Toxicity of cadmium administration to the toad and the treatment of its poisoning with EDTA

Abstract

1. 1. The effect of cadmium administration on female Bufo regularis was studied. The median lethal doses were 22, 18, 15 and 6.2 Cd 2+/kg after 24, 48, 72 and 96 hr respectively. 2. 2. After a single intramuscular injection of 6.2 Cd 2+/kg (representing 96-hr ld 50), the results indicated that Cd 2+ causes severe physiological abnormalities to this experimental animal. 3. 3. The serums alanine aminotransferase (AlAt), aspartate aminotransferase (AAt), alkaline phosphatase (A1P) and lactic dehydrogenase (LDH) were elevated while the calcium serum was not influenced by Cd 2+ throughout the experimental period 4. 4. On the other hand, phosphorus, total protein and total bilirubin were increased. 5. 5. EDTA treatment (0.2 mmole/kg protected female toads from mortality up to 20 mg Cd 2+/kg. It overcame the physiological alterations that were caused by the Cd 2+ injection. 6. 6. This may be due to the fact that Cd 2+ is bound to EDTA in a strong complex which is readily excreted via the kidneys.