Advocate General Kokott’s Opinion in Case C-193/25(Poland v Parliament and Council)
Implications for the UWWTD Extended Producer Responsibility Framework
Executive Summary
The Advocate General proposes the annulment of the provisions requiring pharmaceutical and cosmetics producers to finance at least 80% of the costs associated with quaternary wastewater treatment. Importantly, the Opinion does not challenge the environmental objectives of the Directive, the need to reduce micropollutants in wastewater, nor the legitimacy of introducing quaternary treatment. Instead, it focuses on the scientific and evidentiary basis underpinning the allocation of financial responsibility.
According to the Opinion, the EU legislature failed to demonstrate with sufficient scientific rigour, transparency and justification that pharmaceuticals and cosmetics alone are responsible for a share of micropollutants that warrants bearing 80% of the costs associated with advanced treatment.
→ Link to the Opinion: Advocate General Kokott Opinion – Case C‑193/25
Background and regulatory context
Directive (EU) 2024/3019 (Urban Waste Water Treatment Directive, UWWTD) introduces a new level of treatment aimed at removing micropollutants from urban wastewater. This so-called quaternary treatment represents one of the most ambitious measures adopted by the European Union to address contaminants that are not adequately removed through conventional wastewater treatment processes.
To finance these additional investments and operating costs, Article 9 establishes an Extended Producer Responsibility (EPR) scheme requiring producers placing pharmaceutical and cosmetic products on the EU market to cover at least 80% of the costs related to quaternary treatment, monitoring activities and administrative management of the system.
Poland challenged these provisions before the Court of Justice of the European Union, arguing that the allocation of costs was unsupported by the available scientific evidence and therefore infringed several fundamental principles of EU law, notably proportionality, equal treatment and the polluter-pays principle.
The core legal question before the court
A key aspect of the Opinion is that it does not question the environmental necessity of addressing micropollutants.
The dispute is not whether micropollutants pose environmental risks, nor whether advanced wastewater treatment is justified. It is also not a debate about whether producers may be required to contribute financially to pollution control measures.
Instead, the central legal issue concerns the evidentiary link between pollution and financial responsibility.
Can the EU legislature legitimately impose a mandatory financing obligation representing at least 80% of treatment costs on two industrial sectors without demonstrating convincingly that they are indeed responsible for a comparable share of the environmental burden?
For the Advocate General, the answer depends on the quality, transparency and robustness of the scientific evidence used during the legislative process.
Scrutiny of the scientific evidence
The European Commission largely relied on studies indicating that pharmaceuticals and cosmetics contribute:
73% of micropollutant loads entering wastewater treatment plants;
65% of toxicity-weighted pollutant loads based on chronic toxicity indicators;
up to 92% of toxicity when assessed using PNEC-weighted approaches.
These figures became central to the legislative justification for assigning 80% of treatment costs to these sectors.
However, the Opinion notes that the underlying studies, while influential, were not always accompanied by sufficiently detailed explanations of the methodological choices driving those conclusions.
The criticism is therefore less about the numerical results themselves than about the transparency and reproducibility of the analyses used to generate them.
In essence, the Advocate General appears to be asking whether the institutions adequately demonstrated why the selected approach was the most appropriate scientific basis for major regulatory decisions involving billions of euros of future investments and operational costs.
Concerns regarding the pharmaceutical sector
One of the most significant observations concerns the pharmaceutical industry's attributed contribution to wastewater toxicity.
The Opinion highlights that a very limited number of pharmaceutical substances appear to account for a disproportionately large share of the calculated toxicity burden. In certain assessments, four active pharmaceutical ingredients reportedly represent more than half of the sector's overall contribution.
The Advocate General notes that alternative ecotoxicological values available in recognised scientific sources could substantially alter these calculations. Depending on the selected Predicted No Effect Concentration (PNEC) values, the estimated contribution of pharmaceuticals to overall toxicity could decrease considerably.
This observation is particularly important because it raises questions about the sensitivity of the legislative conclusions to methodological assumptions. If relatively small modifications to a few parameters significantly change the outcome, the robustness of assigning fixed cost shares to entire sectors becomes more difficult to justify.
Concerns regarding the cosmetics sector
The Opinion raises similar concerns regarding the cosmetics industry.
Particular attention is given to substances such as permethrin and certain fatty acids, which may be present in cosmetic formulations but also originate from numerous other industrial, agricultural or consumer uses.
