Developments regarding drinking water contamination by PFAS in Switzerland

1. Per- and polyfluorinated alkyl compounds (PFAS)

Per- and polyfluorinated alkyl compounds are a group of persistent chemicals (‘forever chemicals’¹) that are produced industrially. These PFAS are released into the environment and can be detected in the food chain and in humans. These substances pose a health risk to humans. Substances that belong to PFAS include perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS).²  PFOS is a particularly harmful substance from the PFAS group.³

Due to the listed properties of PFAS and their substances, specific regulations on maximum levels of PFAS, including in drinking water, have been adopted in both the EU and Switzerland.

2. Background and directives in the EU

In Directive (EU) 2020/2184 of the European Parliament and of the Council of 16 December 2020 on the quality of water intended for human consumption, the EU regulates the conditions for protecting human health from the adverse effects of the contamination of water intended for human consumption. To achieve this goal, the directive defines, among other things, maximum levels for substances belonging to PFAS.

For example, Part B of Annex III of the directive states that the “Sum of PFAS” that are considered to be of concern with regard to water intended for human consumption must not exceed the parameter value of 0.1μg/l. The “sum of PFAS” includes perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA).

Article 25 of the Directive requires Member States to take the necessary measures by 12 January 2026 to ensure that water intended for human consumption complies with the rules set out above. Member States shall then ensure that producers of water intended for human consumption which is put into bottles or other containers comply with Articles 1 to 5.

3. Regulation in Switzerland

In Switzerland, the Federal Department of Home Affairs (FDHA) regulates the treatment, provision and quality of drinking water as a foodstuff and water as a commodity in the FDHA Ordinance on Drinking Water and Water in Publicly Accessible Baths and Showers (TBDV) of 16 December 2016.

Article 3 TBDV stipulates that drinking water must be inconspicuous in terms of odour, taste and appearance and must not pose a health risk in terms of the type and concentration of microorganisms, parasites and contaminants it contains. Furthermore, the minimum requirements that water must fulfil are regulated in Annexes 1-3. For example, the maximum levels of PFAS in drinking water are regulated in accordance with Annex 2 TBDV. The maximum value for PFOS is currently 0.3 µg/l. The maximum value for PFOA is 0.5 µg/litre.

In principle, Switzerland is not bound by the EU directives. However, if products comply with the technical regulations of the European Community and are regularly marketed there, they may also be marketed in Switzerland.⁴ The Foodstuffs Act also aims to harmonise with EU law in order to simplify economic progress.⁵

The Federal Food Safety and Veterinary Office (FSVO) is now reviewing the TBDV maximum values due to the new requirements regarding PFAS in the EU Drinking Water Directive. These are expected to be set at the maximum value of 0.1 µg/l for the sum of 20 selected PFAS, based on the EU Drinking Water Directive. In Switzerland, the new maximum value will apply from 2026 in line with the implementation in the EU.⁶

4. Parties affected by the TBDV

With regard to the above regulations concerning maximum levels of PFAS, the question arises as to who is specifically affected by these regulations. Drinking water must first be categorised as a foodstuff in accordance with Art. 4 para. 2 lit. a LMG. The handling of foodstuffs is regulated in the Foodstuffs Act from production to treatment, storage, transport and placing on the market.⁷ In principle, everyone who ‘handles’ food is subject to the general obligation to ensure the necessary hygiene. Companies that place food on the market are then subject to self-regulation. The distribution of foodstuffs is understood to mean any form of transfer against payment or free of charge, the holding ready for distribution against payment or free of charge, the offering for distribution and the distribution itself.⁸

¹ Flohr/Horlacher, SRF-News, Karte der ewigen Belastungen: Hier sind PFAS zu finden.

² BLV, Per- und polyfluorierte Alkylverbindungen (PFAS).

³ Flohr/Horlacher, SRF-News, Karte der ewigen Belastungen: Hier sind PFAS zu finden.

⁴ Article 16a THG.

⁵ Message on FSA, p. 5584.

⁶ FSVO, Per- and polyfluorinated alkyl compounds (PFAS).

⁷ Article 2 FSA.

⁸ Article 6 FSA.