Effects o f Combined Treatm ent with Diethyldithiocarbam ate and Diethylenetriam inepentaacetate on Organ Distribution and Excretion

D iethyld ith iocarbam ate (DDTC) and d ie thy lenetriam inepen taace ta te (DTPA) w ere assessed to determ ine if combination treatm ent with these two chelators of different chemical classes would enhance mobilization and excretion of m etallothionein-bound cadmium (Cd) from selected organs of m ice w hich had e a rlie r rece iv ed 0 .03 mg of C dC l2'2 .5 H 20 along with 1.0 (xCi of 109Cd. In addition to measuring individual organ radioac­ tivity after seven and after 13 injections of each com pound individually as well as in combination, whole body Cd burden was m easured, and the routes and rates of Cd excretion w ere determ ined. W hen used alone, D DTC was effective in mobilizing Cd from kidney, liver, intestine, and spleen. The DTPA w hen used alone was not consistently effective in re ­ ducing Cd burdens in any of the organs assessed. Coadministration of D DTC and DTPA prom oted an enhancem ent of Cd mobilization from liver, kidney, spleen, and intestine over that which was observed with D DTC alone. W hen DTPA was adm inistered with DDTC, it did not p re ­ vent accumulation of Cd in lung and brain which was observed upon treatm ent with DDTC alone. Com bined treatm ent did produce a more m arked depletion of total body 109Cd burden than did the administration of D D TC alone. A more rapid rate of both fecal and urinary excretion of Cd was observed w hen the chelators w ere coadministered. It was con­ cluded that at least an additive or possibly supraadditive effect may be obtained by combining a dithiocarbam ate chelator with one of the aminocarboxylate class in total body Cd decorporation. * Supported by the Veterans Administration and by VA-NCI Interagency Agreement IGA V101 (134A)P77014.