Document 3NZqGyOZmkOvY97Vwv8ENXe8D

us of Human Umd Inhalation iispQ^tsam.t as of February 19% nubfact I who- two years {? hours/day) In the chamber xpoe4 to0?*> ng/ load seaquioxi&e* *0$ micron median diameter* has now boon out of this chamber a little over 1 year* owing which t*..Xn he ha continued under observation* except for a short vaction^-tasSMBU It appears that ho has oxcretod the load which !iM boon accumulated dtsrtng bis exposure* but it is necessary to follow hi intake of- lead .In- food and beverages end Ms output 1st the feces end urine for sees additional months '.ofor thi can bo established unocuivocaH:/ -'.subject IX is still in tha chamber end so far has boost eapesed C? Xioura/day) for XI? years to 15> mg/.' lead seseuioxldS .05 micron median dismetor* It is oppft rent that he has almost* cut perhaps not -quite, roeclied on fjuilibrim with respect to his intake end output of load* ?>t a point where the total quantity of load retained in Ms body during the aqperixKmt is $sst obeut twice that retained by Subject X during the a&m opprexiaato period of time* i bom montlis of additional tine in ihe chamber will bo ncooeoary to establish the facts with rlepeot to till o"uilibrim* ' Further PxporirKmfcg Plans are being mode* equipment .1 being oscaaabXod* end preliminary tests re in pva-$riv&m to provide a controllable eononfcrntiatt of lead aeslbS of larger rsadian sii'Q than 2tcs heretofore been used in is? xporimenfc* It is possible that this oxperimnfc can be carried out under conditions Which sisjalsfce mro nearly the physical (and ohoaicel) state of the lead in the exhaust of the automobile* not tljat remise to bo soon* A further exporinont# will call for a suitable oxperistan&al aub^eet* 2t has been believed until very rocontly that Subject X could be need ggain in this axporlmsnfc* St- in possible that this my bo found to bo imdoelr&ble* If this is no deoided# a e w subject will bo found and used In prollninary observations in preparation .for this experiaenfc* The preliiairiapy abe or rations will not mod to bo <n to a 0 tuxtensive HTstl pro* longed es those carried out iJ the b two o?cper&ment In any case* no prolonged del* - wil.1 bo involvod, cine the observations on both SubJ* .4* 'V T < and ftxb^oet II will bo continued for sosae months longer* 0020837