Summary

An international study led by Empa shows that ozone layer recovery could be delayed by approximately seven years. The cause is so-called feedstock chemicals such as carbon tetrachloride (CCl₄), which are used as raw materials in industrial processes for modern refrigerants and plastics. Until now, these substances have been exempted from international agreements because their emissions were significantly underestimated. Measurements show that three to four percent of produced feedstock quantities are released into the atmosphere – many times higher than the original assumption of 0.5 percent. The study was published in Nature Communications and is based on global atmospheric measurements from international networks such as AGAGE.

People

Topics

  • Ozone layer and atmospheric protection
  • Feedstock chemicals and industrial emissions
  • Montreal Protocol and international environmental agreements
  • Climate change and greenhouse gases
  • Emission measurement and atmospheric research

Clarus Lead

The delay in ozone regeneration questions the effectiveness of existing international regulations and reveals a regulatory gap in an otherwise successful agreement. While the Montreal Protocol has successfully banned ozone-depleting substances in consumer products, these chemicals continue to escape massively during industrial production – a problem that was systematically underestimated when the Protocol was negotiated in the 1980s. With growing demand for electric vehicles and modern plastics, the use of these feedstock chemicals is actually increasing, not decreasing. This requires political reassessment and possible amendment of the Montreal Protocol to address the dual threat to the ozone layer and climate.

Detailed Summary

The Empa study is based on global atmospheric measurements from the AGAGE network, including the measurement station on the Jungfraujoch. Since ozone-depleting substances remain in the atmosphere for decades, their concentration allows conclusions about current emission rates. Comparison between measured concentrations and officially reported production figures by states reveals a massive discrepancy: while the original assumption was a 0.5 percent leakage rate, actual emissions are at three to four percent – for carbon tetrachloride even above four percent.

The use of feedstock chemicals has increased by approximately 160 percent since 2000. One reason lies in the production chain: initially, these substances were used to manufacture HCFCs (hydrochlorofluorocarbons), which served as replacements for banned CFCs in refrigerants. Since HCFCs later proved to be strong greenhouse gases, they are now being replaced by HFOs (hydrofluoroolefins) – but their production again requires intensive feedstock chemicals. Additionally, application in the polymer industry is growing explosively: fluoropolymers such as Teflon and polyvinylidene fluoride (PVDF) – a key material in lithium-ion batteries for electric cars – are driving demand further.

The consequence is dramatic: instead of 2066, the ozone layer will not fully recover until 2073 under current conditions (uncertainty range: 2066–2077). At the same time, the additional climate-damaging emissions would reach approximately 300 million tons of CO₂ equivalents per year by mid-century – comparable to the annual total emissions of England or France. Stefan Reimann emphasizes that reducing these emissions would have a dual benefit: protection for both the ozone layer and the climate.

Key Statements

  • Seven-year delay: The ozone layer recovers by 2073 instead of 2066 if feedstock emissions are not reduced.
  • Massive underestimation: Actual leakage rates (3–4%) are six to eight times higher than original assumptions (0.5%).
  • Growing use: Feedstock chemical use increased by 160% since 2000, particularly in electric mobility and plastics industry.
  • Dual climate threat: These substances damage both ozone layer and climate; emission reduction would have synergistic benefits.
  • Regulatory gap: Montreal Protocol must be reviewed and amended; decision rests with policymakers and industry.

Critical Questions

  1. Evidence & Measurement Methodology: How reliable are AGAGE measurement stations in capturing global emissions? What uncertainties exist in back-calculating emission rates from concentrations, especially for less frequently measured substances?

  2. Conflicts of Interest & Industry Incentives: What economic incentives do states and companies have to underestimate or conceal their actual feedstock emissions? Are there transparency mechanisms that sanction under-reporting or misreporting?

  3. Causality & Alternatives: Can measured emissions actually be attributed to leakage during production and transport, or do illegal emissions play a role? Do technically available alternatives to feedstock chemicals exist that are economically unprofitable?

  4. Feasibility of Solutions: How realistic is limiting feedstock chemicals when demand for electric vehicles and modern plastics continues to grow? What costs and delays would result from switching to alternative production processes?

  5. Political Implementation: The Montreal Protocol is considered a success model – how likely is an amendment if it affects industry interests in key sectors (batteries, plastics)?

  6. Climate Impact Weighting: Are the 300 million tons of CO₂ equivalents already accounted for in climate targets and emission budgets, or does a hidden gap emerge in the climate balance?

Source Directory

Primary Source: Ozone Protection Under Pressure: Industrial Chemicals Delay Ozone Layer Recovery – news.admin.ch (16.04.2026) https://www.news.admin.ch/de/newnsb/l87UPbkNItaD0pxMcHx61

Supplementary Sources:

  1. Empa Media Release: Industrial Chemicals Delay Ozone Layer Recovery https://www.empa.ch/web/s604/industrie-chemikalien-verzoegern-erholung-der-ozonschicht

  2. Study in Nature Communications (Reimann et al., 2026) – Feedstock Chemicals and Ozone Layer Recovery

Verification Status: ✓ 16.04.2026

This text was created with the assistance of an AI model. Editorial responsibility: clarus.news | Fact-checking: 16.04.2026