PFAS in Guern's tap water: under 3 ng/L, none of the four main PFAS detected
Last PFAS check: · Source: Hub'eau
PFAS in drinking water
No PFAS detected
The lab sees nothing below 3 ng/L, 6 times our benchmark of 0.5 ng/L. Water above our benchmark would pass this check unnoticed.
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.
More about this result
The US also limits PFOA and PFOS to 4 ng/L each, per substance.
The lab detects each of the four substances from 0.5 to 1.5 ng/L upward. None reached that limit, so their total is below 3 ng/L rather than zero.
checked on 8 July 2026
20 PFAS (see each substance)
| PFAS substance | Value |
|---|---|
| Acide perfluorodecane sulfonique (PFDS) | <0,001 µg/L |
| Acide perfluorobutanoïque (PFBA) | <0,0015 µg/L |
| Acide perfluoro tridecanoique (PFTrDA) | <0,001 µg/L |
| Acide sulfonique de perfluorobutane (PFBS) | <0,001 µg/L |
| Acide perfluorododécanoique (PFDoDA) | <0,0015 µg/L |
| Acide perfluorododécane sulfonique (PFDoDS) | <0,0015 µg/L |
| Acide perfluoro-decanoïque (PFDA) | <0,0015 µg/L |
| Acide perfluoroheptanoïque (PFHPA) | <0,001 µg/L |
| Acide perfluorohexanoïque (PFHXA) | <0,001 µg/L |
| Acide perfluoropentanoïque (PFPEA) | <0,0005 µg/L |
| Acide perfluorononane sulfonique (PFNS) | <0,001 µg/L |
| Acide perfluoro tridecane sulfonique (PFTrDS) | <0,0015 µg/L |
| Acide sulfonique de perfluorooctane (PFOS) | <0,0015 µg/L |
| Perfluorohexane sulfonate (PFHXS) | <0,0005 µg/L |
| Acide perfluoroheptane sulfonique (PFHpS) | <0,001 µg/L |
| Acide perfluoro undecane sulfonique (PFUnDS) | <0,0015 µg/L |
| Acide perfluoro undecanoïque (PFUnA) | <0,0015 µg/L |
| Acide perfluoropentane sulfonique (PFPS) | <0,001 µg/L |
| Acide perfluoro-octanoïque (PFOA) | <0,0005 µg/L |
| Acide perfluoro-nonanoïque (PFNA) | <0,0005 µg/L |
None found. The lab sees nothing below 3 ng/L, so our 0.5 ng/L benchmark cannot be checked.
Water report for Guern
Get new PFAS results for Guern, with a short explanation. At most one update a week, only when there's something new.
- EU legal limit
- none detected sum of 20 PFAS below the detection limit, limit 100 ng/L
- Last PFAS test
- 8 July 2026
- Water supplier
- S.T.G.S.
In Guern, none of the 4 most closely watched PFAS (PFAS-4) was detected at the latest PFAS check on 8 July 2026. The total is below 3 ng/L, the sum of the detection limits and 6 times our 0.5 ng/L benchmark. Sum of 20 PFAS: <SEUIL µg/L, below the EU legal limit (100 ng/L). 6 checks since 25 February 2025: PFAS-4 up to 1.5 ng/L, sometimes below the detection limit, averaging at least 0.3 ng/L over 12 months (non-detects as 0). Source: Hub'eau, Qualité de l'eau potable (Ministère de la Santé / OFB / BRGM).
Details and sources
PFAS over time in Guern
6 PFAS checks since 25 February 2025, values as published. Samples from 2 communes on the same network: it's the same water, so each one applies to Guern.
| Date | PFAS-4 | Sum of 20 PFAS | Sampled at |
|---|---|---|---|
| < detection limit | < detection limit | Guern | |
| < detection limit | 1.6 ng/L | Cléguérec | |
| 1.5 ng/L | 1.5 ng/L | Cléguérec | |
| < detection limit | < detection limit | Cléguérec | |
| < detection limit | < detection limit | Cléguérec | |
| < detection limit | < detection limit | Cléguérec |
“<” 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.
See all 21 test results
| What was tested | Value | Limit | Status |
|---|---|---|---|
| Nitrate | 16 mg/L | ≤ 50 mg/L | within the limit |
| Nitrite | <0,010 mg/L | ≤ 0.5 mg/L | within the limit |
| Lead | <0,5 µg/L | ≤ 10 µg/L | within the limit |
| Copper | 0.007 mg(Cu)/L | ≤ 2 mg(Cu)/L | within the limit |
| Nickel | 1.2 µg/L | ≤ 20 µg/L | within the limit |
| Arsenic | <0,5 µg/L | ≤ 10 µg/L | within the limit |
| Cadmium | <0,05 µg/L | ≤ 5 µg/L | within the limit |
| Chromium | <0,5 µg/L | ≤ 50 µg/L | within the limit |
| Uranium | 0.1 µg/L | ≤ 30 µg/L | within the limit |
| Fluoride | <0,10 mg/L | ≤ 1.5 mg/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 unité pH | 6.5–9 unité pH | within the limit |
| Water hardness | 12.9 °f | no limit | for reference |
| Electrical conductivity | 353 µS/cm | 200–1,100 µS/cm | within the limit |
| Chloride | 42.8 mg/L | ≤ 250 mg/L | within the limit |
| Sulphate | 12.6 mg/L | ≤ 250 mg/L | within the limit |
| Sodium | 14 mg/L | ≤ 200 mg/L | within the limit |
| Iron | 9 µg/L | ≤ 200 µg/L | within the limit |
| Turbidity | <0,30 NFU | ≤ 2 NFU | within the limit |
Frequently asked questions
Is tap water in Guern safe to drink?
Yes. At the check on 15 July 2026, the tap water in Guern was within every limit tested. “Eau d'alimentation conforme aux limites de qualité et satisfaisant aux références de qualité à l'exception de la présence de 10 spores, ou bactéries anaérobies sulfito-réductrices pour 100 ml ne satifaisant pas à la concentration de référence fixée à zéro pour 100 ml et présen tant une variation du dénombrement des germes totaux ou germes aérobie s revivifiables d’un facteur supérieur à 10 par rapport à la moyenne g éométrique des résultats sur le secteur pertinent.”
How high are PFAS levels in Guern's drinking water?
The total of 20 PFAS ("forever chemicals") was last measured at –. The EU limit is 100 ng/L, so this water is at – of the limit. (below the EU limit)
Does the water in Guern also meet the strictest limits in Europe?
As far as this check can tell, yes. None of the four compounds was quantified, so their total is below 3 ng/L, the sum of the laboratory's detection limits, and under Sweden's legal limit of 4 ng/L in force since 2026.
Are PFAS levels rising in Guern's tap water?
Too few quantified checks to say (1 since 25 February 2025). pfasnearme adds each new publication weekly; a trend needs at least three quantified values.
How hard is the water in Guern?
The water hardness in Guern is 12.9 °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 28 September 2026.
Nearby communes
The closest to Guern 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=56076
- License
- Licence Ouverte / Open Licence (Etalab)
- Retrieved
- 28 September 2026
- Supply networks
- GUERN
This site is a data project, not an official source. If in doubt, check with your water supplier or local authority.