PFAS in the tap water of Saint-Denis (La Réunion): 11 ng/L, 22x our 0.5 ng/L benchmark
Last PFAS check: · Source: Hub'eau
PFAS in drinking water
22× 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 96% of the cities we track
checked on 6 July 2026
20 PFAS (see each substance)
| PFAS substance | Value |
|---|---|
| Acide sulfonique de perfluorooctane (PFOS) | 0.007 µg/L |
| Perfluorohexane sulfonate (PFHXS) | 0.004 µg/L |
| Acide perfluorododécanoique (PFDoDA) | <0,002 µg/L |
| Acide perfluoropentane sulfonique (PFPS) | <0,002 µg/L |
| Acide perfluoroheptane sulfonique (PFHpS) | <0,002 µg/L |
| Acide perfluorododécane sulfonique (PFDoDS) | <0,002 µg/L |
| Acide perfluoro-nonanoïque (PFNA) | <0,002 µg/L |
| Acide perfluoro tridecanoique (PFTrDA) | <0,002 µg/L |
| Acide perfluoro-octanoïque (PFOA) | <0,002 µg/L |
| Acide perfluorodecane sulfonique (PFDS) | <0,002 µg/L |
| Acide perfluoro-decanoïque (PFDA) | <0,002 µg/L |
| Acide perfluorohexanoïque (PFHXA) | <0,005 µg/L |
| Acide perfluoro undecanoïque (PFUnA) | <0,002 µg/L |
| Acide perfluorobutanoïque (PFBA) | <0,005 µg/L |
| Acide perfluoroheptanoïque (PFHPA) | <0,002 µg/L |
| Acide sulfonique de perfluorobutane (PFBS) | <0,002 µg/L |
| Acide perfluoro undecane sulfonique (PFUnDS) | <0,002 µg/L |
| Acide perfluoropentanoïque (PFPEA) | <0,005 µg/L |
| Acide perfluorononane sulfonique (PFNS) | <0,002 µg/L |
| Acide perfluoro tridecane sulfonique (PFTrDS) | <0,005 µg/L |
Above our health benchmark. Here are some filter options.
- EU legal limit
- 11 ng/L sum of 20 PFAS, below the 100 ng/L limit
- Last PFAS test
- 6 July 2026
- Water supplier
- DIONEO
In Saint-Denis, the 4 most closely watched PFAS (PFAS-4) add up to 11 ng/L (0.011 µg/L) at the latest PFAS check on 6 July 2026. That's 22 times our 0.5 ng/L health benchmark, and above Sweden's legal limit of 4 ng/L. Sum of 20 PFAS: 11 ng/L (0.011 µg/L), below the EU legal limit (100 ng/L). 46 checks since 5 May 2025: PFAS-4 up to 25 ng/L, sometimes below the detection limit, averaging at least 12.22 ng/L over 12 months (non-detects as 0). No clear trend. Source: Hub'eau, Qualité de l'eau potable (Ministère de la Santé / OFB / BRGM).
Details and sources
PFAS over time in Saint-Denis
46 PFAS checks since 5 May 2025, values as published. Samples come from 13 distribution networks. The trend refers to the network “RESEAU STE-CLOTILDE B”.
