DIETHYLDITHIOCARBAMATE IN TREATMENT OF ACUTE CADMIUM POISONING

Abstract

An insoluble complex was synthesized by the reaction of sodium diethyldithiocarbamate trihydrate (DDTC) with CdCl2.cntdot.2.5 H2O (Cd). Elemental analyses of the product yielded a percent composition of each element which was consistent with the postulated structure of 2 mol equivalents of (DDTC)- and 1 mol equivalent of Cd2+. The DDTC formed a complex with 11 other metal ions tested but not with Ca2+ or Mg2+. The complex with Cd was highly insoluble in water, 0.1 N HCl, 0.1 N NaOH, human serum and CCl4, but it was soluble in pure dimethyl sulfoxide. The DDTC protected mice from a > LD100 dose of Cd. This protective effect was more pronounced when DDTC treatment was delayed at least 30 min after i.p. administration of Cd; > 98% of mice treated with 500 mg/kg DDTC 30 min to 5 h after Cd administration survived and 50% survived when treatment was delayed for 8 h. Administration of DDTC prior to or immediately after Cd gave less protection. The lowest (DDTC)-/Cd2+ molar dose ratio which resulted in 100% survival following the otherwise lethal dose of Cd was 7.6, which was < 4 times the theoretical stoichiometric molar ratio for formation of the complex. LD50 of the complex in mice was .apprx. 650 mg/kg by i.p., which was indicative of a low degree of dissociation in vivo.