PFAS in Guignen's tap water: 4.87 ng/L, 9.7x our 0.5 ng/L benchmark
Last PFAS check: · Source: Hub'eau
PFAS in drinking water
9.7× 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.
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 92% of the cities we track
checked on 14 January 2026
20 PFAS (see each substance)
| PFAS substance | Value |
|---|---|
| Acide sulfonique de perfluorooctane (PFOS) | 0.0022 µg/L |
| Perfluorohexane sulfonate (PFHXS) | 0.0014 µg/L |
| Acide perfluoro-octanoïque (PFOA) | 0.0013 µg/L |
| Acide perfluorohexanoïque (PFHXA) | 0.001 µg/L |
| Acide sulfonique de perfluorobutane (PFBS) | 0.0007 µg/L |
| Acide perfluoro tridecane sulfonique (PFTrDS) | <0,00040 µg/L |
| Acide perfluorononane sulfonique (PFNS) | <0,00040 µg/L |
| Acide perfluoro-nonanoïque (PFNA) | <0,0010 µg/L |
| Acide perfluoro undecane sulfonique (PFUnDS) | <0,00040 µg/L |
| Acide perfluoro-decanoïque (PFDA) | <0,0010 µg/L |
| Acide perfluoro tridecanoique (PFTrDA) | <0,0010 µg/L |
| Acide perfluoropentanoïque (PFPEA) | <0,0050 µg/L |
| Acide perfluorododécanoique (PFDoDA) | <0,0010 µg/L |
| Acide perfluoropentane sulfonique (PFPS) | <0,00040 µg/L |
| Acide perfluoroheptanoïque (PFHPA) | <0,0010 µg/L |
| Acide perfluoro undecanoïque (PFUnA) | <0,0010 µg/L |
| Acide perfluorododécane sulfonique (PFDoDS) | <0,00040 µg/L |
| Acide perfluoroheptane sulfonique (PFHpS) | <0,00040 µg/L |
| Acide perfluorodecane sulfonique (PFDS) | <0,00040 µg/L |
| Acide perfluorobutanoïque (PFBA) | <0,0050 µg/L |
Above our health benchmark. Here are some filter options.
- EU legal limit
- 6.53 ng/L sum of 20 PFAS, below the 100 ng/L limit
- Last PFAS test
- 14 January 2026
- Water supplier
- SAUR 35
In Guignen, the 4 most closely watched PFAS (PFAS-4) add up to 4.87 ng/L (0.0049 µg/L) at the latest PFAS check on 14 January 2026. That's 9.7 times our 0.5 ng/L health benchmark, and above Sweden's legal limit of 4 ng/L. Sum of 20 PFAS: 6.53 ng/L (0.0065 µg/L), below the EU legal limit (100 ng/L). 5 checks since 14 April 2025: PFAS-4 from 0.6 ng/L to 8.97 ng/L, averaging 5.49 ng/L over 12 months. No clear trend. Source: Hub'eau, Qualité de l'eau potable (Ministère de la Santé / OFB / BRGM).
Details and sources
PFAS over time in Guignen
5 PFAS checks since 14 April 2025, values as published. Samples from 3 communes on the same network: it's the same water, so each one applies to Guignen.
| Date | PFAS-4 | Sum of 20 PFAS | Sampled at |
|---|---|---|---|
| 4.87 ng/L | 6.53 ng/L | Guignen | |
| 8.97 ng/L | 10.75 ng/L | Langon | |
| 6.8 ng/L | 19.24 ng/L | Langon | |
| 0.6 ng/L | 2.53 ng/L | Pipriac | |
| 6.23 ng/L | 7.04 ng/L | Langon |
“<” 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 | 14.8 mg/L | ≤ 50 mg/L | within the limit |
| Nitrite | <0,02 mg/L | ≤ 0.5 mg/L | within the limit |
| Lead | <1,0 µg/L | ≤ 10 µg/L | within the limit |
| Copper | 0.013 mg(Cu)/L | ≤ 2 mg(Cu)/L | within the limit |
| Nickel | 2.2 µg/L | ≤ 20 µg/L | within the limit |
| Arsenic | <0,20 µg/L | ≤ 10 µg/L | within the limit |
| Cadmium | <0,025 µg/L | ≤ 5 µg/L | within the limit |
| Chromium | <1,0 µg/L | ≤ 50 µg/L | within the limit |
| Uranium | <0,50 µg/L | ≤ 30 µg/L | within the limit |
| Fluoride | 0.078 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 | 15.3 °f | no limit | for reference |
| Electrical conductivity | 400 µS/cm | 200–1,100 µS/cm | within the limit |
| Chloride | 32.3 mg/L | ≤ 250 mg/L | within the limit |
| Sulphate | 22.9 mg/L | ≤ 250 mg/L | within the limit |
| Sodium | 22.1 mg/L | ≤ 200 mg/L | within the limit |
| Iron | <20 µg/L | ≤ 200 µg/L | within the limit |
| Turbidity | 0.46 NFU | ≤ 2 NFU | within the limit |
Frequently asked questions
Is tap water in Guignen safe to drink?
Yes. At the check on 20 July 2026, the tap water in Guignen 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 Guignen's drinking water?
The total of 20 PFAS ("forever chemicals") was last measured at 6.53 ng/L. The EU limit is 100 ng/L, so this water is at 7 % of the limit. (below the EU limit)
Does the water in Guignen also meet the strictest limits in Europe?
No. The four most harmful PFAS add up to 4.87 ng/L. That is 1.22 times Sweden's legal limit of 4 ng/L, in force since 2026. Germany will set a similar one in 2028. The water still passes the current EU legal limit (100 ng/L for the total of 20 PFAS).
Are PFAS levels rising in Guignen's tap water?
No clear trend. Since 14 April 2025, 5 checks have been published; on the main network the PFAS-4 sum ranged between 0.6 ng/L and 8.97 ng/L (5 quantified values), at times below the detection limit. pfasnearme only reports a trend from a change of at least 25 % and 1 ng/L.
How hard is the water in Guignen?
The water hardness in Guignen is 15.3 °f (medium). 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.
Same water network
Same distribution network as Guignen, so in principle the same water.
Nearby communes
The closest to Guignen 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=35127
- License
- Licence Ouverte / Open Licence (Etalab)
- Retrieved
- 21 September 2026
- Supply networks
- BRUYERES_FRAUX/PORT DE ROCHE_LOHEAC
Water report for Guignen
Get new PFAS results for Guignen, 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.