Published on 29 April 2026

TFA – A persistent pollutant

Trifluoroacetic acid (TFA) is a highly mobile yet extremely stable substance. Itself a ‘forever chemical’, it is the smallest of the PFAS molecules produced when larger PFAS degrade. These might be refrigerants leaked from air conditioning systems and heat pumps, propellants used in aerosol cans and foams, or plant protection products used in agriculture.

TFA - emission sources — © FOEN

TFA dissolves easily in water and is not biodegradable, and so it is now found in rainwater, rivers, lakes and groundwater all over the world. Once released, it remains in the environment for a very long time.

How does TFA enter the environment?

When used, refrigerants and propellants are released into the air, where they are broken down by sunlight. This produces TFA, which is transported into the soil by rainfall and washed into lakes and rivers. TFA is also produced when some of the plant protection products used on agricultural crops break down.

Where is TFA found?

• In water: precipitation, lakes, rivers, groundwater and drinking water
• In the soil: particularly on agricultural land
• In plants: TFA is absorbed through the roots
• In animals and humans: TFA can accumulate in organisms.

Learn more about TFA from the FOEN

• Emission sources

  TFA enters the environment along a number of pathways: via gaseous refrigerants and propellants in foams and aerosol cans, plant protection products and veterinary medicines, and from industrial sources and wastewater treatment plants.

  TFA – Emission sources

• TFA in precipitation

  TFA is found in precipitation all over Switzerland. Concentrations are typically significantly higher in summer than during the rest of the year. A large proportion of TFA in precipitation originates from precursor compounds, which are broken down into TFA by UV radiation in the atmosphere.

  TFA in precipitation

• TFA in groundwater

  TFA is found in groundwater all over Switzerland. However, concentrations differ greatly depending on the location: they are significantly higher on arable land. TFA enters groundwater over large areas because of the application of plant protection products.

  TFA in groundwater

• TFA in rivers and lakes

  TFA is found in Swiss rivers and lakes. In rivers, concentrations tend to be higher downstream as substances accumulate. Peak concentrations in lakes are often lower than in rivers, as the large volume of water has a diluting effect and many lakes are located further upstream.

  TFA in rivers and lakes

Reducing TFA in the environment

The Federal Council has already decided to impose restrictions on TFA-forming refrigerants and propellants in revision of the Chemical Risk Reduction Ordinance (ORRChem). The potential of plant protection products to break down into TFA will be assessed when active substance authorisation is renewed in the EU. Further regulations are currently being discussed as part of efforts to introduce a comprehensive ban on PFASs in the European Union. The Federal Council will consider adopting into Swiss legislation any measures decided on by the EU.

Furthermore, the Federal Council intends to launch an action plan to reduce the impact of long-lasting chemicals on people and the environment – in particular PFAS, which include TFA. One objective of this measure is to strengthen cooperation between the Confederation and the cantons. On 19 December 2025 the Federal Council approved the report on this issue produced in response to the Moser Postulate 22.458

Press release 19.10.2025

Further information

• Links

  PFAS – was ist das?

  How trifluoroacetic acid (TFA) forms and spreads in the atmosphere Empa - Communication - TFA in water and atmosphere