Trifluoroacetic acid
Profile
Trifluoroacetic acid, or trifluoroacetate (TFA), is a short-chain perfluorocarboxylic acid and the final degradation product of many fluorinated compounds. When fluorinated gases, which are widely used as refrigerants in heat pumps, air conditioning systems and refrigerators, for example, are released into the atmosphere, they are chemically altered by UV radiation and converted into TFA. However, fluorinated compounds are also used in plant protection products and medicines, and TFA can also be produced from these. TFA is very persistent; its high water solubility means that it is highly mobile in the soil and can easily enter the groundwater.
Occurrence
Due to the widespread use of fluorinated compounds and its persistence, TFA is now found throughout the environment. It can be detected in groundwater, rainwater, rivers, seas, soil and even in plants, with concentrations being highest in summer due to photochemical activity in the atmosphere (Bavarian State Office for the Environment).
The German Federal Environment Agency reports average TFA levels in precipitation of 0.335 μg/L (Federal Environment Agency 2023).
Health effects
TFA is ingested via food or drinking water, is partially incorporated into the enterohepatic circulation (the circulation of certain substances in the mammalian body between the intestine, liver and gallbladder), distributed throughout the body (including the placenta) and rapidly excreted via urine and faeces.
The acute toxicity of TFA is very low. The EFSA has derived an Acceptable Daily Intake (ADI) for TFA of 0.05 mg/kg body weight (BW) per day, based on a 90-day rat study and an uncertainty factor (UF) of 200 for the extrapolation from subchronic to chronic exposure. Based on the available toxicological studies, it was not necessary to derive an acute reference dose (ARfD) (EFSA 2014, 2017).
Based on recent studies on developmental toxicity in rabbits, the EFSA is currently conducting a risk assessment (for further information, see the technical information section).
The situation in Austria
In Austria, TFA has been analysed in groundwater as part of the Water Status Monitoring Programme (GZÜV). TFA is commonly detected in groundwater in Austria. Since 2018, a total of 281 groundwater samples have been analysed for TFA. Of these, concentrations above the limit of quantification were found in 274 samples. The measured values averaged 1.4 µg/l, with the highest measured value being 21 µg/l (H2O specialist database – public quality data query).
In 2025, AGES analysed TFA in drinking water as part of an Austria-wide monitoring programme. Of the 331 drinking water samples, TFA was detected in 307 samples (corresponding to 93%) at concentrations above the limit of quantification of 0.1 µg/l. The highest measured concentration was 6.03 µg/l. There is currently no EU-wide harmonised limit value (parameter value) for TFA in drinking water.
The German Federal Environment Agency (2020) has derived a health guideline value of 60 µg/l and points out that a concentration of 10 µg/l or less of TFA in drinking water should be aimed for. The Dutch National Institute for Public Health and the Environment (RIVM 2023) has derived an indicative drinking water value of 2.2 µg/l. In Denmark, a limit value of 9 µg/l has been set for TFA in drinking water (Drikkevandsbekendtgørelsen).
The guideline “Handling of unregulated contaminants in drinking water, BMG-75210/0023-II/B/13/2014” stipulates that maximum levels set by other countries may be used to determine derived tolerance values. As soon as a new risk assessment from the EFSA is available, a new tolerance value should be derived.
In 2025, the European Commission issued a recommendation on the monitoring of TFA in foodstuffs, on the basis of which corresponding monitoring of plant-based foods is currently being carried out in Austria. A final assessment is not yet available.
Technical information
Risk assessment
The European Commission has tasked the EFSA with preparing an opinion on the revision of the toxicological reference values for TFA (“reviewing the toxicological reference values for trifluoroacetic acid (TFA)”).
The draft TFA opinion was open for public consultation from 22 July 2025 to 22 September 2025 (https://open.efsa.europa.eu/consultations/a0cTk00000Gj0ilIAB?search=trifluoroacetic). The comments are now being discussed by the EFSA working group and will be incorporated into the assessment where appropriate. A final EFSA opinion is due to be published by the end of July 2026.
Furthermore, EFSA and ECHA are working on a joint assessment of the fate and behaviour of TFA in soil and water: “Joint Request to EFSA and ECHA to consider the fate and behaviour of trifluoroacetic acid (TFA) in soil and water.” – Planned duration: 18 months, Dec. 2025 – June 2027, Open EFSA.
Due to new toxicological data on developmental toxicity, the human toxicological relevance of TFA is currently being reassessed in several active substance renewal procedures for plant protection products. A plant protection product active substance metabolite is considered to be of human toxicological relevance within the meaning of the Plant Protection Products Regulation (Regulation (EC) No 1107/2009) if there is reason to believe that it possesses certain toxicological properties that are deemed unacceptable.
Due to the ongoing procedure for the human toxicological reclassification of TFA at the European Chemicals Agency (ECHA), AGES has refrained from conducting a preliminary human toxicological assessment in its report “Metabolites in Groundwater and Drinking Water. Re-evaluation of the Biological and Human Toxicological Relevance of Plant Protection Product Active Substance Metabolites”. The report recommends that, until an EU-wide harmonised classification in accordance with the CLP Regulation (Regulation (EC) No 1272/2008) is available, TFA should be considered, as a precautionary measure, to be of human toxicological relevance within the meaning of the Plant Protection Products Regulation. This must be taken into account to a particular extent in a risk assessment of TFA in drinking water within the meaning of the Drinking Water Ordinance.
Hazard and labelling classification by the European Chemicals Agency (ECHA)
The hazard classification and labelling of TFA is carried out by the European Chemicals Agency (ECHA). The assessment by ECHA’s Committee for Risk Assessment (RAC) is based exclusively on the hazardous properties of the substance and the question of whether the substance can cause adverse effects. The risk or the extent to which people and the environment are exposed to the substance is not taken into account.
The German Federal Office for Chemicals (BfC), together with the Federal Environment Agency (UBA) and the Federal Institute for Risk Assessment (BfR), has submitted a report in accordance with the CLP Regulation on the harmonised classification and labelling of trifluoroacetic acid (TFA) and its salts to the European Chemicals Agency (ECHA). According to the assessment by the German authorities, TFA is toxic to reproduction and is very persistent and very mobile in the environment. The report is available for public consultation on the ECHA website until 25 July 2025. The ECHA’s Scientific Committee on Risk Assessment (RAC) will then discuss the report from the German authorities and the comments received. The resulting opinion from the RAC will be submitted to the European Commission to draft a corresponding regulation amending the CLP Regulation.
ECHA’s current classification of TFA and Germany’s proposed classification can be found here.
OECD definition of PFAS
According to the Organisation for Economic Co-operation and Development (OECD), PFAS are defined as fluorinated substances containing at least one fully fluorinated methyl or methylene carbon atom (without an H/Cl/Br/I atom bonded to it), i.e. with a few exceptions, any chemical containing at least one perfluorinated methyl group (-CF3) or one perfluorinated methylene group (-CF2-) is a PFAS.
Leitung
DI Johann Steinwider
- johann.steinwider@ages.at
- efsafocalpoint@ages.at
- +43 50 555 25702
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Spargelfeldstraße 191
1220 Wien
Last updated: 05.05.2026
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