Removal of contaminants of emerging concern (CECs) using a membrane bioreactor (MBR): A short review

Abstract

Contaminants of emerging concern (CECs), such as pharmaceuticals and personal care products (PPCPs) and as endocrine disrupting compounds, have recently recognized as the next set of pollutants due to their toxic effects on human health and aquatic organisms at very low concentrations. One of effective methods to remove these emerging contaminants present in the aquatic environment is a membrane bioreactor (MBR). In this review, 27 CECs belonged to diverse categories of PPCPs were surveyed from the point of view of the removal efficiency by several types of MBR modules with various operational conditions, such as a type of MBR, hydraulic retention time and sludge retention time. As a result, this review provided the overall ranges in the removal efficiency of 27 CECs by different MBR filtrations and modules. Certain categories of PPCPs such as analgesics/anti-inflammatory drugs (acetaminophen and ibuprofen), steroids/hormones (estriol and testosterone) and stimulant (caffeine) have relatively higher removal rates, while antimicrobial agent (TCEP) is rarely removed in the different MBRs. For further implementation of CEC removal by a MBR system, physical characteristics/biological fate of a wide variety of CECs, individual/synergistic effects which may occur during MBR operation, and application of advanced MBR technologies should be studied.