Antidotes for zinc intoxication in mice

Sixteen chelating agents were examined to determine their relative efficacy as antidotes in acute zinc acetate intoxication in mice after i.p. administration. For a i.p. dose of 0.49 mmol/kg (LD50) of zinc acetate, the i.p. administration of chelating agents at a 2:1 and 5:1 mole ratio resulted in a significant antidotal action for EDTA, DTPA, CDTA, D-penicillamine (D-PA), DMPS and DMSA. EGTA, L-cysteine, triethylentetraamine (TTHA), N-acetylcysteine (NAC), 4,5-dihydroxi-1,3-benzenedisulfonic acid (Tiron), sodium salicylate, glutathione, sodium diethyldithiocarbamate (DDC), 6-mercaptopurine and N-acetyl-D, L-penicillamine (NAPA) were not effective for acute zinc acetate poisoning. The therapeutic indices and therapeutic effectiveness of the most effective chelators were, respectively: EDTA (5.0, 7.0), DTPA (7.3, 13.7), CDTA (8.6, 6.3), D-PA (4.6, 1.9), DMPS (1.3, 1.0), DMSA (3.2, 5.4). DTPA, CDTA, and EDTA appear to be the most effective agents of those tested in offsetting acute zinc intoxication in mice.