The Advocate General considers that the legislative documentation does not sufficiently demonstrate that the environmental presence of these substances can predominantly be attributed to cosmetic products.
This issue is especially relevant because EPR systems fundamentally rely on establishing a credible causal relationship between the producer category and the environmental impact being addressed.
Without a clear attribution mechanism, the legitimacy of assigning substantial financial obligations to a specific sector may be weakened.
Potential underestimation of other sources of micropollutants
A recurring theme throughout the Opinion is the possibility that other sectors contribute more significantly to micropollutants in wastewater rather than reflected in the legislative framework.
The Advocate General refers to evidence suggesting potentially relevant contributions from:
pesticides;
biocidal products;
plastic additives.
The criticism is not necessarily that these sectors should automatically be included in the EPR scheme. Rather, it is that the legislative process does not sufficiently explain why they were excluded while pharmaceuticals and cosmetics were singled out as the principal contributors.
This aspect could have broader implications for future environmental legislation. The Opinion appears to signal that sector-specific financial obligations must be supported by a transparent and comparative assessment of all significant pollution sources, not merely selected categories.
A strict interpretation of the polluter-pays principle
The Opinion offers an important interpretation of the polluter-pays principle.
Rather than viewing the principle simply as a basis for imposing environmental costs on industry, the Advocate General emphasizes that it also establishes limits. Financial obligations must remain proportionate to the actual contribution of each sector to the pollution being addressed.
In this respect, the Opinion links scientific evidence, proportionality and equal treatment into a closely interconnected legal framework.
A polluter-pays system based on insufficiently supported assumptions risks undermining the very principle it seeks to implement.
This reasoning may prove influential beyond the wastewater sector, particularly as the European Union increasingly relies on producer responsibility schemes to finance environmental objectives.
Arguments rejected by the Advocate General
Despite her criticism of the EPR cost-allocation mechanism, the Advocate General rejects several other arguments put forward by Poland.
The Opinion considers that:
the legislature enjoyed a broad margin of discretion regarding the estimation of quaternary treatment costs;
uncertainties surrounding future implementation costs do not by themselves invalidate the Directive;
concerns regarding generic medicines manufacturers were insufficient to justify annulment;
the exemption mechanisms included in the Directive are not inherently unlawful.
Consequently, the proposed annulment remains narrowly focused on the evidentiary basis used to justify the allocation of costs between economic sectors.
Implications for industry
Pharmaceutical sector
Should the Court ultimately follow the Advocate General's reasoning, pharmaceutical companies could see the current 80% contribution mechanism annulled.
However, this should not be interpreted as an exemption from future responsibility.
A revised framework could still impose substantial obligations on pharmaceutical manufacturers, albeit under a methodology that more clearly demonstrates sectoral contributions to micropollutants in wastewater and potentially distributes costs across a larger number of sectors.
Cosmetics sector
For the cosmetics industry, the Opinion may be viewed as recognition of concerns repeatedly raised during the legislative process regarding the attribution of environmental impacts.
Future legislative revisions may require more substance-specific assessments, improved source apportionment methodologies and clearer differentiation between cosmetic sources and other pathways contributing to environmental contamination.
Strategic outlook for UWWTD implementation
Should the Court follow the Advocate General, the European Commission would likely need to revisit the scientific framework underlying EPR, reassess sectoral contributions to micropollutants and provide more transparent documentation supporting future legislation. Additional sectors such as pesticides, biocides or plastic additives could become part of future discussions on cost allocation.
Conclusion
Advocate General Kokott's Opinion represents one of the most significant legal developments affecting the implementation of the revised UWWTD since its adoption.
The Opinion does not question the environmental necessity of reducing micropollutants, nor does it challenge the principle of Extended Producer Responsibility as a policy instrument. Instead, it focuses on a more fundamental question: whether the allocation of financial responsibility is supported by sufficiently robust and transparent scientific evidence.
Its central message is clear. Before assigning billions of euros of wastewater treatment costs to specific industries, the European Union must be able to demonstrate, with a high level of scientific credibility and methodological transparency, that those industries are genuinely responsible for the share of pollution attributed to them.
Regardless of the final judgment, the case is likely to influence not only the future implementation of the UWWTD but also the design of future EPR systems across Europe, reinforcing the need for strong scientific foundations whenever environmental responsibilities are translated into economic obligations.
Author: Cyril Durou
