PFAS in tap water in Belgium
Official PFAS results for 546 cities in Belgium, from VMM and SPW-ARNE / SWDE. The newest is from 17 December 2025. 270 of 546 cities with a PFAS-4 value are at or above our 0.5 ng/L benchmark. 63 are above 4 ng/L, Sweden's legal limit. The highest PFAS-4 values: Saint-Hubert (24 ng/L), Nandrin (19 ng/L) and Leuven (18 ng/L). Data updated on 28 September 2026.
By region
| Area | Cities | With PFAS-4 value | At/above 0.5 ng/L | Highest PFAS-4 |
|---|---|---|---|---|
| Flanders | 285 | 285 | 222 | Leuven, 18 ng/L |
| Wallonia | 261 | 261 | 48 | Saint-Hubert, 24 ng/L |
Provinces
| Area | Cities | With PFAS-4 value | At/above 0.5 ng/L | Highest PFAS-4 |
|---|---|---|---|---|
| Antwerp | 67 | 67 | 55 | Kontich, 4.9 ng/L |
| Flemish Brabant | 63 | 63 | 46 | Leuven, 18 ng/L |
| Walloon Brabant | 27 | 27 | 12 | Waterloo, 3 ng/L |
| West Flanders | 62 | 62 | 46 | Kortrijk, 6 ng/L |
| East Flanders | 55 | 55 | 52 | Lokeren, 7 ng/L |
| Hainaut | 69 | 69 | 18 | Chimay, 7 ng/L |
| Liège | 84 | 84 | 6 | Nandrin, 19 ng/L |
| Limburg | 38 | 38 | 23 | Bilzen-Hoeselt, 10 ng/L |
| Luxembourg | 43 | 43 | 3 | Saint-Hubert, 24 ng/L |
| Namur | 38 | 38 | 9 | Florennes, 5.7 ng/L |
The 20 cities with the highest PFAS-4 values in Belgium
Ranked by the measured PFAS-4 sum. Each row links to the city's page.
| # | City | PFAS-4 | Date | Population |
|---|---|---|---|---|
| 1 | Saint-Hubert · Wallonia | 24 ng/L | 5,741 | |
| 2 | Nandrin · Wallonia | 19 ng/L | 5,735 | |
| 3 | Leuven · Flanders | 18 ng/L | 105,357 | |
| 4 | Lubbeek · Flanders | 18 ng/L | 15,290 | |
| 5 | Oud-Heverlee · Flanders | 18 ng/L | 11,414 | |
| 6 | Bierbeek · Flanders | 18 ng/L | 10,926 | |
| 7 | Boutersem · Flanders | 18 ng/L | 8,678 | |
| 8 | La Calamine · Wallonia | 12 ng/L | 11,332 | |
| 9 | Bilzen-Hoeselt · Flanders | 10 ng/L | 43,228 | |
| 10 | Maasmechelen · Flanders | 10 ng/L | 40,653 | |
| 11 | Lanaken · Flanders | 10 ng/L | 26,513 | |
| 12 | Dilsen-Stokkem · Flanders | 10 ng/L | 21,677 | |
| 13 | Zutendaal · Flanders | 10 ng/L | 7,477 | |
| 14 | Hasselt · Flanders | 9 ng/L | 90,914 | |
| 15 | Diepenbeek · Flanders | 9 ng/L | 19,867 | |
| 16 | Alken · Flanders | 9 ng/L | 11,943 | |
| 17 | Genk · Flanders | 8 ng/L | 68,101 | |
| 18 | As · Flanders | 8 ng/L | 8,249 | |
| 19 | Lokeren · Flanders | 7 ng/L | 50,897 | |
| 20 | Zele · Flanders | 7 ng/L | 21,587 |
The 20 lowest quantified PFAS-4 values in Belgium
Only values above the detection limit are ranked. In 276 cities none of the four substances was detected.
| # | City | PFAS-4 | Date | Population |
|---|---|---|---|---|
| 1 | Ieper · Flanders | 0.5 ng/L | 35,629 | |
| 2 | Aarschot · Flanders | 0.5 ng/L | 31,948 | |
| 3 | Scherpenheuvel-Zichem · Flanders | 0.5 ng/L | 24,537 | |
| 4 | Tielt-Winge · Flanders | 0.5 ng/L | 11,585 | |
| 5 | Bertem · Flanders | 0.5 ng/L | 10,394 | |
| 6 | Huldenberg · Flanders | 0.5 ng/L | 10,132 | |
| 7 | Tubize · Wallonia | 1 ng/L | 29,043 | |
| 8 | Ronse · Flanders | 1 ng/L | 27,731 | |
| 9 | Braine-le-Comte · Wallonia | 1 ng/L | 23,761 | |
| 10 | Middelkerke · Flanders | 1 ng/L | 20,069 | |
| 11 | Ichtegem · Flanders | 1 ng/L | 14,681 | |
| 12 | Gistel · Flanders | 1 ng/L | 12,098 | |
| 13 | Oudenburg · Flanders | 1 ng/L | 10,449 | |
| 14 | Bassenge · Wallonia | 1 ng/L | 9,059 | |
| 15 | Koekelare · Flanders | 1 ng/L | 8,886 | |
| 16 | Ittre · Wallonia | 1 ng/L | 6,918 | |
| 17 | Turnhout · Flanders | 1.1 ng/L | 48,490 | |
| 18 | Châtelet · Wallonia | 1.1 ng/L | 35,975 | |
| 19 | Courcelles · Wallonia | 1.1 ng/L | 31,673 | |
| 20 | Morlanwelz · Wallonia | 1.1 ng/L | 19,143 |
How to read this page
PFAS-4 is the sum of PFOA, PFOS, PFNA and PFHxS, the four PFAS that EFSA judges most harmful. Values are in nanograms per litre (ng/L); 1 ng/L = 0.001 µg/L.
