Endocrine Disruptors in Water: An Invisible but Very Real Threat

A Generally Safe Water Supply, but Alarming Signals Are Multiplying

Tap water in France remains one of the most tightly controlled consumer products: more than sixty regulated parameters, regular analyses, and constant oversight by regional health agencies. In 2022, over 84% of French citizens consumed compliant water throughout the year. But behind this apparent stability, another reality is emerging: the growing presence of invisible pollutants linked to pesticides, metabolites, PFAS, and hormonal residues. In 2025, according to several independent investigations, nearly one quarter of the French population was exposed at least once to water exceeding regulatory limits for one or more of these contaminants. (“Qualité de l'eau potable,” French Ministry of Health, December 2024.)

Pesticides and Metabolites: The Overlooked Pollutants

While “classic” pesticides are already subject to strict monitoring, their degradation products—known as metabolites, often escape surveillance. Of the 79 metabolites identified by health authorities, only 23 are currently tested for on a routine basis. Molecules such as DIPA or TFA (trifluoroacetic acid), often resulting from herbicide breakdown, persist in the environment and find their way into groundwater. Some of these compounds are suspected endocrine disruptors, capable of interfering with human and animal hormonal systems even at extremely low concentrations. (ANSES Report, “PFAS: Toward Broader Monitoring,” December 2024.)

PFAS: The “Forever Chemicals” Now Flowing from the Tap

PFAS, chemical compounds used for their non-stick and water-repellent properties, are now omnipresent in air, soil, and water. Their extreme stability makes them a nightmare for current treatment systems. In early 2025, a survey conducted by UFC-Que Choisir and Générations Futures revealed the presence of PFAS in 96% of water samples analyzed across 30 French municipalities. TFA, one of the smallest of these compounds and derived from certain pesticides, reached striking concentrations:

• up to 13,000 ng/L in Moussac (Gard)

• 6,200 ng/L in Paris

• 2,700 ng/L in Nantes

These levels far exceed the European quality limit of 100 ng/L for the sum of 20 regulated PFAS. (“Polluants éternels dans l'eau du robinet,” UFC-Que Choisir / Générations Futures, January 2025.)

When Pollution Forces Restrictions

On April 25, 2025, the Haut-Rhin Prefecture took an unprecedented measure: restricting the use of drinking water for sensitive populations in 11 municipalities of the Saint-Louis metropolitan area, due to persistent PFAS limit exceedances. Pregnant women, infants, and immunocompromised individuals were advised to avoid consuming tap water. The contamination, traced back to the historical use of firefighting foams at the airport site, illustrates the difficulty of removing these compounds even with modern infrastructure. Mobile activated-carbon treatment units are being installed while permanent treatment plants are scheduled for 2027. (“Restriction de l’usage de l’eau potable dans l’agglo de Saint-Louis,” Prefecture of Haut-Rhin, April 25, 2025.)

Hormones and Endocrine Disruptors: A Silent Contamination

Hormones originating from contraceptive pills or hormone therapies are only partially removed by wastewater treatment plants. A fraction persists in aquatic environments and can reappear, at trace levels, in drinking water. Although concentrations are extremely low, their cumulative effect and biological activity raise concerns about fertility, growth, and development in living organisms. These micropollutants do not trigger acute alerts but contribute to a chronic, poorly understood contamination.(“L'eau du robinet est-elle potable ?” Nutritionniste-Paris, July 30, 2025.)

From Reaction to Prevention: Rethinking Monitoring

These situations, from TFA contamination to the Saint-Louis crisis, reveal the limits of the current model, based on occasional sampling and thresholds defined after the fact. Responsiveness is now crucial: detecting early, understanding changes, and acting before non-compliance occurs. In this context, technological innovation plays a key role. (Ouest-France, “Eau potable contaminée : quelles sont les villes concernées ?” January 22, 2025.)

Focus – Klearia’s PANDa+: Smart, Continuous Monitoring

Developed by Klearia, PANDa+ is a real-time monitoring instrument capable of continuously measuring and tracking micropollutants in water. Thanks to its patented microfluidic technology, PANDa+ anticipates quality deviations and rapidly detects contamination events. Connected and modular, it integrates seamlessly into both distribution networks and treatment plant outlets. Recording data (time, intensity, hydraulic conditions), provides complete traceability and helps operators optimize control plans and corrective actions.

Endocrine disruptors, whether from pesticides, PFAS, or hormones, challenge our ability to preserve water quality against diffuse and persistent contaminants. Their monitoring can no longer rely on occasional campaigns: it must become continuous, connected, and intelligent. With tools like PANDa+, water management shifts from a reactive stance to a culture of prevention, essential for ensuring safer, more sustainable, and transparent water.