ore se ee ee Th1e expe imental appad Bfus for generating the aerosol and exposing the animala'(scc Fig. 1) Was previously described.4® The equipment: congisted of: (1) an aerogh]generator, (2) the animal exposure cham. gl a 2 A generator was design ‘to provide a stream of airborne dry parti cles. at a cqnstant concent tion level (3,2 * 1078 pc/ml).® The rotation of'the outey'tube provide R constant advance of @ brush against theisurBticles. The particles thus agitated werepicked a. jvered to the exposure chamber at a flqwrate . i. ye i ithe prpsent study, Menice were exposedto the dry-particle-fallou! simblant ae manner ide¥ Bical to that used with theionic simulant,4 ‘In ist Faolution can Bing a measured amount of the Sryieimajeet h tube to 36micgy.. dminiter ed by atg ; e animals were SAG; : ced in groups of‘bleach, starting at 3 | hy hrlafte ure and at various:iitervals upto'l5 days, ‘ The experimentalpyOre fostmensuring! hamictivity of the:fisgjonproducts in the ee een described in‘a Bavious report, “ye ¥ he distribution of:i" ae activity was determined in the following oxgans and'tinsues: regulatory tract (starting at the upper end ofthe cornaeote ath aa ber,(3) sample collectorHor collecting particles (for determination.of wee aerosol concenty tion) and (4) supporting equipment (pump,etc. ). a 4 a a a hehe lazynx) and’‘lungs, liverg ibia, thyroid,head,and GJ tract and contents (fram top’Of esophagus: ith: al region), The. autopsies were carried out care to avoid crag p tamination, cs he ‘taspe assays wer@—perforined by determining the gamma activity ‘sodium iodide gang ma scintillation counter. The tissues were ted ig Coors porcelg@ crucibles and positioned under the crystal. ity was not meg gured due to the inherent difficulties with pre»gamples for cqinting. However, previous experiments’have he gamma ac Ayity measurementsipatisfactorily reflectt the -product acti sity. # RESULTS AND “—— Initial Uptake ofthe Iph a : The distribution of the v. * a “a . 3 ay 4 the airborne simulant for 3 hr, and serially a x 4 adioactive fallout simulant in the tissues and e A ‘ : ervsolAnimalTisue organs of mice exposed x u 4