PFAS, often referred to as “forever pollutants,” are not limited to drinking water, soils, or food. A study by Surfrider Foundation Europe and Eurofins shows they are also present in swimming waters, along the coast, in lakes, and in rivers. The topic is worrisome because these substances are highly persistent, mobile, hard to eliminate, and linked to environmental and human health risks.
PFAS: why these forever pollutants worry swimming waters
PFAS form a broad family of synthetic chemical compounds used across many industrial sectors and consumer products. Their main problem is persistence: once released into the environment, they break down very slowly. The report notes that these substances spread in water, soils, and air, with possible exposure routes by ingestion, inhalation, or skin contact.
Until now, PFAS were mainly discussed in relation to drinking water or food. The value of this study is to open another angle: beaches, aquatic facilities, rivers, and recreational water zones. These places are frequently visited by bathers, surfers, kayakers, children, walkers and residents who often view them as natural spaces that are relatively protected.
The central finding is straightforward: PFAS are widely present. The report shows PFAS were detected at all sites studied, though levels vary greatly from one location to another. An important point: a beach that is labeled as “less polluted” in the ranking does not mean a PFAS-free beach, but a beach where the measured load is lower according to the indicators used.
One of the most striking results concerns TFA, a molecule in the PFAS family. It is found in 100% of samples, with an average of 707 ng/L, and concentrations ranging from 180 ng/L to 5,800 ng/L depending on sites. This illustrates the scale of diffuse contamination: it is not a handful of isolated hotspots, but widespread presence. The study is based on a sampling campaign conducted between June and July 2025: 107 sites were tested, including 80 coastal sites and 27 lacustrine or riverine sites, in metropolitan and overseas France. In total, 58 PFAS and derivatives were searched for, with more than 6,200 results analyzed.
What the data show: PFOS, threshold exceedances and highly variable contamination
To understand the results, two indicators must be distinguished.
The first is PFOS, one of the most well-known and monitored PFAS. In the report, it is compared to the environmental quality standards under the Water Framework Directive: 0.65 ng/L for freshwater and 0.13 ng/L for coastal waters. When these thresholds are exceeded, the site is considered “non-conforming” in the study.
On this indicator, exceedances are numerous: the report states that the maximum authorized PFOS values are exceeded at 78% of continental sites and 44% of coastal sites tested. It’s a strong signal, because PFOS is already subject to restrictions, but it remains present at significant levels.
The second indicator, more global, is the ΣPEQ, or cumulative toxic equivalent. It adds together the concentrations of several PFAS while taking into account their relative toxicity. In other words, it aims to provide a fuller picture than PFOS alone. The report explains that each concentration is multiplied by a relative toxicity factor, then compared to a guide value of 280 ng/L used by Dutch authorities for surface waters.
Using this method, a site far exceeds the guideline value: the Bedane nautical base, in Seine-Maritime, with 450,161 ng/L. This isn’t a beach in the strict sense, so it does not appear in the beach rankings below, but it is the most concerning site in the entire study for the ΣPEQ indicator.
The report also highlights a significant gap: there is currently no harmonized European framework for monitoring or managing PFAS in swimming waters. This means that the data produced here serve both to alert and to fill a knowledge gap.
Top 5 beaches most and least polluted by PFAS
For this ranking, I include sites explicitly named “beach” or “plagette” in the report, and I classify them according to the ΣPEQ indicator, which is more global than PFOS alone. Values are expressed in ng/L, nanograms per liter. A nanogram is an extremely small amount, but for persistent substances like PFAS, the seemingly modest numbers should not obscure the issue of accumulation and repeated exposure.
Top 5 beaches most polluted according to ΣPEQ
| Rank | Beach / Site | Region | ΣPEQ | PFOS | No. of PFAS |
|---|---|---|---|---|---|
| 1 | Baraka Beach, Miribel Lake, Neyron | Rhône | 53,820 | 13 | 14 |
| 2 | Ispe-Navarosse Beach, Biscarrosse Lake | Landes | 22,515 | 1.8 | 11 |
| 3 | Bléré Beach | Indre-et-Loire | 19,292 | 2.9 | 13 |
| 4 | Courant Beach, Mimizan | Landes | 18,876 | 4.1 | 12 |
| 5 | Joinville Beach – Sandbank | Val-de-Marne | 14,144 | 2.3 | 15 |
The top three beaches in this ranking are freshwater or similar sites, where ΣPEQ levels are among the highest: Baraka Beach, Ispe-Navarosse, and Bléré Beach appear in the freshwater sites table. Courant Beach in Mimizan appears among coastal sites with 18,876 ng/L.
Top 5 beaches least polluted according to the ΣPEQ
| Rank | Beach / Site | Region | ΣPEQ | PFOS | No. of PFAS |
|---|---|---|---|---|---|
| 1 | La Torche Beach, Plomeur | Finistère | 0.36 | <0.10 | 1 |
| 2 | Le Porge Beach | Gironde | 0.38 | <0.10 | 1 |
| 3 | Salée Bananier Beach, Capesterre-Belle-Eau | Guadeloupe | 0.40 | <0.10 | 1 |
| 4 | Montiers Beach, Erquy | Côtes-d’Armor | 0.48 | <0.10 | 1 |
| 5 | Lacanau Beach | Gironde | 0.48 | <0.10 | 2 |
These beaches are among the sites with the lowest ΣPEQ values. La Torche, Montiers, and several Brittany beaches rank among the lowest coastal values, while Le Porge and Lacanau also show low levels. Salée Bananier Beach in Guadeloupe is also among the lowest with 0.40 ng/L.
This ranking should not be read as a swimming ban, as the report does not establish an official health ranking of beaches. It highlights an environmental reality: PFAS are present throughout the sampled area, but with very different intensities. The sites with the highest levels call for further investigations, identification of pollution sources, and ongoing monitoring over time.
