o r e o u t, theft, , ' -;r ^aiioff.-the '^ ft^ rid e -fr ^ 4 fa 3 A t v O h ;r^ h e ' f i l t e r p a p e r ' to.-.dry- ' " - i ri i f -f: inAm ... . *. __ __ _ _ ra tu re f o r "48 h o w s;; , ...';'- 1` . in vacuo a t rooa ; ,jV 'drihd in an ag ate m ortar and''suspend'- in", w ater f o r in je c tio n in to animals. . -' : ^ .. v--. We have supposed th a t b o th o f th e se p ro d u cts w ere tr ih y d r a te s as th e l a t t e r one h$A not been su b je c te d to - h e a t In th e process of d ry in g . We know th a t they a re s ta b le because h ath o f them:have given, good p r o te c tio n in ania& ls e y ea r o r more a f t e r th e y were made. I f th e l a t t e r one should prove to be a substane ' which can be produced cheaply- and our in h a la tio n te s t dem onstrates 'i.r7- /,s. th a t i t form s'an inhalab ia d u st I t might c o n s titu te a s u b s titu te fo r th e m etal which a p p a re n tly snaat-;toe f r e s h ly ground t o be. o f b e n e f i t . B e fo re g o in g f u r th e r , however, we m ust..prdya";lt ?-'f : ';> .'v... > /say- 1 thank you- for^your- .halp. and a d v ic e , > `if-V v- ' .-'!'".. . 'i'. ./*'-; .-> : c :' : . , ., . v " . . ..: -- : '*X:-TV/;:i'iSi*i.io. rly you.rs , *." ** .`v*-:';W*ri :V t V>.`* .!.*.*? * .*:5*> *.T'a-.hV, .*. i '*3*.` ; X. * [ 'i f * * . -v f : > ' . ' f' ** . ** '*, Vr *. L '/V ! - - ` ^ *-V/> *:ij}. -? eroy tl.;'Q^dheri;;li;;p.^ " ;:vlv\y ^ - v # .*.*-T D i r s c t o r '' ' *v " ! . .