- 40 ‘ Manhattan workers resulted from aspiration of droplets of liquid solutions of plutonium into the air wherein much larger particle sizes would result. At the same time, the activity of the plutonium in the particle would be considerably less than that for a particle of Pu0 2. - For example, it is stated that 14 of the 25 subjects with measurable body'burdens of ’ plutonium worked in the recovery operation and that this eccurred when working with solutions containing 1-40 g/liter of plutonyl nit trate to which H20> was being added with vigorous stirring in an open hood. This resulted in con- siderable fizzing and the discharge of droplets into the air outside the hood, A droplet 1 u in diameter (0.5 uw) from the solution with the highest concentration (40 g/liter) would therefore contain only 6x1074 pci compared with a 0.07 pCi particle of Pul2 nm (a specific activity that is lower by’a factor of 100). 7? In other words, the particles involved in this study do not qualify as hot particles. _ They are delivering dosages lower than 1000 rem/yr to the 1/ Recall Erom Table IV that a 0.07 pCi, the limiting activity for a hot particle, would give @2 dese of 1000 renm/vr to the surrounding tissue in a lung inflated to 1/2 maximun. 72/ Of the particles of an inhaled acrosol that are depcsited Jess than 5 u in diameter virtually ail cre On.ee: A 5 u droplet from the 40 g/liter solution would ccorre roughly to the limiting activity of a hot ourticls, D. ‘5 on MORL=5O387, t [Geesanman, OO in the deep respiratory zone of the lung,