Towards More Sustainable Wastewater Treatment: Consideration of Transformation Products of Organic Chemical Contaminants

Coordinator :

EPOC-LPTC (H. Budzinski)

Active period :

2019-2024

Financing:

ANR

Partners :

INRAE UR REVERSAAL (JM Choubert)

LGC (C. Albasi)

Summary:

Water is a scarce resource whose protection has now become paramount. Preserving its quality is thus essential to both the environment and human health. As such, it is critical to characterize and understand the potentially influential factors, which obviously include chemical contamination, since the outfall ultimately lies in an aquatic medium. The Water Framework Directive (WFD), adopted in Europe in 2000 (2000/60/EC), is intended to protect and/or restore the quality of aquatic ecosystems. In this context, considerable research over the past few years has concentrated on organic micropollutants. The knowledge acquired on their presence, pathways of introduction, sources and impacts on aquatic ecosystems has grown tremendously. Wastewater serves as a major source of micropollutants, in combination with the consumption of manufactured goods. In the aim of protecting the quality of aquatic media, application of the WFD has led to strengthening regulations on urban wastewater treatment and expanding biological processes such as activated sludge with extended aeration or biofilters, thereby making it possible to eliminate a large share of the organic micropollutant load. Oxidation processes are also involved but may lead to incomplete degradation, hence yielding relatively stable and toxic transformation products (TP) capable of winding up in both sludge and liquid effluent. Until now, data on TP has remained hard to find and limited to just a few compounds. It thus seemed relevant for subsequent research projects to focus on the issue of TP in order to determine their presence, formation and fate throughout the wastewater treatment system until potential input into aquatic media via the discharge of treatment plant effluent. The TRANSPRO project lies within this scope, in proposing a study of TP formation that entails developing innovative screening methods through the use of chemical tools (High-Resolution Mass Spectrometry) as well as biological ones (in vitro testing). This project will examine the entire wastewater treatment system (including plant inputs) via natural aquatic ecosystems, with a focus on how the various types of treatment processes correlate with their capacity to generate TP, in conjunction with natural processes (biodegradation, photooxidation), potentially giving rise to transformations within the medium itself. TRANSPRO should serve to improve our state of knowledge on the nature, origin and dynamics of TP. Moreover, it will enable classifying wastewater treatment processes according to their tendency to generate TP, while helping select the most efficient process for degrading parent contaminants and minimizing TP formation.
TRANSPRO is being sponsored by a consortium of public-sector partners; this project is intended to be collaborative through establishing a solid partnership based on multidisciplinary expertise, by associating: analytical chemists (EPOC), physical chemists (EPOC, LGC), environmental chemists (EPOC, Irstea), process engineering and modeling specialists (Irstea, LGC), (eco)toxicologists (EPOC), and wastewater treatment systems specialists (LGC, Irstea). All these professionals have been assembled to address a series of questions spanning multiple disciplines: which processes serve to generate TP, which TP are involved, and which ones are environmentally significant? TRANSPRO will thus provide knowledge capable of enhancing wastewater treatment to advance the design of tomorrow’s sanitation systems.