and produces an increase predominantly in fecal iron excretion after a single oral dose, only 6% of iron excretion accruing in the urine (Table 3). It is highly selective for iron, is rapidly absorbed, and circulates for several hours. In the non-iron-loaded marmoset and rat, its main toxic effect was on the renal tubular epithelial cell, but this effect was abrogated in iron-loaded marmosets and substantially reduced in iron-loaded rats.