Forever’s chemical TFA tripled with ozone-preserving refrigerants

Trifluoroacetic acid (TFA), a potentially toxic “forever chemical,” has more than tripled in the global environment in two decades thanks to refrigerants that help plug the hole in the ozone layer.

The amount of TFAs falling from the atmosphere through wind and rain has increased from 6,800 tons per year in 2000 to 21,800 tons in 2022. Although this is below known safe thresholds, the effects of TFAs on human health have not been studied in detail, and their accumulation in the environment is expected to accelerate.

TFA caused eye deformity in most fetal rabbits exposed to it in one trial. The European Union has classified it as harmful to aquatic life and is considering whether to consider it toxic to human reproduction.

“It’s shocking that we’re releasing a large amount of a chemical into the environment, that we have a very poor understanding of its effects, and it’s basically irreversible,” he says. Lucy Hart at Lancaster University in Great Britain, who led the new research.

Humans and animals will be exposed to TFA in soil and surface water until it flows into the sea and becomes trapped in ocean sediments over decades or centuries.

Chlorofluorocarbons (CFCs) were once found in refrigerators, aerosol sprays, fire extinguishers and other items. But they were banned in 1989 after they were found to create a hole in the Earth’s protective ozone layer. They have been largely replaced by hydrofluorocarbons (HFCs), which react with hydroxyl radicals in the atmosphere to form compounds including TFA.

While HFCs are now being phased out, they are often replaced by hydrofluoroolefins (HFOs), which break down into TFAs at a much higher rate. HFO-1234yf which is now found in air conditioners in hundreds of millions of cars, it produces 10x more TFA than the HFC it is gradually replacing. Pesticides, pharmaceuticals and industrial chemicals are also a source of TFA.

Cores from ice caps in northern Canada and Svalbard have revealed that TFA concentrations have been increasing there since the 1970s. Based on long-term atmospheric measurements of nine CFC surrogate gases, Hart and her colleagues modeled the rate at which TFA was produced and deposited worldwide, revealing a 3.5-fold global increase.

This rate could double by 2050, based on HFCs alone, which can last several decades in the atmosphere. Other research found that HFO-1234yf could increase TFA production more than 20-fold by 2050.

While the world cannot go back to CFCs and should continue to move away from HFCs, which have a significant effect on global warming, substitutes for these chemicals need further scrutiny, he says Lucy Carpenter at the University of York in Great Britain.

Ammonia already cools many food warehouses and industrial processes, and could also be used in home refrigerators and air conditioners. Another natural refrigerant is carbon dioxide.

“We need to seriously look at whether there are better alternatives to HFO-1234yf,” says Carpenter. “TFA has increased and will continue to increase… It’s been found in all kinds of food products where it’s never been. It’s everywhere.”

See you in 2020 studies found high concentrations of TFA in the blood of 90 percent of people in China, a hotspot for the chemical due to industrial pollution and warm, humid weather in many places.

The EU, which is preparing proposals to ban the perennial chemicals, has predicted that TFA concentrations in fresh water will eventually reach toxic levels. But he came under fire recruitment a consulting company that also lobbied for chemical manufacturers and disputed the expected increase in TFA.

The new findings call for the study of both HFOs and possible replacements, so countries can break the cycle of accepting chemicals with unintended consequences, Hart says. Unlike HFCs, HFOs break down within days, giving us more control. “If we stop issuing them, you’re going to stop making TFA very quickly,” he says.

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