PFAS in Merfy's tap water: 1 ng/L, 2x our 0.5 ng/L benchmark

Last PFAS check: · Source: Hub'eau

PFAS in drinking water

2× above our health benchmark

Amount found in the water 1 ng/L 0.001 µg/L · the 4 most harmful PFAS (PFAS-4)
Our health benchmark 0.5 ng/L

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 Chenay, on the same distribution network as Merfy (CUGR CHENAY-MERFY-TRIGNY). 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 82% of the cities we track

20 PFAS (see each substance)
PFAS substance Value
Acide sulfonique de perfluorooctane (PFOS) 0.001 µg/L
Acide perfluoroheptanoïque (PFHPA) <0,001 µg/L
Acide perfluoro tridecane sulfonique (PFTrDS) <0,005 µg/L
Acide perfluorodecane sulfonique (PFDS) <0,001 µg/L
Acide perfluoropentane sulfonique (PFPS) <0,001 µg/L
Acide perfluorononane sulfonique (PFNS) <0,002 µg/L
Acide perfluoropentanoïque (PFPEA) <0,001 µg/L
Acide perfluoro tridecanoique (PFTrDA) <0,001 µg/L
Acide perfluorobutanoïque (PFBA) <0,002 µg/L
Acide perfluoro undecane sulfonique (PFUnDS) <0,002 µg/L
Acide perfluoro undecanoïque (PFUnA) <0,001 µg/L
Acide perfluoro-nonanoïque (PFNA) <0,001 µg/L
Perfluorohexane sulfonate (PFHXS) <0,001 µg/L
Acide perfluorohexanoïque (PFHXA) <0,002 µg/L
Acide perfluoro-octanoïque (PFOA) <0,001 µg/L
Acide perfluoroheptane sulfonique (PFHpS) <0,002 µg/L
Acide perfluorododécane sulfonique (PFDoDS) <0,001 µg/L
Acide perfluoro-decanoïque (PFDA) <0,001 µg/L
Acide perfluorododécanoique (PFDoDA) <0,001 µg/L
Acide sulfonique de perfluorobutane (PFBS) <0,001 µg/L

Above our health benchmark. Here are some filter options.

EU legal limit
1 ng/L sum of 20 PFAS, below the 100 ng/L limit
Last PFAS test
18 March 2026
Water supplier
EAU ARDRE ET VESLE (CLIG51)

In Merfy, the 4 most closely watched PFAS (PFAS-4) add up to 1 ng/L (0.001 µg/L) at the latest PFAS check on 18 March 2026. That's 2 times our 0.5 ng/L health benchmark, but below Sweden's legal limit of 4 ng/L. Sum of 20 PFAS: 1 ng/L (0.001 µg/L), below the EU legal limit (100 ng/L). Sampled in Chenay, on the same network. 2 checks since 6 May 2025: sum of 20 PFAS from 1 ng/L to 3 ng/L. Source: Hub'eau, Qualité de l'eau potable (Ministère de la Santé / OFB / BRGM).

Details and sources
Water supplier: EAU ARDRE ET VESLE (CLIG51) Latest water check: 31 July 2026 Data updated on

PFAS over time in Merfy

2 PFAS checks since 6 May 2025, from the published measurements.

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

3 ng/L06 May 202518 March 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 at
1 ng/L – < 4 ng/L · calculated1 ng/LChenay
2 ng/L – < 5 ng/L · calculated3 ng/LChenay

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

The authorities have not published an overall verdict for this water.

Microbiology: no verdict Chemistry: within the limit

Values to watch

These results are close to their legal limit, or over it.

What was tested Value Limit Status
Nitrate 25.5 mg/L ≤ 50 mg/L within the limit
See all 16 test results
What was tested Value Limit Status
Nitrate 25.5 mg/L ≤ 50 mg/L within the limit
Nitrite <0,010 mg/L ≤ 0.5 mg/L within the limit
Lead 3.4 µg/L ≤ 10 µg/L within the limit
Copper 0.06 mg(Cu)/L ≤ 2 mg(Cu)/L within the limit
Nickel 3.9 µg/L ≤ 20 µg/L within the limit
Cadmium <0,5 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 7.4 unité pH 6.5–9 unité pH within the limit
Electrical conductivity 515 µS/cm 200–1,100 µS/cm within the limit
Chloride 15.9 mg/L ≤ 250 mg/L within the limit
Sulphate 13 mg/L ≤ 250 mg/L within the limit
Iron <5 µg/L ≤ 200 µg/L within the limit
Turbidity <0,30 NFU ≤ 2 NFU within the limit

Frequently asked questions

Is tap water in Merfy safe to drink?

All the values shown here (31 July 2026) are within the legal limits, but the authorities have not published an overall verdict for this water. “Eau d'alimentation conforme aux exigences de qualité en vigueur pour l'ensemble des paramètres mesurés.”

How high are PFAS levels in Merfy's drinking water?

The total of 20 PFAS ("forever chemicals") was last measured at 1 ng/L. The EU limit is 100 ng/L, so this water is at 1 % of the limit. (below the EU limit)

Does the water in Merfy 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 1 ng/L stays below.

Are PFAS levels rising in Merfy'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 Merfy?

No hardness value is available for Merfy in this source.

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 Merfy, so in principle the same water.

Nearby communes

The closest to Merfy 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=51362
License
Licence Ouverte / Open Licence (Etalab)
Retrieved
21 September 2026
Supply networks
CUGR CHENAY-MERFY-TRIGNY

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