A large number of phthalate esters were screened for estrogenic activity using a
recombinant yeast screen. a selection of these was also tested for mitogenic effect on
estrogen-responsive human breast cancer cells. A small number of the commercially
available phthalates tested showed extremely weak estrogenic activity. The relative
potencies of these descended in the order butyl benzyl phthalate (BBP)> dibutyl phthalate
(DBP)> diisobutyl phthalate (DIBP)> diethyl phthalate (DEP)> diisiononyl phthalate (DINP)�…