Study shows: Effective regulation and monitoring are key to combating emissions of a super greenhouse gas

New research has found that factories around the world are not properly destroying one of the most potent greenhouse gases released during the production of fluoropolymers such as Teflon and coolants.

The study examined a known discrepancy between actual and reported emissions of this gas and led to calls for more countries to sign official agreements to limit emissions and for their Teflon factories to be independently audited to ensure compliance.

The study published today in the journal Naturestudied emissions of one of the most potent greenhouse gases, namely hydrofluorocarbons (HFCs) called trifluoromethane, also known as HFC-23. It is mainly produced as a byproduct in the industrial manufacture of certain coolants and Teflon, which is used in products such as non-stick cookware. As part of the Kigali Amendment to the Montreal Protocol, more than 150 countries have committed to significantly reducing their HFC-23 emissions.

Since 2020, all Teflon manufacturers have been required to destroy the powerful greenhouse gas. According to reports from the individual countries that produce these products, this is happening. On paper, global annual emissions of HFC-23 in 2020 were only 2,000 tons, but actual global emissions, which have been proven in numerous studies, paint a different picture. In 2020 alone, around 16,000 tons of the greenhouse gas were released into the atmosphere.

To clarify this discrepancy, researchers from the University of Bristol in the UK, Empa in Switzerland and the Netherlands Organisation for Applied Scientific Research compared the HFC-23 levels reported by individual countries with the actual emission levels of a Teflon factory in the Netherlands.

In order to record the emissions as comprehensively and accurately as possible, a new technique was used. A tracer was released right next to the factory: a non-toxic gas that does not occur in the atmosphere and decomposes within a few weeks. At a distance of around 25 kilometers, they then measured the concentrations of HFC-23 and other byproducts of Teflon production – as well as the concentration of the tracer.

Lead author Dr Dominique Rust, research associate at the University of Bristol, said: “Because we knew exactly how much tracer we had released and how much of it reached the measuring point, we were able to calculate the emissions of HFC-23 and other gases.”

The results showed that the measures to reduce HFC-23 levels are largely effective, even though the estimated emissions are higher than those reported by the plant.

The results showed that if all factories worldwide controlled emissions in the same way as the one studied, HFC-23 emissions could be reduced by around 85%. This reduction corresponds to almost a fifth (17%) of the carbon dioxide emissions of all aviation.

Dr Rust, who contributed to the study as part of her doctoral thesis at Empa, the Swiss Federal Laboratories for Materials Science and Technology, added: “The collaboration with the Teflon manufacturer and the Dutch authorities was key to understanding the true picture.”

Co-author Dr. Martin Vollmer, a researcher at Empa, said: “We suspect that the higher actual values ​​in the global atmosphere are due to some countries underreporting their emissions, which leads to this discrepancy. One explanation for this is that emission reduction technologies are not being implemented as effectively worldwide as in the factory we studied.”

The researchers are calling for an independent audit of the factories. This independent verification of greenhouse gas emissions from the production of fluoropolymers and coolants would help fill gaps in the understanding of the sources of emissions and verify that countries are fully complying with the various international climate and environmental agreements.

Co-author Dr Kieran Stanley, senior research fellow at the University of Bristol, said: “Studies like this can help us independently verify reported emissions reductions from fluorochemical plants and ensure that countries are meeting their commitments under the Kigali Amendment to the Montreal Protocol.”

“These results are therefore really encouraging and show that emission reductions from fluorochemical plants that produce fluoropolymers such as Teflon can significantly reduce emissions of a highly potent greenhouse gas.”

The researchers are now planning another study in South Korea for October. In the capital Seoul, they want to use the tracer method to determine the emissions of other halogenated substances.