The acute oral LD50 of Endrin is in the range of 3 mg/kg body weight in monkeys to 36 mg/kg in guinea pigs.

Endrin inhibits adipocyte differentiation by selectively altering expression pattern of CCAAT/enhancer binding protein-alpha in 3T3-L1 cells. Endrin's inhibitory effect was effective only when the pesticide was present in the medium during the first 48 h after exposure of 3T3-L1 cells to adipogenic inducers. Immunoblots analysis revealed that endrin caused a dose-dependent, selective inhibition of the intracellular levels of CCAAT enhancer binding protein (C/EBP)alpha without altering the expression patterns of C/EBPbeta or C/EBPdelta along the differentiation. Endrin inhibited the normal decrease in nuclear factor-kappaB-DNA binding observed as cells are acquiring the adipocyte phenotype at a late stage of differentiation. It was suggested that endrin inhibits adipocyte differentiation through the specific suppression of C/EBPalpha.