Effect of water composition on TiO2 photocatalytic removal of endocrine disrupting compounds (EDCs) and estrogenic activity from secondary effluent

► Ion-TiO2 adsorption inhibits photocatalytic removal of estrogenic activity (EA). ► DOM plays a more important role in inhibiting photocatalytic removal of EA than ions. ► Polar compounds cause a temporary increase in EA during TiO2 photocatalysis. ► Large MW organic matter (>4.5 kDa) inhibits photocatalytic removal of EA.