Three reference values: 0.5 ng/L, our health benchmark (a proposal, not a legal limit); 4 ng/L, Sweden's legal limit since 2026 and the strictest PFAS-4 limit in Europe; 100 ng/L for the sum of 20 PFAS, the EU legal limit since January 2026.
Labs count undetected substances as zero, so a PFAS-4 sum is a minimum. A city only counts as "at or above 0.5 ng/L" when the measurement proves it, and a non-detect only counts as below when the detection limits allow it.
Flemish values are the annual median per supply area from the VMM report (the year's maximum is shown alongside), Walloon values are dated samples from the SPW PFAS monitoring. A Flemish maximum above 4 ng/L is "above the 2028 target", not a legal failure.
Legal limits and dates in Belgium
Belgium applies the EU limit of 100 ng/L for the sum of 20 PFAS as binding law (Flemish Drinkwaterbesluit of 2023, Walloon Code de l'eau since February 2025). For the four most harmful PFAS (PFAS-4) all three regions set a target of 4 ng/L that becomes binding in 2028. This site's 0.5 ng/L benchmark is stricter than both.
Sources, regulators and licences
Drinking water is a regional competence in Belgium: the Vlaamse Milieumaatschappij (VMM) publishes the Flemish results per supply area, the Service public de Wallonie (SPW-ARNE) with SWDE the Walloon PFAS monitoring. Brussels (Vivaqua) is not covered yet.
- Vlaamse Milieumaatschappij (VMM), Kwaliteit van het drinkwater 2024, bijlage 2 · 323 cities · Licence: Modellicentie voor gratis hergebruik (Vlaamse overheid) – https://vmm.vlaanderen.be/disclaimer
Flanders: Vlaamse Milieumaatschappij (VMM), drinking water quality 2024, one annual figure per supply area (median and maximum of the measurements in the network). Licence: free reuse with attribution (Flemish model licence). Next edition expected in October 2026.
- Service public de Wallonie (SPW-ARNE) / SWDE, Etat des lieux du monitoring PFAS dans les eaux distribuées · 262 cities · Licence: reuse licence being confirmed with the source
Wallonia: Service public de Wallonie (SPW-ARNE) with SWDE, PFAS monitoring of distributed water, one row per sample and distribution zone, September 2023 to December 2025. The reuse licence for this document is still to be confirmed with SPW; attributed to SPW-ARNE and SWDE meanwhile.
Frequently asked questions
How much PFAS is in tap water in Belgium?
This page summarises the official PFAS results in the tap water of 546 cities in Belgium, published by VMM and SPW-ARNE / SWDE. The measured value is PFAS-4, the sum of PFOA, PFOS, PFNA and PFHxS, in nanograms per litre (ng/L). The most recent result dates from 17 December 2025. 546 of the 546 cities have a PFAS-4 value. 270 of them (49.5 %) are at or above 0.5 ng/L, this site's health benchmark, and 63 (11.5 %) are above 4 ng/L, the strictest legal PFAS-4 limit in force in Europe (Sweden, since 2026).
Which city in Belgium has the highest PFAS-4 value?
Saint-Hubert: 24 ng/L (48× the 0.5 ng/L benchmark), result of 31 March 2025. Source: SPW-ARNE / SWDE – Etat des lieux du monitoring PFAS dans les eaux distribuées (sept. 2023 – déc. 2025). The 20 highest values are in the table above.
Which PFAS limits apply in Belgium?
Belgium applies the EU limit of 100 ng/L for the sum of 20 PFAS as binding law (Flemish Drinkwaterbesluit of 2023, Walloon Code de l'eau since February 2025). For the four most harmful PFAS (PFAS-4) all three regions set a target of 4 ng/L that becomes binding in 2028. This site's 0.5 ng/L benchmark is stricter than both.
Is tap water in Belgium safe to drink?
Drinking water is a regional competence in Belgium: the Vlaamse Milieumaatschappij (VMM) publishes the Flemish results per supply area, the Service public de Wallonie (SPW-ARNE) with SWDE the Walloon PFAS monitoring. Brussels (Vivaqua) is not covered yet. Against the EU limit of 100 ng/L for the sum of 20 PFAS, no covered city is non-compliant. Against Sweden's stricter 4 ng/L PFAS-4 limit, 63 cities would be above, and 270 against this site's 0.5 ng/L benchmark. What a result means for you is explained on your city's page.
Where does this data come from?
All values come from official publications: Vlaamse Milieumaatschappij (VMM), Kwaliteit van het drinkwater 2024, bijlage 2; Service public de Wallonie (SPW-ARNE) / SWDE, Etat des lieux du monitoring PFAS dans les eaux distribuées. Last retrieved on 28 September 2026; the site refreshes the data weekly, and the latest result date on each city page is authoritative.
How do I cite these figures?
Name the city, the sample date shown on the page, the source and the page URL. The "Source and citation" block below and on every city page contains a ready-made citation sentence; each source's licence is listed next to it.
Data and downloads
- One JSON file per city (values, samples, networks, source, licence):
/report/be/{slug}.json(example: /report/be/saint-hubert-84059.json). - Every city page of Belgium is listed in the sitemap: /sitemap-communes-be-0.xml (/sitemap-index.xml).
- Plain-text summary of the site for AI assistants and crawlers: /llms.txt (full version with the methodology: /llms-full.txt).
- This page and every city page carry schema.org Dataset markup with the licence, the values, the sample date and the source.
The water report for your city
Choose your city to understand the available results and receive new PFAS results.
Choose my cityThis site is a data project, not an official source. If in doubt, check with your water supplier or local authority.