Emerging contaminants in wastewater: The new challenge for Europe’s water management
Europe is undergoing a profound transformation in the way it manages water. Over the past decade, extreme droughts, increasing pressure on water resources, and the need to safeguard long-term water security have pushed policymakers to update the legislative framework for wastewater treatment, water reuse, and the control of emerging contaminants.
The result is a far more stringent regulatory environment—one that not only defines the quality requirements for reclaimed water but also drives systematic monitoring and mitigation of substances that, until recently, were outside the scope of routine control.
A new era of water reuse: Regulation (EU) 2020/741
Since becoming fully applicable in June 2023, Regulation (EU) 2020/741 has set the minimum requirements for using reclaimed water in agricultural irrigation. It defines obligations for operators, establishes audit and risk-management procedures, and sets microbiological quality criteria.
This Regulation is tightly aligned with the Water Framework Directive, EU food and hygiene legislation, and the updated Urban Wastewater Treatment Directive (UWWTD)—a major reform now being rolled out progressively until 2040.
What’s new in the Urban Wastewater Treatment Directive (UWWTD)?
The revised UWWTD marks a major shift toward more advanced, sustainable, and health-protective wastewater treatment systems. Its key elements include:
1. Advanced treatment processes
Mandatory tertiary and quaternary treatments aim to remove microcontaminants that conventional systems cannot address.
2. Systematic monitoring of emerging contaminants
This includes PFAS, microplastics, and several categories of pharmaceuticals—substances increasingly detected at trace levels in wastewater.
3. Tighter nutrient controls
Large urban areas must reduce nutrient pollution more aggressively to protect rivers, lakes, and coastal zones.
4. Extended Producer Responsibility
Sectors such as pharmaceuticals and cosmetics must contribute financially to removing the contaminants they introduce into wastewater systems.
5. Climate and energy requirements
The directive moves treatment plants toward net-zero emissions, integrating energy efficiency and greenhouse-gas reductions.
Together, these measures strengthen the link between wastewater treatment, safe water reuse, and aquatic ecosystem protection.
Why emerging contaminants matter
Emerging contaminants (ECs) are compounds that may pose risks to human health or the environment and typically appear at ultra-trace levels (ng/L–µg/L). Their growing relevance comes from:
- their persistence,
- their bioactivity,
- and their widespread use in consumer and industrial products.
The decision to require systematic monitoring reflects their increasing priority across Europe.
The most relevant groups of emerging contaminants
- Pharmaceuticals and metabolites
- Personal care and cosmetic products
- PFAS (per- and polyfluoroalkyl substances)
- Microplastics and nanoplastics
- New-generation pesticides
- Antibiotics and antimicrobial resistance genes
How we monitor and treat emerging contaminants
Accurate monitoring in wastewater—a highly complex matrix—requires specialised extraction methods and advanced analytical technologies. Among them:
- Py-GC/MS, ideal for detecting polymeric contaminants such as microplastics.
- LC-QTOF, a high-resolution technique for identifying and quantifying pharmaceuticals, PFAS, and other organic microcontaminants.
Advanced treatment technologies
To meet the new quaternary treatment requirements, research is evolving toward hybrid solutions that combine established tertiary technologies with emerging ones:
- Activated carbon
- Ozonation
- Chlorination
- Selective membrane processes
- Photocatalysis
These combinations aim to significantly reduce the load of persistent contaminants before water is released or reused.
The role of bioassays in risk assessment
Analytical results alone do not fully explain potential impacts on health or ecosystems. In vitro bioassays help bridge that gap by evaluating:
• ecotoxicity effects,
• cell viability changes,
• and disruptions to key physiological functions.
This biological perspective is essential when contaminants in wastewater may ultimately reach the environment or even the food chain.
Towards safer and more sustainable water use
The EU’s evolving regulatory framework reflects a clear message: managing emerging contaminants is central to the future of water protection and reuse. As requirements become more rigorous, adopting advanced monitoring and treatment solutions will be crucial to ensure safe, circular, and sustainable water systems.
If you need more information on this topic, contact AIMPLAS.
