From occasional questions to systematic monitoring.
SOURCE: EUROPEAN COMMISSION / REVIEWED: 5 OCTOBER 2026
At the start of the rules' application, the European Commission highlighted harmonised PFAS monitoring in drinking water and action when limit values are exceeded. Measures depend on the case and may include additional water treatment or restrictions on the use of a source.
Two different parameters
The Directive sets a value of 0.1 µg/l for “Sum of PFAS” and 0.5 µg/l for “PFAS Total”. These are not two labels for the same measurement: the sum refers to a defined set of compounds, while the broader parameter has a different scope. Countries may use one or both parameters.
Site-specific decisions require checking applicable national requirements, monitoring arrangements and the analytical method used. This introduction does not replace a project-specific or legal assessment.
What does this mean for project preparation?
- Check which compounds and parameters your laboratory report covers.
- Collect data on variations in concentrations and flow rates.
- Define the treatment objective and how performance will be demonstrated.
- Test any proposed additional stage on representative water.
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