Determination of the Occurrence and Elimination of Endocrine Disrupting Compounds (EDCs) in Municipal Wastewater Treatment Plants (WWTP)

Claudia Lange,Joerg W Metzger,Bertram Kuch

doi:10.4236/cweee.2014.31001

Abstract

In recent years, many research and development activities have focussed on endocrine disrupting compounds (EDCs) in rivers, lakes and surface waters as the potential cause of reproductive disturbances in different aquatic organisms e.g. fish and mollusk. The effluent of wastewater treatment plants was identified as main source for EDCs entering the aquatic environment. The purpose of the present study was to determine the estrogenic activity of wastewater and the elimination efficiency of various WWTPs in the different purification steps using the E-screen assay, an in-vitro test system based on the increasing proliferation of human breast cancer cells (MCF-7) in response to the presence of hormonal active substances. In contrast to expensive and time-intensive targeted instrumental single substance analysis an effect-related biological testing provides a sum parameter for the entirety of compounds contributing to the total estrogenic activity (agonists and antagonists, anti-estrogenic and also toxic compounds) in concentration units of the reference substance 17b-estradiol. The current standard purification methods of biological wastewater treatment in particular the activated sludge process significantly reduce estrogenicity (average 95%). Sorption on activated carbon and subsequent precipitation leads to a further reduction of the overall estrogenic activity up to 99%.

Highlights

The water quality of rivers and lakes in Germany, which had deteriorated rapidly due to the economic and industrial development after the war, could be greatly improved by the widespread construction of treatment plants, especially in the beginning of the 1970s
To examine whether advanced purification techniques have an influence on the elimination efficiency of endocrine disrupting compounds (EDCs) two wastewater treatment plants (WWTP) (WWTP2 and WWTP3 with population equivalents (PE) of 150,000 and 57,200), which use the adsorption flocculation filtration process (AFF) as an additional purification step for several decades, were investigated
It becomes apparent that the current standard purification methods of biological wastewater treatment, especially the activated sludge process significantly reduce estrogenicity

Summary

Introduction

The water quality of rivers and lakes in Germany, which had deteriorated rapidly due to the economic and industrial development after the war, could be greatly improved by the widespread construction of treatment plants, especially in the beginning of the 1970s. In recent years research and development activities have focussed on micropollutants in lakes and rivers. Since the effluent of municipal wastewater treatment plants (WWTP) is one main source for EDCs in the aquatic environment, their fate, transport and biodegradation during WWTP has become a subject of intense research. Despite removal efficiencies in the range of >95% (for synthetic and natural hormones) during conventional biological treatment steps, the concentrations in receiving waters reach low ng/L-levels which are known to affect aquatic organisms. With regard to this aspect the efficiency and optimization of conventional treatment

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