Document GKOEJZ8G8JkBNB7GrGnnMQYZ7

June 1 5 , 1939 D r. K. II. B agehi O ffice o f Chemical Examiner to the Government, Bengal M edical College . C alcu tta, India Dear D octor Bagehi?- 2 have y o u r l e t t e r o f May 1 6 th and th e r e p r in t which you so Mindly s e n t me, and f o r b o th o f th e s e Z..wlah t o e x p re s s my thanks* I am v e ry much i n t e r e s t e d i n th e a n a l y t i c a l d a t a w hich you have p ro v id e d and X am g r a t i f i e d t o f i n d t h a t I t co rresp o n d s in v ery la r g e m easure to o u r own, I have no doubt th a t th e work o f lynch and Tompsett in th is f ie ld \ias very w ell executed but 1 have Very g reat skepticism concerning the "norm ality* o f the tis su e s which th ey examined. I can n o t b u t f e e l th a t Tompsett was dealing w ith c e rta in oases of sig n ific a n t lead exposure, and th a t h is fig u re s f a ile d to rep resen t the tru e p ic tu re of the lead content of the tissu e s of persons w ithout ocoupational o r other accid en tal o r sig n ific a n t exposure to le a d compounds. I t is p o s s ib le , o f c o u rse , th a t co n d itio n s w ith re s p e c t to th e lead content o f food and ' w ater d if f e r w idely in v a rio u s p a r ts o f th e world* However our r e s u l t s obt& ided on a r a th e r la r g e number o f p erso n s in d ic a te th a t I t would ta k e much la r g e r q u a n t i t i e s o f le a d In. th e fo o d th a n a r e . l i k e l y to have e x is te d to have produced: th e p ic tu re xfhich Tompsett found. I t i s q u ite c e r t a in th a t th e average American ta k e s in w ith h is fo o d , q u a n titie s o f le a d which' v ary from one te n th o f a m illig ram to two m illig ram s p e r day , w ith an average fig u re o f approxim ately o n e -th ird of a raH-ligram d a i l y . P e rso n s who e a t la r g e q u a n t i t i e s o f food ta k e in more le a d th a n th o se who e a t s m a lle r am ounts. M oreover p e rso n s who n a t u r a l l y s e l e c t a r t i c l e s low in lead take in considerably sm aller q u an titie s than persons w ith a w e ll m ixed d i e t . M oreover p e rso n s who d r in k w a te r co n tain in g lead up to .02 to ,03 m illigram s p e r l i t e r ta k e in s l i g h t l y more th a n th o s e who d r in k w a te r c o n ta in in g .0 0 2 to .003 m illig ra m s p e r l i t e r . The l a t t e r , how ever, is an in sig n ific a n t fa c to r and need not be considered in re la tio n to the fin a l lead content of the body, since th is q u an tity is very sm all in proportion to th e lead content of the e n tire food in ta k e . A ll of our evidence In d ic a te s th a t w ith in the r a th e r wide v a ria tio n s in d ie ta ry le a d , oftly sm all changes occur in th e le a d e x c re tio n and in the lead content of the tis s u e s . Consequently I P b e lie v e some a d d itio n a l f a e t o r o f le a d exposure be p re se n t I f u n u su ally la rg e q u a n titie s o f* lead a re to be deposited in the tissues* , X am v e ry much i n t e r e s t e d in your p o in t o f view about th e le a d co n ten t o f the h a ir and the re la tio n o f the h a ir to the storage and e x c r e tio n o f le ad * I may s a y , how ever, t h a t X sin v ery sk e p tic a l of th e sig n ific an c e of your r e s u lts on the h a ir * We have had o c c a s io n to s tu d y th e le a d c o n te n t o f the h a ir o f a r a th e r la rg e number o f experim ental an im als \f ith known l e a d c o n te n t in t h e i r t i s s u e s * Xn g e n e ra l we have fo u n d n e g l i g i b l e q u a n t i t i e s o f le a d in th e h a i r even when th e tis s u e s w ere h ig h in lead* In some i n s t a n c e s , how ever, in w hich th e c o n ta m in a tio n o f th e h a i r w ith th e e x c r e ta was u n a v o id a b le , we found q u ite h ig h r e s u lts on th e a n a ly s is of th h a ir . These, b e lie v e , were th e re n u lt o f contam ination of th e h a ir . As a m a tte r o f f a c t , we found i t e x c e e d in g ly d i f f i c u l t , i f n o t im p o s s ib le , t o so c le a n s e th e h a i r t h a t we c o u ld r e g a r d i t a s 1f r e e o f s u r f a c e co n tam in atio n * T h is , X b e lie v e , i s a p ra c tic a lly unsurm ountable o b sta cle in p r a c tic a l work and I doubt v ery much, th e r e f o r e , th e sig n ifican ce o f the determ ination o f lead in the hair* Our o b s e r v a tio n s have ,shown u s to o t h a t le a d a n a ly s e s on th e sk in g ive h ig h ly v a r ia b le re s u lts * The le a d content of' the sk in , as determ ined by analyses o f the ~-kin, h a s ..f a i l e d .to . h av e- any..r e l a t i o n t o ..t h e l e a d con t e n t o f th e tis s u e s * He have come to th e c o n c lu s io n th a t the exam ination of the h a ir is alm ost a u seless procedure since i t Is v ir tu a lly im possible to assu re o u rselv es th a t th e sk in is fre e of e x tern al contami nation. . X ean not but wonder in co nnection w ith th e a n a ly tic a l r e s u l t s , W hether your I n d ia n s may n o t u se some h a i r o i l w hich i s r e l a t iv e ly h ig h in i t s lead, content* In any case I should be very much i n t e r e s t e d in sereins' some r e s u l t s o b ta in e d b e fo re and aftei* the very c a re fu l shampooing o f th e h a ir and scalp of these individuals* In our experience, p a rtic u la te le a d compounds a re so n e a rly u b iq u ito u s th a t it, is p rac tic a lly im possible to avoid gross contam ination w ith lead in th e case o f any and a l l m a te ria ls which can not be cleaned in the chem ical sense* X have re c e n tly attem pted some o b s e rv a tio n s on th e le a d c o n te n t o f th e p e r s p i r a t i o n , X t h in k we s h a l l b e a b le t o s o lv e t h i s Q u estio n by a s a tis fa c to ry tech n iq u e, but up to the p resen t tim e I have been d efeated by our in a b ility to com pletely cleanse the sk in in advance o f th e c o lle c tio n ; o f th e samoles* Single sam ples o f th e p e r s p i r a t i o n o f th e same norm al h e a l t h y J in d iv id u a l have v a r ie d a l l th e way from .07 to .03 m illigram s o f le a d . Under th e co n d itio n s o f our experim ent I f e e l su re th a t t h i s v a r ia tio n is th e result?, of co n tam in atio n of th e sh in r a th e r th an th e r e s u l t o f v a ria tio n in the excretion of lead in the p ersp iratio n A ccordingly I should be very lo a th e to accept the s ig n ific a n c e o f a n a ly tic a l r e s u lts o b tain ed on shin or h a ir , or o th e r appendages of the sk in . viith th e exception of the above c r itic is m ? I have reg ard ed your work w ith a g re a t d eal of in te r e s t and ad m iratio n . I hope you w i l l su p p ly me w ith f u r t h e r r e p r i n t s a s y o u r in v e s tirn tio n s progress. Very truly yours* BAK;is Bobert'iC'lenoe,1:lrT>, K 0019866