| Date | PFAS-4 | Sum of 20 PFAS | Network |
|---|---|---|---|
| 11 ng/L | 11 ng/L | RESEAU STE-CLOTILDE B | |
| < 2 ng/L | < 5 ng/L | RESEAU ST-FRANCOIS B | |
| 25 ng/L | 46 ng/L | RESEAU STE-CLOTILDE A | |
| 9 ng/L | 9 ng/L | RESEAU STE-CLOTILDE B | |
| < 2 ng/L | < 5 ng/L | RESEAU DOMENJOD - COMMUNE PRIMA | |
| < 2 ng/L | < 5 ng/L | RESEAU ILET QUINQUINA | |
| < 2 ng/L | < 5 ng/L | RESEAU LA MONTAGNE | |
| 9 ng/L | 9 ng/L | RESEAU STE-CLOTILDE B | |
| < 2 ng/L | < 5 ng/L | RESEAU LA BRETAGNE | |
| 11 ng/L | 13 ng/L | RESEAU STE-CLOTILDE A | |
| < 2 ng/L | < 5 ng/L | RESEAU BELLEPIERRE | |
| 3 ng/L | 3 ng/L | RESEAU STE-CLOTILDE A |
Show the 34 earlier checks (back to 5 May 2025)
| < 2 ng/L | < 5 ng/L | RESEAU PARC TRINITE | |
| < 2 ng/L | < 5 ng/L | RESEAU LE BRULE | |
| 19 ng/L | 32 ng/L | RESEAU STE-CLOTILDE B | |
| 5 ng/L | 7 ng/L | RESEAU STE-CLOTILDE A | |
| < 4 ng/L | < 29 ng/L | RESEAU BELLEPIERRE | |
| < 4 ng/L | < 29 ng/L | RESEAU ST-FRANCOIS A | |
| 21 ng/L | 44 ng/L | RESEAU STE-CLOTILDE A | |
| < 40 ng/L | < 29 ng/L | RESEAU STE-CLOTILDE A | |
| 15 ng/L | 31 ng/L | RESEAU LE BRULE | |
| 23 ng/L | 52 ng/L | RESEAU STE-CLOTILDE A | |
| < 4 ng/L | < 29 ng/L | RESEAU LA BRETAGNE | |
| < 4 ng/L | < 29 ng/L | RESEAU ST-FRANCOIS A | |
| < 4 ng/L | < 29 ng/L | RESEAU BOIS DE NEFLES | |
| 16 ng/L | 28 ng/L | RESEAU STE-CLOTILDE B | |
| < 4 ng/L | < 29 ng/L | RESEAU ST-FRANCOIS A | |
| < 4 ng/L | < 29 ng/L | RESEAU DOMENJOD - COMMUNE PRIMA | |
| 15 ng/L | 26 ng/L | RESEAU STE-CLOTILDE B | |
| 12 ng/L | 26 ng/L | RESEAU STE-CLOTILDE A | |
| 17 ng/L | 30 ng/L | RESEAU STE-CLOTILDE B | |
| < 40 ng/L | < 29 ng/L | RESEAU BELLEPIERRE | |
| < 4 ng/L | < 29 ng/L | RESEAU BELLEPIERRE | |
| 20 ng/L | 45 ng/L | RESEAU STE-CLOTILDE A | |
| 14 ng/L | 41 ng/L | RESEAU STE-CLOTILDE B | |
| < 4 ng/L | < 29 ng/L | RESEAU LA GRANDE CHALOUPE | |
| < 1 ng/L | < 28 ng/L | RESEAU STE-CLOTILDE B | |
| < detection limit | < detection limit | RESEAU ST-FRANCOIS B | |
| 17 ng/L | 31 ng/L | RESEAU STE-CLOTILDE B | |
| < detection limit | < 100 ng/L | RESEAU BELLEPIERRE | |
| 9 ng/L | 13 ng/L | RESEAU STE-CLOTILDE B | |
| < detection limit | < 100 ng/L | RESEAU DOMENJOD - COMMUNE PRIMA | |
| 15 ng/L | 29 ng/L | RESEAU STE-CLOTILDE A | |
| < detection limit | < 100 ng/L | RESEAU ILET QUINQUINA | |
| < detection limit | 2 ng/L | RESEAU LA MONTAGNE | |
| < detection limit | < 100 ng/L | RESEAU PARC TRINITE |
“<” 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.
