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Data on urinary excretionof tritium hy a 41.year-oltl male who accidentally inhaled (or ingested) tritium, presumed to h e In the form of HTO, a r e presented along wlth an interpretation of these data and an e-timate of the radiation dose delivered to tissue<. JIeasurements of levels in urine were made as long as 255 clays after the intake of the tritium. The data could he represented as a sum of two exponential terms, one with a half-life of about 9 clays, the other of ahout 31 day.:. The total dose t o body water was estlmated to be ahout 16 rem, the long-term esponentlal contributing about 2"b of the total. A two-compartment model was applied to the data. Equations were derived for the amounts of tritium i n each compartment, and an estimate was obtained for the total tloae in a n y tisaue, ha.;ed on a comparinon with the content of hydrogen in the ti;iue. This method of estlmatlng the dose may he applicable for other raclionuclide~ anti compound-. I t assumes the stable element and Its radioactive isotope hehaw similarly, or itlenticallj-, in the hotly, but does not involve assumptions concernunp the mathematical form o f t h e retention function.

It is suggested that an alternative, or additional, source of the blue haze above heavily forested areas may be the generation of submicrometer-sized wax particles by the action of strong electrical fields at the tips of pine needles and other wax-covered plant surfaces. Exposure of pine needles to high potential gradients results in the production of airborne wax particles with diameters less than 0.6 micrometer.

A promising method for making sorption measurements in aerocolloidal systems is described. Initial studies are being conducted on the interaction of sulfur dioxide with metal oxide aerosols. The latter are generated by exploding metal wires in air, resulting in particles with diameters from about 0.01 to 0.1 micron. These are mixed with S33-labeled S02 at controlled conditions in an 820-liter cylindrical chamber. Samples for analysis are withdrawn through diffusion tubes lined with leadperoxide-coated lead foil and followed by membrane filters. Diffusion tube analysis of several S02-aerosol mixtures indicated that this is a possible method of distinguishing between chemisorption and physical adsorption. In measurements that included an adsorption isotherm for S02 on iron oxide aerosol, preferential chemisorption on iron oxide and aluminum oxide was observed at low S02 concentrations and was followed by multilayered physical adsorption at higher concentrations.