PFAS in Castries's tap water: under 4 ng/L, none of the four main PFAS detected

Last PFAS check: · Source: Hub'eau

PFAS in drinking water

No PFAS detected

Amount found in the water < 4 ng/L the 4 most harmful PFAS (PFAS-4) · the lab's detection limit 20 PFAS looked for, none found
Our health benchmark 0.5 ng/L

The lab sees nothing below 4 ng/L, 8 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.

Sample taken in Guzargues, on the same distribution network as Castries (SGC - EST). 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.

The lab detects each of the four substances from 1 ng/L upward. None reached that limit, so their total is below 4 ng/L rather than zero.

20 PFAS (see each substance)
PFAS substance Value
Acide perfluoro-nonanoïque (PFNA) <0,001 µg/L
Acide perfluoroheptanoïque (PFHPA) <0,001 µg/L
Acide perfluorododécane sulfonique (PFDoDS) <0,001 µg/L
Acide perfluorodecane sulfonique (PFDS) <0,001 µg/L
Acide perfluoro-octanoïque (PFOA) <0,001 µg/L
Acide sulfonique de perfluorobutane (PFBS) <0,001 µg/L
Acide perfluorononane sulfonique (PFNS) <0,002 µg/L
Acide perfluoro undecane sulfonique (PFUnDS) <0,002 µg/L
Acide perfluorododécanoique (PFDoDA) <0,001 µg/L
Acide perfluoropentanoïque (PFPEA) <0,001 µg/L
Acide perfluoropentane sulfonique (PFPS) <0,001 µg/L
Acide perfluorobutanoïque (PFBA) <0,002 µg/L
Perfluorohexane sulfonate (PFHXS) <0,001 µg/L
Acide perfluoro-decanoïque (PFDA) <0,001 µg/L
Acide sulfonique de perfluorooctane (PFOS) <0,001 µg/L
Acide perfluorohexanoïque (PFHXA) <0,002 µg/L
Acide perfluoro tridecane sulfonique (PFTrDS) <0,005 µg/L
Acide perfluoroheptane sulfonique (PFHpS) <0,002 µg/L
Acide perfluoro undecanoïque (PFUnA) <0,001 µg/L
Acide perfluoro tridecanoique (PFTrDA) <0,001 µg/L

None found. The lab sees nothing below 4 ng/L, so our 0.5 ng/L benchmark cannot be checked.

EU legal limit
none detected sum of 20 PFAS below the detection limit, limit 100 ng/L
Last PFAS test
7 July 2026
Water supplier
S.A. RUAS MICHEL GROUPE VEOLIA

In Castries, none of the 4 most closely watched PFAS (PFAS-4) was detected at the latest PFAS check on 7 July 2026. The total is below 4 ng/L, the sum of the detection limits and 8 times our 0.5 ng/L benchmark. Sum of 20 PFAS: <0,029 µg/L, below the EU legal limit (100 ng/L). Sampled in Guzargues, on the same network. 8 checks since 10 July 2025: sum of 20 PFAS up to 22 ng/L, sometimes below the detection limit. Source: Hub'eau, Qualité de l'eau potable (Ministère de la Santé / OFB / BRGM).

Details and sources
Water supplier: S.A. RUAS MICHEL GROUPE VEOLIA Latest water check: 24 July 2026 Data updated on

PFAS over time in Castries

8 PFAS checks since 10 July 2025, from the published measurements. Samples from 5 communes on the same network: it's the same water, so each one applies to Castries. Samples come from 3 distribution networks. The trend refers to the network “SGC - EST”.

“Calculated”: PFAS-4 worked out from the four substances in the same sample. The chart, averages and trends use lab-published sums only.

22 ng/L010 July 20257 July 2026
Laboratory-published sum of 20 PFAS per check in ng/L. Hollow dots: below the detection limit. Calculated PFAS-4 values are listed in the table.
DatePFAS-4Sum of 20 PFASSampled atNetwork
< 4 ng/L< 29 ng/LGuzarguesSGC - EST
< 4 ng/L · calculated< 29 ng/LRestinclièresSGC - EST
11 ng/L – < 12 ng/L · calculated22 ng/LCastriesSGC - EST
2 ng/L – < 4 ng/L · calculated6 ng/LCastries034004283, 034004283 +1
< 4 ng/L · calculated4 ng/LRestinclièresSGC - EST
< 4 ng/L · calculated< 29 ng/LGalarguesSGC - EST
4 ng/L – < 6 ng/L · calculated11 ng/LCastries034004283, 034004283 +1
< 4 ng/L · calculated1 ng/LSaint-Hilaire-de-BeauvoirSGC - EST

Calculated values: “<” is an upper bound from published thresholds, “≥” a lower bound, “–” means no published sum or complete measurement. How to read a PFAS result

What the latest check found

At the latest check, the water was within every limit tested.

Microbiology: within the limit Chemistry: within the limit
See all 20 test results
What was tested Value Limit Status
Nitrate 9.2 mg/L ≤ 50 mg/L within the limit
Nitrite <0,01 mg/L ≤ 0.5 mg/L within the limit
Lead – ≤ 10 µg/L no verdict
Copper 0.05 mg(Cu)/L ≤ 2 mg(Cu)/L within the limit
Nickel <5 µg/L ≤ 20 µg/L within the limit
Arsenic – ≤ 10 µg/L no verdict
Cadmium – ≤ 5 µg/L no verdict
Chromium <5 µg/L ≤ 50 µg/L within the limit
Fluoride 0.1 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 7.66 unité pH 6.5–9 unité pH within the limit
Water hardness 29.12 °f no limit for reference
Electrical conductivity 598 µS/cm 200–1,100 µS/cm within the limit
Chloride 28 mg/L ≤ 250 mg/L within the limit
Sulphate 40.3 mg/L ≤ 250 mg/L within the limit
Sodium 13.9 mg/L ≤ 200 mg/L within the limit
Iron <10 µg/L ≤ 200 µg/L within the limit
Turbidity <0,1 NFU ≤ 2 NFU within the limit

Frequently asked questions

Is tap water in Castries safe to drink?

Yes. At the check on 24 July 2026, the tap water in Castries 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 Castries's drinking water?

At the latest check the total of 20 PFAS ("forever chemicals") was below the laboratory's reporting limit of 29 ng/L. The EU limit is 100 ng/L, so this water is under 29 % of the limit. (below the EU limit)

Does the water in Castries 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 4 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 Castries's tap water?

Calculated PFAS-4 values are listed in the table. The chart uses laboratory-published sum-of-20 results; there are too few laboratory-published PFAS-4 sums for the existing trend calculation.

How hard is the water in Castries?

The water hardness in Castries is 29.1 °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 Castries, so in principle the same water.

Nearby communes

The closest to Castries 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=34058
License
Licence Ouverte / Open Licence (Etalab)
Retrieved
21 September 2026
Supply networks
S. GC-CASTRIES, SGC - EST

This site is a data project, not an official source. If in doubt, check with your water supplier or local authority.