TFA in drinking water: Czech reference centre recommends a guideline value of 10 µg/l and a maximum limit of 20 µg/l
On 7 September 2026 the National Reference Centre for drinking water at the Czech National Institute of Public Health (SZÚ) published an updated recommendation on trifluoroacetic acid (TFA) in drinking water. Following EFSA’s assessment of July 2026, it lowered the proposed maximum limit from 25 to 20 µg/l.
- TFA has no limit in the Czech drinking water decree (Decree No. 252/2004 Coll.), so the Public Health Protection Act applies: where a substance not on the list is suspected, the water supplier determines its concentration and reports the result to the public health authority, which sets a limit. The parameter “PFAS total” (0.50 µg/l in Directive 2020/2184) was not included in the Czech decree because there is no fully reliable method for determining it.
- Once TFA is reported, the centre recommends setting a guideline value of 10 µg/l and, where a result above 10 µg/l is confirmed, a maximum limit of 20 µg/l; as a target value it gives 2.2 µg/l, derived in 2023 by the Dutch RIVM. The first results of monitoring surface and groundwater in Czechia showed averages from tenths of a µg/l to a few µg/l, with maxima of a few µg/l.
- The basis was a tolerable daily intake of 0.018 mg/kg bw set in 2026 by the German Environment Agency UBA (which calculated 63, rounded to 60 µg/l, for adults); the Czech centre calculated for infants, allocating 20% of that intake to water, and obtained 25 µg/l. After EFSA’s new ADI of 0.014 mg/kg bw per day, the safe value for infants moved closer to 20 µg/l. By March 2026 nine EU/EFTA countries had set or recommended a TFA limit, ranging from 2.2 to 60 µg/l.
- For results above 5 µg/l the centre recommends testing TFA at the frequency of a full analysis, and for results between the limit of quantification and 5 µg/l once every three years. Common treatment technologies do not significantly change the TFA content of treated water; the recommendation was issued in agreement with the Czech Ministry of Health.