PFAS in Trégonneau's tap water: 2.3 ng/L, 4.6x our 0.5 ng/L benchmark
Last PFAS check: · Source: Hub'eau
PFAS in drinking water
4.6× above our health benchmark
0.5 ng/L is our benchmark, not an official limit. Same EFSA method as Sweden, Denmark and the Netherlands, but stricter. It's a yearly average, compared here with the latest check.
Sample taken in Cavan, on the same distribution network as Trégonneau (TREGONNEAU). The health authority samples one tap per network; a network carries the same treated water everywhere.
More about this result
The US also limits PFOA and PFOS to 4 ng/L each, per substance.
Substances below the detection limit count as 0, so the real total may be higher.
One of these four, PFOA, is classified as causing cancer in humans by the WHO's cancer research agency (IARC).
More PFAS than in 88% of the cities we track
checked on 26 June 2026
20 PFAS (see each substance)
| PFAS substance | Value |
|---|---|
| Acide perfluorobutanoïque (PFBA) | 0.0018 µg/L |
| Acide sulfonique de perfluorooctane (PFOS) | 0.0012 µg/L |
| Acide perfluoro-octanoïque (PFOA) | 0.0011 µg/L |
| Acide perfluoro tridecane sulfonique (PFTrDS) | <0,001 µg/L |
| Acide perfluoro undecane sulfonique (PFUnDS) | <0,001 µg/L |
| Acide perfluorododécane sulfonique (PFDoDS) | <0,001 µg/L |
| Acide perfluorododécanoique (PFDoDA) | <0,001 µg/L |
| Acide perfluoroheptanoïque (PFHPA) | <0,001 µg/L |
| Acide perfluoro tridecanoique (PFTrDA) | <0,001 µg/L |
| Acide perfluoroheptane sulfonique (PFHpS) | <0,001 µg/L |
| Acide perfluoropentane sulfonique (PFPS) | <0,001 µg/L |
| Acide perfluoro-decanoïque (PFDA) | <0,001 µg/L |
| Acide perfluoro undecanoïque (PFUnA) | <0,001 µg/L |
| Acide perfluoropentanoïque (PFPEA) | <0,001 µg/L |
| Acide perfluorohexanoïque (PFHXA) | <0,001 µg/L |
| Acide perfluoro-nonanoïque (PFNA) | <0,001 µg/L |
| Acide perfluorodecane sulfonique (PFDS) | <0,001 µg/L |
| Acide perfluorononane sulfonique (PFNS) | <0,001 µg/L |
| Acide sulfonique de perfluorobutane (PFBS) | <0,001 µg/L |
| Perfluorohexane sulfonate (PFHXS) | <0,001 µg/L |
Above our health benchmark. Here are some filter options.
- EU legal limit
- 4.1 ng/L sum of 20 PFAS, below the 100 ng/L limit
- Last PFAS test
- 26 June 2026
- Water supplier
- SAUR FRANCE OUEST - BRETAGNE OCCIDENTALE
In Trégonneau, the 4 most closely watched PFAS (PFAS-4) add up to 2.3 ng/L (0.0023 µg/L) at the latest PFAS check on 26 June 2026. That's 4.6 times our 0.5 ng/L health benchmark, but below Sweden's legal limit of 4 ng/L. Sum of 20 PFAS: 4.1 ng/L (0.0041 µg/L), below the EU legal limit (100 ng/L). Sampled in Cavan, on the same network. 3 checks since 1 April 2026: PFAS-4 from 1.7 ng/L to 5.3 ng/L, averaging 3.1 ng/L over 12 months. Falling on the main network. Source: Hub'eau, Qualité de l'eau potable (Ministère de la Santé / OFB / BRGM).
