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

This study emphasizes the alarming environmental and health implications of trifluoroacetic acid (TFA), a type of perfluoroalkyl acid (PFAA), which is by far the most abundant PFAS compound in the environment. TFA, which was initially associated with the degradation of fluorinated refrigerants introduced as alternatives for ozone-depleting CFCs, has become increasingly alarming due to its widespread presence in drinking water and human blood. While earlier assessments suggested it was less harmful than other PFAS, this study demonstrates that its persistent environmental accumulation and potential to disrupt human health and Earth systems make it a planetary boundary threat.

Increasing Planetary Exposure

Recent studies show TFA contamination is widespread and increasing, with median concentrations ranging from 0.21µg/l to 0.70 µg/l in precipitation and from 0.08 µg/l to 1.5 µg/l in drinking water. These median concentrations are similar to or even higher than the proposed limits of total PFAS in drinking water in the EU draft Drinking Water Directive (threshold of 0.5µg/l total PFAS). The current study also highlights TFA’s rapid accumulation in crops and other plants, which leads to higher human exposure through plant-based food and beverages. Furthermore, TFA levels in human blood have risen significantly, comparable to long-chain PFAS, despite its supposed non-bioaccumulative nature.

Persistence and Sources

TFA is highly persistent and mobile in the environment, accumulating in water bodies, soil, and plants. Major sources include fluorinated gases used as refrigerants, which transform into TFA, as well as industrial production and processes, agrochemicals, and pharmaceuticals. TFA emissions in Europe alone were estimated at 6,900 tons annually by 2020, with projections reaching 47,650 tons by 2050. This accumulation, driven by anthropogenic emissions, leads to rising concentrations in ecosystems, agriculture, and human populations, with currently no effective or affordable removal methods.

Disruptive Effects on Health and Earth Systems

The health and environmental impact of TFA is still unknown. While some studies suggest mild liver toxicity in rats after high doses of TFA, there is a lack of long-term studies to assess chronic exposure risks. Long-term studies are however crucial given TFA’s persistence and accumulation. TFA’s toxicity to aquatic organisms, plants, and soils raises concerns, as it enters food webs, potentially impacting crops and livestock. Chronic exposure to TFA may have far-reaching effects on ecosystems, health, and food security, requiring urgent research and action.

Recommendations

Given its growing environmental and health risks, it is crucial to limit TFA production and emissions. This can be achieved by phasing out its precursors, such as HFOs (hydrofluoroolefins) and certain pesticides, as well as implementing policies to reduce industrial emissions. Immediate global action is deemed needed to prevent irreversible health and environmental impacts. As research progresses, new regulatory limits for TFA are expected, underscoring the importance of transitioning away from its use to safeguard future generations.

The study “The Global Threat from the Irreversible Accumulation of Trifluoroacetic Acid (TFA)” by Arp et al. was published in Environmental Science & Technology.