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1. lODOACETATE AND lODOAt'ETAMIDE 



Table 1-39 

 Toxic and Lethal Doses of Iodoacetate 



" In most cases the dosage refers to iodoacetic acid rather than to a salt, but in 

 some it is impossible to determine exactly the weight basis. 



acetate is somewhat less toxic. The resistance to iodoacetate apparently 

 varies with the age, since newborn mice can survive as much as 500 mg/kg 

 subcutaneously, whereas the adult LD50 is 75 mg/kg (Fitzgerald, 1955). 

 Since iodoacetate acts essentially irreversibly it can exert its effects for a 

 long time, so that even small doses may be lethal after a prolonged interval. 

 Hall and Field (1932) studied the relationship between intraperitoneal dose 

 in rats and survival time, and found that at doses of 130 mg/kg or above 

 the time for 50% survival is 10 min or somewhat less; most of this delay 

 is due to the time for absorption. When the dose falls below 90 mg/kg, 

 the survival time become rapidly longer, so that at 70 mg/kg it is 150 min, 

 and at 50 mg/kg all rats survive at least 24 hr. 



