Accounting for Embodied Emissions of Chemicals within the European Carbon Border Adjustment Measure

The Carbon Border Adjustment Mechanism (CBAM) implemented by the European Union (EU) aims to avoid carbon leakage and drive the transition towards net-zero emissions. As the EU considers extending CBAM to the chemical sector by 2030, its effectiveness in this complex industry remains uncertain. Here, we assess the EU CBAM’s effectiveness using a Life-Cycle Assessment of 4,470 global chemical production facilities. We find that the current CBAM framework accounts for 50–60% of production emissions for key products like ethylene and polyethylene. This limited emission coverage risks compromising the policy’s ambition. To address this, CBAM would need to (1) include fossil feedstocks and refinery products, and (2) implement high fallback default values for embodied emissions to incentivize data reporting. Thus, our study underscores the importance of careful supply chain tracking. Furthermore, we recommend engaging chemical industry experts before policy implementation to ensure CBAM fosters an equitable net-zero transition without unintended consequences.