The fate of pharmaceuticals, steroid hormones, phytoestrogens, UV-filters and pesticides during MBR treatment

This study examined the relationship between molecular properties and the fate of trace organic contaminants

(TrOCs) in the aqueous and solid phases during wastewater treatment by MBR. A set of 29 TrOCs

was selected to represent pharmaceuticals, steroid hormones, phytoestrogens, UV-filters and pesticides

that occur ubiquitously in municipal wastewater. Both adsorption and biodegradation/transformation

were found responsible for the removal of TrOCs by MBR treatment. A connection between biodegradation

and molecular structure could be observed while adsorption was the dominant removal mechanism

for the hydrophobic (logD > 3.2) compounds. Highly hydrophobic (logD > 3.2) but readily biodegradable

compounds did not accumulate in sludge. In contrast, recalcitrant compounds with a moderate hydrophobicity,

such as carbamazepine, accumulated significantly in the solid phase. The results provide a

framework to predict the removal and fate of TrOCs by MBR treatment.