Action of Tri-Ethylene Melamine in Mice. ∗

Abstract

Summary and Conclusions

Tri-ethylene melamine decreased the total white blood cell counts and the percentage of mononuclear cells. The total white blood cell counts returned to normal between the sixth and tenth days after injection and the mononuclear count returned to normal after one month. The highest percentage of deaths after single injections occurred between the third and sixth days when the total white blood cell counts were lowest. Surviving animals developed a resistance to a second injection, which manifested itself in a long latent period. Nine out of fifteen of the deaths in the latter group occurred between the ninth and thirty-first days, during which period the white blood cell counts were normal. The median lethal dose after a second injection was considerably lower due to the cumulative effect. The toxic effects of tri-ethylene melamine were evidenced in the dramatic fall in white blood cell count and decrease in percentage of mononuclear cells. However, the return to a normal blood picture was no indication that the effects of the drug had been extinguished.