Behavior of I131 Following its Inhalation as a Vapor and as a Particle

Abstract

The behavior of I/sup 131/ in mice following its inhalation as a vapor and as an insoluble particle, AgI, is described. About 70 per cent of inhaled I/ sup 131/ and only 12 per cent of inhaled Ag/sup 131/ particles were deposited. In both cases I/sup 131/ was rapidly transferred from the initial sites of deposition to thc circulatory system as evidenced by rapid appearance of I0a0 in other tissues. After 20 to 30 hours maximum thyroid uptake was observed, 2.5 per cent of total I/sup 131/ vapor inhaled and 1.6 per cent of total inhaled as Ag/sup 131/. After inhalation of both soluble I/sup 131/ vapor and insoluble Ag/ sup 131/ particles about 60 per cent of the total body burden of I/sup 131/ was present in thyroid. The authors do not recommend changes in presently established MPC/sub /air/) values for I/sup 131/ but do not point out the possible pitfalls of basing an MPC calculation on the solubility of a compound in pure substances instead of in tissue fluids. (auth)