In a revealing new study, researchers have uncovered that the chemicals introduced to protect the ozone layer are inadvertently contributing to the global dispersion of a highly persistent and potentially toxic compound, trifluoroacetic acid (TFA). This ‘forever chemical,’ known for its resistance to degradation, has been spreading across the Earth’s surface in significant quantities, raising alarm among atmospheric scientists and environmentalists alike.
The team of international scientists, spearheaded by experts at Lancaster University, has for the first time quantified the atmospheric deposition of TFA resulting from the degradation of chlorofluorocarbon (CFC) replacement chemicals and certain anesthetics. Their computational modeling estimates that between 2000 and 2022, approximately 335,500 tonnes of TFA have been steadily deposited worldwide, marking a substantial environmental influx of this enduring chemical.
Using sophisticated chemical transport models, the researchers simulated how hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs)—both prominent substitutes for ozone-depleting CFCs—decompose in the atmosphere and generate TFA. These fluorinated gases, commonly referred to as F-gases, have a prolonged atmospheric lifetime that allows them to circulate globally before breaking down, leading to widespread TFA formation even in remote regions like the Arctic.
One particularly concerning facet is that the atmospheric accumulation of TFA from these sources is projected to continue rising, potentially peaking between 2025 and 2100. Despite international regulatory frameworks like the Montreal Protocol and the Kigali Amendment working toward the phase-down of these gases, their legacy emissions and persistent nature pose ongoing environmental challenges.
TFA belongs to the broader family of per- and polyfluorinated alkyl substances (PFAS), a class of chemicals notorious for their stability and environmental persistence, often dubbed ‘forever chemicals’ due to their resistance to natural breakdown processes. The environmental behavior of TFA is increasingly under scrutiny as data shows it now permeates ecosystems worldwide and even traces have been found in human biological samples such as blood and urine.
While some regulatory agencies maintain that current environmental concentrations of TFA remain below thresholds of direct human health concern, there is growing scientific apprehension. The European Chemicals Agency’s classification of TFA as harmful to aquatic life and recent proposals advocating its potential reproductive toxicity underline the urgency to better understand the long-term implications of TFA accumulation.
The study’s lead author, Lucy Hart, emphasized the critical insight that the environmental burden of TFA is dominantly linked to CFC replacements and is not merely a byproduct of isolated industrial uses. This revelation urges environmental policymakers to carefully evaluate the broader systemic consequences when substituting harmful chemicals with alternatives that may possess equally problematic degradation pathways.
To validate their findings, the research team juxtaposed model simulations with empirical data gathered from a variety of environmental samples, including measurements from Arctic ice cores and precipitation. Their atmospheric models incorporated real-time monitoring data to map the spatial distribution of parent gases and track the chemical transformations leading to TFA deposition.
Transport mechanisms modeled in the study indicate that TFA is not simply localized near emission sources but is subject to long-range atmospheric circulation patterns. Rainfall and direct air-to-surface deposition facilitate its widespread dispersion, explaining the conspicuous presence of TFA in even the most remote and pristine environments on the planet.
The identification of hydrofluoroolefins (HFOs), especially HFO-1234yf used extensively in automobile air conditioning systems, as emerging, significant contributors to atmospheric TFA further complicates the outlook. Marketed as climate-friendly refrigerants due to their low global warming potential, these compounds nevertheless degrade into TFA, suggesting a trade-off between near-term climate mitigation and long-term environmental contamination.
Professor Ryan Hossaini of Lancaster University highlighted the urgent need to balance chemical substitution policies against environmental persistence concerns. He noted the paradox that while HFC use is being rolled back, the environmental footprint of their degradation products like TFA will remain an ongoing issue, necessitating comprehensive international monitoring and regulatory research efforts.
Lancaster Environment Centre’s Director, Professor Cris Halsall, underscored the expanding gamut of organofluorine sources contributing to TFA, including refrigerants, solvents, pharmaceuticals, and other PFAS compounds. This diffusion across multiple industrial and commercial sectors complicates the identification and management of TFA pollution.
Complementing these findings, Dr. Stefan Reimann’s Swiss atmospheric research group confirmed consistent trends of increasing TFA concentrations across global measurement sites. The consensus is clear: with the continued use and release of fluorinated gases, TFA accumulation in aquatic and terrestrial ecosystems is likely to intensify, heightening the imperative for sustained surveillance and environmental risk assessment.
Overall, this groundbreaking study published in Geophysical Research Letters delivers a sobering message about the unforeseen environmental consequences tied to efforts aimed at ozone protection. The intersection of atmospheric chemistry, environmental persistence, and chemical policy presents a formidable challenge that demands international collaboration, rigorous monitoring, and innovative regulatory strategies to safeguard both ecosystem and human health against these “forever chemicals.”
Subject of Research: Not applicable
Article Title: Growth in production and environmental deposition of trifluoroacetic acid due to long-lived CFC replacements and anaesthetics
News Publication Date: 4-Feb-2026
Web References: http://dx.doi.org/10.1029/2025GL119216
References: Article in Geophysical Research Letters, DOI:10.1029/2025GL119216
Keywords: Chemical pollution, Environmental sciences, Environmental chemistry, Water pollution, Atmospheric science, Atmospheric chemistry