Outside a reference value: Electrical conductivity 81 µS/cm on 29 July 2026 (reference 200–1,100 µS/cm). These are indicator parameters with reference values, not legal limits.
| What was tested | Value | Limit | Status |
|---|---|---|---|
| Electrical conductivity | 81 µS/cm | 200–1,100 µS/cm | below the reference value |
See all 21 test results
| What was tested | Value | Limit | Status |
|---|---|---|---|
| Nitrate | 0.6 mg/L | ≤ 50 mg/L | within the limit |
| Nitrite | <0,05 mg/L | ≤ 0.5 mg/L | within the limit |
| Lead | 0.2 µg/L | ≤ 10 µg/L | within the limit |
| Copper | 0.0034 mg(Cu)/L | ≤ 2 mg(Cu)/L | within the limit |
| Nickel | <0,2 µg/L | ≤ 20 µg/L | within the limit |
| Arsenic | 0.09 µg/L | ≤ 10 µg/L | within the limit |
| Cadmium | <0,01 µg/L | ≤ 5 µg/L | within the limit |
| Chromium | 1.14 µg/L | ≤ 50 µg/L | within the limit |
| Uranium | 0.04 µg/L | ≤ 30 µg/L | within the limit |
| Fluoride | <0,10 mg/L | ≤ 1.5 mg/L | within the limit |
| Escherichia coli | <1 n/(100mL) | ≤ 0 mL) | within the limit |
| Enterococci | <1 n/(100mL) | ≤ 0 mL) | within the limit |
| Coliform bacteria | <1 n/(100mL) | ≤ 0 mL) | within the limit |
| pH | 8.1 unité pH | 6.5–9 unité pH | within the limit |
| Water hardness | 4 °f | no limit | for reference |
| Electrical conductivity | 81 µS/cm | 200–1,100 µS/cm | below the reference value |
| Chloride | <2,0 mg/L | ≤ 250 mg/L | within the limit |
| Sulphate | <0,5 mg/L | ≤ 250 mg/L | within the limit |
| Sodium | 12 mg/L | ≤ 200 mg/L | within the limit |
| Iron | <50 µg/L | ≤ 200 µg/L | within the limit |
| Turbidity | 0.27 NFU | ≤ 2 NFU | within the limit |
Frequently asked questions
Is tap water in Saint-Denis safe to drink?
Yes. At the check on 29 July 2026, the tap water in Saint-Denis was within every limit tested. Outside a reference value: Electrical conductivity 81 µS/cm on 29 July 2026 (reference 200–1,100 µS/cm). These are indicator parameters with reference values, not legal limits. “Eau d'alimentation conforme aux limites de qualité et non conforme aux références de qualité.”
How high are PFAS levels in Saint-Denis's drinking water?
The total of 20 PFAS ("forever chemicals") was last measured at 11 ng/L. The EU limit is 100 ng/L, so this water is at 11 % of the limit. (below the EU limit)
Does the water in Saint-Denis also meet the strictest limits in Europe?
No. The four most harmful PFAS add up to 11 ng/L. That is 2.8 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 Saint-Denis's tap water?
No clear trend. Since 5 May 2025, 46 checks have been published; on the main network the PFAS-4 sum ranged between 9 ng/L and 19 ng/L (10 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 Saint-Denis?
The water hardness in Saint-Denis is 4 °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 Saint-Denis 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=97411
- License
- Licence Ouverte / Open Licence (Etalab)
- Retrieved
- 28 September 2026
- Supply networks
- RESEAU BELLEPIERRE, RESEAU STE-CLOTILDE A, RESEAU STE-CLOTILDE B, RESEAU LE BRULE, RESEAU ST-FRANCOIS A, RESEAU ST-FRANCOIS B, RESEAU BOIS DE NEFLES, RESEAU ILET QUINQUINA, RESEAU LA MONTAGNE, RESEAU LA GRANDE CHALOUPE, RESEAU PARC TRINITE, RESEAU DOMENJOD - COMMUNE PRIMA, RESEAU LA BRETAGNE
Water report for Saint-Denis
Get new PFAS results for Saint-Denis, 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.