摘要：Oral LD50 values (at 24- and 168-hr) for eight metal salts were determined in female ICR mice pretreated orally with small doses (1/10 of the challenge doses) of the same metal ions or with deionized water at 24hr prior to the challenge doses. The LD50 values for Cd2+ or Mn2+ increased with pretreatment by the same ion, but those for Hg2+ decreased. Pretreatment with Cu2+, Fe2+, Fe3+, Pb2+ or Zn2+ had little effect on the lethality of the same ion. Cd2+ pretreatment was the most effective in reducing the acute toxicity of the same ion. Pretreatment with Cu2+ Hg2+ or Zn2+ protected mice against the toxic action of Cd2+.
