Researchers from Lancaster University have conducted the first count of the amount of this pollutant that has accumulated on the planet. The analysis revealed that from 2000 to 2022, approximately 335,500 tons of trifluoroacetic acid (TFA) entered the atmosphere as a result of replacing HFCs and using anesthetic gases.
An article published in the journal Geophysical Research Letters warns that the pollution problem has not yet peaked. Many substances that replace HFCs remain in the atmosphere for decades, contributing to the continued influx of TFA into the environment. Projections indicate that annual TFA production could reach its peak between 2025 and 2100.
TFA is formed from the breakdown of hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs), which are widely used in refrigeration systems and as inhalation anesthetics. Despite a gradual reduction in their use in accordance with international agreements such as the Montreal Protocol and the Kigali Amendment, the concentration of these substances in the atmosphere continues to rise.
Trifluoroacetic acid belongs to the class of per- and polyfluoroalkyl substances (PFAS), known as "forever chemicals" due to their resistance to natural degradation and long-term existence in ecosystems.
The European Chemicals Agency considers TFA to be hazardous to aquatic flora and fauna. This chemical has also been found in human blood and urine, and the Federal Institute for Occupational Safety and Health in Germany recently proposed classifying TFA as potentially toxic to the human reproductive system.
"Our research indicates that HFC substitutes have likely become the primary source of TFA in the atmosphere," commented lead author Lucy Hart. "This underscores the need to consider broader risks when replacing hazardous chemicals."
The results show that nearly all TFA found in the Arctic originates from chemical substitutes for HFCs, despite the remoteness of this region from major emission sources. "Research is recording rising levels of TFA in Arctic ice cores, and our data convincingly confirms for the first time that almost all of these deposits can be explained by these gases," Hart added.
Outside polar regions, modeling confirms the growing role of HFO-1234yf, which is often used in automotive air conditioning systems, as an important and likely increasing source of atmospheric TFA.
"The observed levels of TFA from fluorinated gases are impressive. Although the use of HFCs is gradually decreasing, this source of TFA will remain relevant for many years to come. There is an urgent need to investigate other sources of TFA and assess their environmental impact," emphasized Professor Ryan Hosseini.