Details and sources
PFAS over time in Trégonneau
3 PFAS checks since 1 April 2026, values as published. Samples from 3 communes on the same network: it's the same water, so each one applies to Trégonneau.
| Date | PFAS-4 | Sum of 20 PFAS | Sampled at |
|---|---|---|---|
| 2.3 ng/L | 4.1 ng/L | Cavan | |
| 1.7 ng/L | 9.1 ng/L | Pédernec | |
| 5.3 ng/L | 5.3 ng/L | Squiffiec |
“<” means not detected, the figure being the detection limit. “–” means not published. Labs have only reported the PFAS-4 sum (SANDRE code 9268) since autumn 2025. How to read a PFAS result
What the latest check found
At the latest check, the water was within every limit tested.
Values to watch
These results are close to their legal limit, or over it.
| What was tested | Value | Limit | Status |
|---|---|---|---|
| Nitrate | 25 mg/L | ≤ 50 mg/L | within the limit |
See all 14 test results
| What was tested | Value | Limit | Status |
|---|---|---|---|
| Nitrate | 25 mg/L | ≤ 50 mg/L | within the limit |
| Nitrite | <0,01 mg/L | ≤ 0.5 mg/L | within the limit |
| Cadmium | <0,025 µg/L | ≤ 5 µg/L | within the limit |
| Chromium | <0,5 µg/L | ≤ 50 µg/L | within the limit |
| Escherichia coli | 0 n/(100mL) | ≤ 0 mL) | within the limit |
| Enterococci | 0 n/(100mL) | ≤ 0 mL) | within the limit |
| Coliform bacteria | 0 n/(100mL) | ≤ 0 mL) | within the limit |
| pH | 8.2 unité pH | 6.5–9 unité pH | within the limit |
| Water hardness | 13 °f | no limit | for reference |
| Electrical conductivity | 380 µS/cm | 200–1,100 µS/cm | within the limit |
| Chloride | 30 mg/L | ≤ 250 mg/L | within the limit |
| Sulphate | 54 mg/L | ≤ 250 mg/L | within the limit |
| Iron | <2,5 µg/L | ≤ 200 µg/L | within the limit |
| Turbidity | <0,1 NFU | ≤ 2 NFU | within the limit |
Frequently asked questions
Is tap water in Trégonneau safe to drink?
Yes. At the check on 17 July 2026, the tap water in Trégonneau was within every limit tested. “Eau d'alimentation conforme aux exigences de qualité en vigueur pour l'ensemble des paramètres mesurés.”
How high are PFAS levels in Trégonneau's drinking water?
The total of 20 PFAS ("forever chemicals") was last measured at 4.1 ng/L. The EU limit is 100 ng/L, so this water is at 4 % of the limit. (below the EU limit)
Does the water in Trégonneau also meet the strictest limits in Europe?
Yes. Even against Europe's strictest legal limit, Sweden's 4 ng/L in force since 2026, the measured value of 2.3 ng/L stays below.
Are PFAS levels rising in Trégonneau's tap water?
No, they are falling. On the main network, the PFAS-4 sum went from 5.3 ng/L (1 April 2026) to 2.3 ng/L (26 June 2026) across 3 quantified checks.
How hard is the water in Trégonneau?
The water hardness in Trégonneau is 13 °f (soft). This mainly matters for household appliances and detergent dosing, not for health.
Where does this data come from?
All values come from official publications: Hub'eau, Qualité de l'eau potable (Ministère de la Santé / OFB / BRGM). Retrieved on 21 September 2026.
Nearby communes
The closest to Trégonneau on this site.
Data source
- Hub'eau, Qualité de l'eau potable (Ministère de la Santé / OFB / BRGM)
- https://hubeau.eaufrance.fr/api/v1/qualite_eau_potable/resultats_dis?code_commune=22358
- License
- Licence Ouverte / Open Licence (Etalab)
- Retrieved
- 21 September 2026
- Supply networks
- TREGONNEAU
Water report for Trégonneau
Get new PFAS results for Trégonneau, with a short explanation. At most one update a week, only when there's something new.
This site is a data project, not an official source. If in doubt, check with your water supplier or local authority.