The Global Threat from the Irreversible Accumulation of Trifluoroacetic Acid (TFA)

Trifluoroacetic acid (TFA) is a persistent and mobile
substance
that has been increasing in concentration within diverse environmental
media, including rain, soils, human serum, plants, plant-based foods,
and drinking water. Currently, TFA concentrations are orders of magnitude
higher than those of other per- and polyfluoroalkyl substances (PFAS).
This accumulation is due to many PFAS having TFA as a transformation
product, including several fluorinated gases (F-gases), pesticides,
pharmaceuticals, and industrial chemicals, in addition to direct release
of industrially produced TFA. Due to TFA’s extreme persistence
and ongoing emissions, concentrations are increasing irreversibly.
What remains less clear are the thresholds where irreversible effects
on local or global scales occur. There are indications from mammalian
toxicity studies that TFA is toxic to reproduction and that it exhibits
liver toxicity. Ecotoxicity data are scarce, with most data being
for aquatic systems; fewer data are available for terrestrial plants,
where TFA bioaccumulates most readily. Collectively, these trends
imply that TFA meets the criteria of a planetary boundary threat for
novel entities because of increasing planetary-scale exposure, where
potential irreversible disruptive impacts on vital earth system processes
could occur. The rational response to this is to instigate binding
actions to reduce the emissions of TFA and its many precursors.